DieMark Inking Products

Cause a): The time interval between inking the wafer and heat curing is too long (DieMark 699x-series inks only).
Solution a): Xandex recommends curing inked wafers of 699x inks within 2 hours after inking. Under some conditions of high air flow or high temperature, even two hours between inking and curing may be too long.

Cause b): Ink has been placed over the interface between two types of wafer surfaces that have different coefficients of thermal expansion. When the wafer is heated during curing, the two surfaces expand differently and cause cracks to develop.
Solution b): Place the ink dots in a different area of the device that has a uniform surface.

Cause c): Ink was partially cured at low temperature (somewhere between ambient and 50 C) prior to oven curing. Under certain conditions, only the edges of the dots will cure at the low temperature. When the partially cured dots are placed in the oven, the uncured middle portion of the dot contracts as it cures and causes cracking.
Solution c): Reduce (or increase) the amount of time that the wafers are exposed to the lower temperature. If using a hot chuck, change the chuck temperature or do not use the hot chuck. DieMark 699x inks are not recommended for use with a hot chuck.

Cause a): Ink is being placed onto a surface with an unusually low surface energy.
Solution a): Take steps to increase the surface energy prior to inking. Gas plasma cleaning/surface activation and/or solvent cleaning may lead to improved adhesion. Increasing the ink cure temperature to around 150o C will also improve the adhesion in some cases.

Cause b): Wafer surface contamination.
Solution b): Any type of contaminant that weakly adheres to the surface of the substrate or lowers the surface energy will cause the ink to adhere poorly and flake off.
Related Information: See DieMark Ink Remover data sheet

Cause c): Ink dots have cracked during curing, compromising the adhesion quality.
Solution c): See Ink Dots Crack After Curing section for possible causes and solutions.

Cause d): Batch specific ink problem.
Solution d): Return cartridges to Xandex for testing and possible warranty replacement.

Cause a): Ink is being placed onto a surface with an unusually high surface energy. Depending on the type of material, spreading behavior and size of the ink droplet may vary significantly.
Solution a): Switch to a different cartridge size and/or a higher viscosity ink. If using a DM-2, reduce the Dot Size Setting to compensate for the larger dots.

Cause b): The ambient temperature is higher than the recommended maximum temperature listed on the cartridge packaging (or higher than your normal operating temperature). Ink viscosity is lower at higher temperatures. Ink storage temperature and inking temperatures should be within the recommended range.
Solution b): Reduce the cartridge storage and inking temperature to the recommended range: Storage = 50-77 F (10-25 C). Inking = 67-77 F (19.5-25 C).

Cause c):Ink has dropped below the specified viscosity range. This should not occur under normal conditions, as long as the cartridges are not past their expiration date and have been stored and used properly. Some inks, however, will experience viscosity changes if exposed to temperature extremes during shipping.
Solution c): Request RMA to return sample cartridges to Xandex for testing and possible warranty replacement.

Cause a): Ink is being placed onto a surface with a non-uniform topography. A rough or patterned surface will lead to irregularly shaped dots as the ink flows unevenly across peaks and valleys on the surface.
Solution a): Place the ink dots in a different, more uniform area of the die.

Cause b): The Z-height is set too low. A consistent pattern of non-uniform dots often indicates improper Z-height adjustment.
Solution b): Raise the z-height to a setting that yields round dots without any skipping.

Related Information: See Inker Set-up Procedure in the inker Operation Manual for detailed instructions.

Cause c): The needle tip has been damaged.
Solution c): Replace the damaged cartridge with a fresh one.

Cause d): Ink is being placed onto a surface with a non-uniform surface chemistry. Variations in the surface chemistry lead to variations in the surface energy. The ink flows more readily in areas with higher surface energy.
Solution d): Take steps to improve the surface uniformity. If the cause of the non-uniformity is determined to be organic contaminants, a cold gas plasma or solvent bath cleaning process may be helpful.

Cause e): Cartridge filament length, filament diameter, or needle diameter is out of specification (filament systems only).
Solution e): Replace with a fresh cartridge. Return the suspect cartridge to Xandex for test confirmation and possible warranty replacement.

Cause a): Dot size setting on the pneumatic controller is set too low (pneumatic systems only).
Solution a): Increase the dot size setting.

Cause b): Air pressure to pneumatic controller is too low (pneumatic systems only).
Solution b): Set the air pressure to the pneumatic controller at 70 ±10 psi on all controllers except Motorized Z controller which should be set to 80 ± 5 psi.

Cause c): The cartridge size is too small.
Solution c): Change to a larger cartridge size.

Cause d): Dot size potentiometer is defective (pneumatic systems only). Run Diagnostics Test B described in Controller Diagnostics section of the Operations manual. If test results are not within specified parameters, contact Xandex Customer Service.
Solution d): Replace dot size potentiometer.

Cause e): Ink is being placed onto a surface with an unusually low surface energy. Depending on the type of material, spreading behavior and size of the ink droplet may vary significantly.
Solution e): Switch to a different cartridge size and/or a lower viscosity ink. If using a DM-2 cartridge, increase the Dot Size Setting on the pneumatic controller to compensate for the smaller dots.

Cause f): The ambient temperature in the inking area is lower than normal. Ink viscosity is higher at lower temperatures. Higher viscosity leads to smaller ink dots. For best performance, inking temperatures should be between 67 and 77 F (19.5-25 C).
Solution f): Increase the ambient inking temperature to the recommended range. If storing the cartridges at less than 67 F (19.5 C), allow time for the cartridges to equilibrate to room temperature prior to inking.

Cause g): Ink has risen above the specified viscosity range. This should not occur under normal conditions, as long as the cartridges are not past their expiration date and have been stored and used properly. Some inks, however, will experience viscosity changes if exposed to temperature extremes during shipping.
Solution g): Return sample cartridges to Xandex for testing and possible warranty replacement.

Cause a): Dot size setting on the pneumatic controller is too high (pneumatic systems only).
Solution a): Decrease dot size setting.

Cause b): Air pressure to pneumatic controller is too high (pneumatic systems only).
Solution b): Set the air pressure to the pneumatic controller at 70 ±10 psi on all controllers except Motorized Z controller which should be set to 80 ± 5 psi.

Cause c): The cartridge size is too large.
Solution c): Change to a smaller cartridge size.

Cause d): Dot size potentiometer is defective (pneumatic systems only). Run Diagnostics Test B described in Controller Diagnostics section of the Operations manual. If test results are not within specified parameters, contact Xandex Customer Service.
Solution d): Replace dot size potentiometer.

Cause e): Ink is being placed onto a surface with an unusually high surface energy. Depending on the type of material, spreading behavior and size of the ink droplet may vary significantly.
Solution e): Switch to a different cartridge size and/or a higher viscosity ink. If using a DM-2 cartridge, reduce the Dot Size Setting to compensate for the larger dots.

Cause f): The ambient temperature is higher than the recommended maximum temperature listed on the cartridge packaging (or higher than your normal operating temperature). Ink viscosity is lower at higher temperatures. Lower viscosity leads to larger ink dots. Ink storage temperature and inking temperatures should be within the recommended range.
Solution f): Reduce the cartridge storage and inking temperature to the recommended range: Storage = 50-77 F (10-25 C). Inking = 67-77 F (19.5-25 C).

Cause g): Ink has dropped below the specified viscosity range. This should not occur under normal conditions, as long as the cartridges are not past their expiration date and have been stored and used properly. Some inks, however, will experience viscosity changes if exposed to temperature extremes during shipping.
Solution g): Return sample cartridges to Xandex for testing and possible warranty replacement.

Cause a): The inker Z-height is set too high. A consistent pattern of skipping dots often indicates improper Z-height adjustment.
Solution a): Lower the inker Z-height to a setting that yields round dots without any skipping.

Related Information: See Inker Set-up Procedure in the inker Operations Manual for detailed instructions.

Cause b): Cartridge was not primed correctly and needs to be re-primed (filament inkers only).
Solution b): Re-prime cartridge per instructions on cartridge packaging and run a thousand dots on a test wafer.

Cause c): Cartridge needle tip is damaged.
Solution c): Replace the damaged cartridge with a new one.

Cause d): The cartridge needle is clogged with a debris particle (pneumatic inkers only).
Solution d): Replace the suspect cartridge with a new one. Return the suspect cartridge to Xandex for test confirmation and possible warranty replacement.

Cause e): Air bubble (pneumatic inkers only). Small air bubbles are sometimes present during the first 1,000 dots after initial cartridge priming.
Solution e):Run 1,000 dots onto a test wafer. This should eliminate any bubbles that may have been present inside of the cartridge.

Cause f): Inking surface is not planar. This can be caused by variations in wafer thickness or if the prober head plate or chuck is tilted slightly relative to perfect horizontal. If the dot skipping only occurs on one side of the wafer, it is most likely due to planarity problems.
Solution f): Check the planarity of the prober head plate and chuck. Make planarity adjustments per the prober manufacturers recommended procedure.

Cause g): Prober Z stage equipment problem. The stage Z drive assembly photocells may be defective or contaminated with dust (if prober is so equipped). Z stage malfunction can cause the amount of stage travel in the z direction to be non-uniform, resulting in skipped dots.
Solution g): Refer to prober manufacturers recommended verification procedure to insure correct operation of the prober Z stage drive and clean, adjust or replace components as necessary.

Cause h): Inker equipment problem (pneumatic inkers only). Pneumatic inker shuttle is clogged with dried ink or other debris, or has been used outside the recommended shuttle preventive maintenance period causing inconsistent shuttle motion.
Solution h): Perform recommended preventive maintenance on the shuttle using the appropriate shuttle maintenance kit (available from Xandex). Replacement of the shuttle may be required if shuttle has been damaged due to a lack of regular preventive maintenance.

Cause i): Inker equipment problem (pneumatic inkers only). Pneumatic controller has not received regular preventive maintenance, resulting in inconsistent shuttle and/or cartridge actuator valve performance.
Solution i): Perform recommended preventive maintenance on the controller using the appropriate controller maintenance kit (available from Xandex).

Cause j): (DM-1 Only) Air bubble is entrapped in the cartridge needle or needle channel. Air bubbles can be forced into the needle if the cartridge is re-closed at any time after the initial opening of the cartrtidge. The cartridge should be left in the open, inking position at all times.
Solution j): Leave the cartridge open at all times after initial opening. Do not re-close the cartridge.

Cause a): Cartridge was not primed correctly and needs to be re-primed (filament inkers only).
Solution a): Re-prime cartridge per instructions on cartridge packaging and run a thousand dots on a test wafer.

Cause b): Cartridge needle tip is damaged.
Solution b): Replace the damaged cartridge with a new one.

Cause c): The cartridge needle is partially clogged with a debris particle (pneumatic inkers only).
Solution c): Replace the defective cartridge with a new one. Return the suspect cartridge to Xandex for testing and possible warranty replacement.

Cause d): Air bubble (pneumatic inkers only). Small air bubbles are sometimes present during the first 1,000 dots after initial priming of the cartridge.
Solution d): Run 1,000 dots onto a test wafer. This should eliminate any bubbles that may have been present inside of the cartridge.

Cause e): Ink has accumulated on the outside, metal portion of the needle (ink “balling”). This may occur due to excessive priming or if the inker is fired multiple times without depositing any ink (e.g. if the Z-height is too high during the initial adjustment). If using a pneumatic system, it may also occur due to a cartridge defect that causes leakage between the Teflon and metal portions of the needle.
Solution e): Carefully remove all the excess ink from the needle using a lint-free tissue or swab before continuing with inking operation. If ink continues to accumulate on the outside of the needle multiple times, the cartridge may be defective and should be returned to Xandex for testing and possible warranty replacement.

Cause f): Prober Z stage equipment problem. The stage Z drive assembly photocells may be defective or contaminated with dust (if prober is so equipped). Z stage malfunction can cause the amount of stage travel in the z direction to be non-uniform, resulting in skipped dots.
Solution f): Refer to prober manufacturers recommended verification procedure to insure correct operation of the prober Z stage drive and clean, adjust or replace components as necessary.

Cause g): Inker equipment problem (pneumatic inkers only). Pneumatic inker shuttle is clogged with dried ink or other debris, or has been used outside the recommended shuttle preventive maintenance period causing inconsistent shuttle motion.
Solution g): Perform recommended preventive maintenance on the shuttle using the appropriate shuttle maintenance kit (available from Xandex). Replacement of the shuttle may be required if shuttle has been damaged due to a lack of regular preventive maintenance.

Cause h): Inker equipment problem (pneumatic inkers only). Pneumatic controller has not received regular preventive maintenance, resulting in inconsistent shuttle and/or cartridge actuator valve performance.
Solution h): Perform recommended preventive maintenance on the controller using the appropriate controller maintenance kit (available from Xandex).

Cause i): Ink is being placed onto a surface that varies in surface energy. This can be due to variations in surface chemistry or topography.
Solution i): Take steps to make the surface more uniform. Gas plasma cleaning/surface activation and/or solvent cleaning may be helpful in some cases.

Cause j): Cartridge filament length, filament diameter, or needle diameter is out of specification (filament systems only).
Solution j): Replace with a fresh cartridge. Return the suspect cartridge to Xandex for test confirmation and possible warranty replacement.

Cause k): 6993 ink used in hot chuck applications only. Condensation of ink solvent vapors on the needle tip can lead to solvent build-up and periodic deposition on the wafer under certain conditions. This will only occur in low yield off-line applications where large numbers of ink dots are placed rapidly with a very close spacing.
Solution k): Xandex does not recommend the use of 69xx series inks with a hot chuck.

1. Reduce the inking speed and/or change the chuck temperature.
2. Wipe off the needle tip with a lint free cloth if any significant of accumulation of ink solvent is observed.

Cause L): (DM-1 Only) Air bubble is entrapped in the cartridge needle or needle channel. Air bubbles can be forced into the needle if the cartridge is re-closed at any time after the initial opening of the cartrtidge. The cartridge should be left in the open, inking position at all times.
Solution L): Leave the cartridge open at all times after initial opening. Do not re-close the cartridge.

Cause M): Ink has dropped below the specified viscosity range. This should not occur under normal conditions, as long as the cartridges are not past their expiration date and have been stored and used properly. Some inks, however, will experience viscosity changes if exposed to temperature extremes during shipping.
Solution M): Request RMA to return sample cartridges to Xandex for testing and possible warranty replacement.

Cause a): Ink is being placed onto a surface with an unusually low surface energy.
Solution a): Take steps to increase the surface energy prior to inking. Gas plasma cleaning/surface activation and/or solvent cleaning may lead to improved adhesion. Increasing the ink cure temperature to around 150o C will also improve the adhesion in some cases.

Cause b): Wafer surface contamination.
Solution b): Any type of contaminant that weakly adheres to the surface of the substrate or lowers the surface energy will cause the ink to adhere poorly.

Cause c): Ink dots have cracked during curing, compromising the adhesion quality.
Solution c): See Ink Dots Crack After Curing section for possible causes and solutions.

Cause d): Batch specific ink problem.
Solution d): Return sample cartridges to Xandex for testing and possible warranty replacement.

Cause a): Ink is spreading more than usual, causing a decrease in the ink film thickness. Ink spreading behavior is influenced by ink temperature, ink viscosity, and surface energy characteristics of the substrate.
Solution a): See Ink Appears Thin or Runny section for more detailed information regarding ink spreading behavior.

Cause b): Ink dye level is too low. This is unlikely since the dye level of each ink batch is tested prior to loading into cartridges.
Solution b): Return sample cartridges to Xandex for testing and possible warranty replacement.

Cause a): The inker Z-height is set too high.
Solution a): Lower the inker Z-height to a setting that yields round dots without any skipping.

Related Information: See Inker Set-up Procedure in the Operations Manual for detailed instructions.

Cause a): Controller-shuttle air tubing is not plugged into the pneumatic controller.
Solution a): Plug air tubing into the controller.

Cause b): Controller-shuttle air tubing is kinked, clogged, or pinched closed.
Solution b): Remove any constrictions or clogging in the air tubing.

Cause c): No compressed air to the system.
Solution c): Establish compressed air flow to the system at 70 (+/-10) psi on all controllers except the Motorized Z controller which should be set to 80 ± 5 psi.

Cause a): Air hose to the top of cartridge is not connected.
Solution a): Connect air hose.

Cause b): Air hose to the top of cartridge is kinked, clogged or pinched.
Solution b): Remove any constrictions in the tubing and clean as required.

Cause c): Cartridge has not been primed.
Solution c): Prime the artridge according to the directions on the cartridge packaging.

Cause d): Defective cartridge. Priming tool failed to puncture the plastic membrane in the cartridge body.
Solution d): Replace with a fresh cartridge. Return the suspect cartridge to Xandex for test confirmation and possible warranty replacement.

Cause e) The Teflon tip of cartridge needle has been damaged.
Solution e): Replace with a fresh cartridge.

Cause f): The cartridge needle is clogged with a debris particle.
Solution f): Replace with a fresh cartridge. Return the suspect cartridge to Xandex for test confirmation and possible warranty replacement.

Cause g): The rubber washer on the cartridge air hose connector is not installed.
Solution g): Install the washer.

Cause a): The air tubes from the controller to the inker are not connected properly.
Solution a): Connect RED AIR HOSE to the ink cartridge and BLUE AIR HOSE to the connection on the shuttle mechanism.

Note: The causes of backflow are complex. Backflow problems are often caused by a combination of more than one of the factors listed below. For an instructive video of correct filament cartridge operation and use, click HERE (WMV 9Mb) Backflow Research Statement (PDF 21Kb)

Cause a): Overly aggressive priming of the ink cartridge
Solution a): Reduce the amount of time spent priming the cartridge (as described in step #2 on the cartridge packaging). The purpose of cartridge priming is to force the ink into the needle and eliminate any entrapped air bubbles. No more than 60 seconds should be required for this operation.

Cause b): The cartridge is being primed improperly, or opened and closed frequently. Any operation that repeatedly moves the cartridge main guide shaft from the open, inking position to the closed position may lead to increased backflow.
Solution b):

1. Prime cartridge correctly - always perform step 2 of the priming operation with the notches on the cartridge body and main guide 180 degrees apart from each other. Never prime with the notches aligned.
2. Avoid Frequent opening and closing - leave the cartridges open when not in use, or only close the cartridges if the inker down time will be very long (>12 hours).

Cause c): Plunger stop assembly is not being used (DM-1 5 mil cartridge applications). The 5 mil application requires limited plunger travel to inhibit backflow and provide consistent performance. See Plunger Stop listing in the electric inking information section here.
Solution c): Purchase and install the plunger stop assembly and make sure that it is set at 1.25 turns from maximum to limit plunger travel.

Cause d): Ink temperature is too low.
Solution d): Increase the ambient temperature in the inking area. If backflow is a problem, Xandex recommends that the ambient temperature be no less than 70 F (21 C) in the inking area. If storing cartridges at below 70 F, allow time for the cartridges to equilibrate to ambient temperature prior to inking.

Cause e): The inking speed is too fast.
Solution e): Reduce the inking speed. If possible, the inking speed should be less than 6 dots/second if backflow is a problem.

Cause f): Ink cartridge has been open and in use for longer than the Xandex recommended time interval for consistent flow.
Solution f): Do not use the cartridges for longer than the recommended time interval.

Related Information: Refer to the Ink section of the Cartridge Operations Manual (PDF) for cartridge priming instructions and recommended “open” time for consistent ink flow in regard to the specific ink type that you are using.

Cause a): The time interval between inking the wafer and heat curing is too long (DieMark 699x-series inks only).
Solution a): Xandex recommends curing inked wafers of 699x inks within 2 hours after inking. Under some conditions of high air flow or high temperature, even two hours between inking and curing may be too long.

Cause b): Ink was partially cured at low temperature (somewhere between ambient and 50 C) prior to oven curing at a higher temperature. Under certain conditions, only the edges of the dots will cure at the low temperature. When the partially cured dots are placed in the oven, the uncured middle portion of the dot contracts as it cures and causes a “halo”.
Solution b): Reduce (or increase) the amount of time that the wafers are exposed to the lower temperature. If using a hot chuck, change the chuck temperature or do not use the hot chuck. DieMark 699x inks are not recommended for use with a hot chuck.

Cause c): The surface of the substrate onto which the dots are being placed is porous/rough (on a microscopic scale). In some cases a capillary or chromatographic effect can pull solvents out of the main ink droplet, creating a “halo”.
Solution c): If possible, take steps to make the surface more uniform.

Cause a): Ink dots were only partially cured before they were subjected to additional processing steps. The middle, uncured portion of the dots were removed leaving only the cured outer portion.
Solution a): Increase the ink cure time and/or temperature.

Cause b): The inker assembly Z-height is set too low, allowing the filament or needle tip to make contact with the wafer, deforming the ink dot as it is placed.
Solution b): Raise the inker assembly Z height to the proper setting to produce round uniform dots. See the Product Manuals Section of the website to locate the product manual for your inker assembly for setup instructions.

Cause a): Ink cartridge main guide is not locked into place after priming (filament systems only).
Solution a): If the main guide is not locked into place after priming, ink may leak around the top o-ring. Review the priming instructions on the cartridge packaging and lock the main guide into place. If leakage is excessive, it may be more convenient to discard the cartridge and install a new one.

Cause b): The rubber washer on the cartridge air hose connector is not installed (Pneumatic systems only).
Solution b): Install the washer.

Cause c): Ink cartridge is defective or was damaged by improper handling during the priming process.
Solution c): Replace with a fresh cartridge. Return the suspect cartridge to Xandex for test confirmation and possible warranty replacement.

Cause d): (Pneumatic systems only) Pressure difference between internal cartridge pressure and external ambient pressure. Ink flows out of the needle tip immediately after breaking the cartridge seal.
Solution d): Break the cartridge seal and allow 15 minutes for the pressure inside the cartridge to equilibrate with external pressure before mounting the cartridge on the inker. Removal of the cartridge cap may speed this process. Remove excess ink from the needle tip before mounting the cartridge on the inker.

Cause a): Due to unavoidable manufacturing tolerances, there may be a slight variation in dot size after changing a cartridge.
Solution a): After priming and installing the new cartridge, place test dots on a scrap wafer and adjust inker Z-height until desired dot size is achieved. Usually, Z adjustment of 0.001" - 0.002" in either direction is sufficient to accommodate for tolerance differences between cartridges.

Related Information: Also see Inconsistent Dot Size in this section.

Cause a): Dot size setting has been changed on the pneumatic controller (pneumatic systems only).
Solution a): Adjust the dot size setting to your normal set point.

Cause b): Air pressure to pneumatic controller is too low (pneumatic systems only).
Solution b): Set the air pressure to the pneumatic controller at 70 ±10 psi on all controllers except Motorized Z controller which should be set to 80 ± 5 psi.

Cause c): Dot size potentiometer is defective (pneumatic systems only). Run Diagnostics Test B described in Controller Diagnostics section of the Operations manual. If test results are not within specified parameters, contact Xandex Customer Service.
Solution c): Replace dot size potentiometer.

Cause d): Ink is being placed onto a surface with an unusually low surface energy. Depending on the type of material, spreading behavior and size of the ink droplet may vary significantly.
Solution d): Switch to a different cartridge size and/or a lower viscosity ink. If using a DM-2 cartridge, increase the Dot Size Setting to compensate for the smaller dots.

Cause e): The ambient temperature in the inking area is lower than normal. Ink viscosity (thickness) is higher at lower temperatures. Higher viscosity leads to smaller ink dots. For best performance, inking temperatures should be between 67 F and 77 F (19.5-25 C).
Solution e): Increase the ambient inking temperature to the recommended range. If storing the cartridges at less than 67 F (19.5 C), allow time for the cartridges to equilibrate to room temperature prior to inking.

Cause f): Ink has risen above the specified viscosity range. This should not occur under normal conditions, as long as the cartridges are not past their expiration date. Some inks, however, will experience viscosity changes if exposed to temperature extremes during shipping.
Solution f): Return sample cartridges to Xandex for test confirmation and possible warranty replacement.

Cause a): Ink cartridge was over-primed. If using a DM-2 (pneumatic) cartridge, do not prime the cartridge any longer than is necessary for a small bead of ink to appear at the needle tip. If using a DM-1 (filament) cartridge, do not plunge the main guide up and down (Step 2 of the instructions on the package) for longer than one minute (60 seconds).
Solution a): Carefully remove all the excess ink from the needle using a lint-free tissue or swab before continuing with inking operation.

Related Information: Refer to the appropriate Cartridge Preparation and Installation sections of the Cartridge Operations Manual (PDF) for detailed priming instructions.

Cause b): Inker has been fired multiple times without depositing ink. This can occur if the z-height is positioned too high during the initial installation and adjustment of a new cartridge. It can also occur in some cases if the edge sensor is not adjusted properly and causes the inker to fire when the cartridge is not positioned over the wafer.
Solution b): Carefully remove all the excess ink from the needle using a lint-free tissue or swab before continuing with inking operation.

Cause c): Ink cartridge is defective (pneumatic systems only). If the ink balling occurs multiple times and the causes listed above have been ruled out, the cartridge is probably defective. If the cartridge is defective, leakage is occurring between the Teflon and metal portions of the DM-2 needle.
Solution c): Replace with a fresh cartridge. Return the defective cartridge to Xandex for test confirmation and warranty replacement.

Cause d): The Plunger Stop Assembly is not being used or is being used improperly (DM-1, 5 Mil cartridges only).
Solution d): Install a Plunger Stop Assembly and make sure that it is set at 1.25 turns from maximum. Carefully remove any excess ink from the needle using a lint-free tissue or swab before continuing with inking operation.

Related Information: See Plunger Stop Assembly section of the electric inking section.

Cause a): Ink cartridge is empty.
Solution a): Replace with a fresh cartridge.

Cause b):Air bubbles in the ink (pneumatic systems only). This sometimes occurs during the initial 1,000 ink dots from a new cartridge.
Solution b): Run 1,000 dots onto a test wafer. This should eliminate any bubbles that may have been present inside of the cartridge.

Cause c): The Teflon tubing (DM-2) or filament (DM-1) at the needle tip is worn or abraded. If burrs develop on the needle tip or filament, the cartridge can sometimes splatter ink.
Solution c): Replace with a fresh cartridge. Make sure that the Z-height setting is properly adjusted so that the needle tip or filament will not become abraded.

Cause d): Ink solvents have evaporated and partially cured the ink at the needle tip. If the splatter only occurs on re-start after long periods of down time, this may be the cause. Solvent evaporation changes the viscosity of the ink at the needle tip, making it more "sticky" and prone to splatter.
Solution d): Remove any excess ink from the needle tip using a tissue or swab saturated with DieMark Ink Remover or acetone prior to re-starting the inker after long periods of down time.

Cause e): 6993 ink used in hot chuck applications only. Condensation of ink solvent vapors on the needle tip can lead to solvent build-up and periodic deposition on the wafer under certain conditions. This will only occur in low yield off-line applications where large numbers of ink dots are placed rapidly with a very close spacing.
Solution e): Xandex does not recommend the use of 69xx series inks with a hot chuck.

1. Reduce the inking speed and/or change the chuck temperature.
2. Wipe off the needle tip with a lint free cloth or swab if any significant of accumulation of ink solvent is observed.

Cause f): Ink backflow is occurring at the top of the cartridge (DM-1, DM-1.25 filament cartridges only).
Solution f): See causes and solutions for preventing ink backflow at item 15.

Cause g): (Pneumatic Only) Ink cartridge is not screwed into the cartridge connector properly.
Solution g): Check cartridge connection to inker. Ensure that the connector is screwed firmly into the cartridge and that the cartridge threads are not stripped or damaged. Replace cartridge if necessary.

Cause a): Partially cured ink, still soft enough to be sticky / tacky, has accumulated on the outside of the cartridge needle. When ink build-up makes contact with the wafer surface a small amount attaches and is stretched into threads / strings as the wafer moves to the next die.
Solution a): Carefully remove any visible ink deposits from the outside of the cartridge needle and needle tip using solvent (DieMark Ink Remover is recommended) and a lint-free tissue. Take care not to damage the filament (DM-1) or Teflon tube (DM-2). Inspect cartridge needle at regular intervals and clean as required to prevent ink accumulation on the needle.

Cause a): Dot size setting on the pneumatic controller is too high (pneumatic systems only).
Solution a): Decrease the dot size setting.

Cause b): Air pressure to pneumatic controller is too high (pneumatic systems only).
Solution b): Set the air pressure to the pneumatic controller at 70 ±10 psi on all controllers except Motorized Z controller which should be set to 80 ± 5 psi.

Cause c): The cartridge size is too large.
Solution c): Change to a smaller cartridge size.

Cause d): Dot size potentiometer is defective (pneumatic systems only).
Solution d): Run Diagnostics Test B described in Controller Diagnostics section of the Operations manual. If test results are not within specified parameters, contact Xandex Customer Service to replace dot size potentiometer.

Cause e): Ink is being placed onto a surface with an unusually high surface energy. Depending on the type of material, spreading behavior and size of the ink droplet may vary significantly.
Solution e): Switch to a different cartridge size and/or a higher viscosity ink. If using a DM-2 cartridge, reduce the Dot Size Setting to compensate for the larger dots.

Cause f): The ambient temperature is higher than the recommended maximum temperature listed on the cartridge packaging (or higher than your normal operating temperature). Ink viscosity is lower at higher temperatures. Lower viscosity leads to larger ink dots. Storage and inking temperatures should be below 77 F (25 C) if possible.
Solution f): Reduce the cartridge storage and inking temperature to the recommended range: Storage = 50-77 F (10-25 C). Inking = 67-77 F (19.5-25 C).

Cause g): Ink has dropped below the specified viscosity range. This should not occur under normal conditions, as long as the cartridges are not past their expiration date and have been stored and used properly. Some inks, however, will experience viscosity changes if exposed to temperature extremes during shipping.
Solution g): Return sample cartridges to Xandex for testing and possible warranty replacement.

Cause h): The die surface contains channels that are causing the ink to “wick” to the adjacent die via capillary action.
Solution h): Place the ink dot in a different location on the die. Reduce the ink dot size if possible (use a smaller cartridge and/or reduce dot size setting).

Cause a): Ink dots were not cured at sufficiently high temperature. Very aggressive post-probe processes may require a high temperature cure, regardless of ink type being used.
Solution a): Increase cure temperature and duration to 150° C for 30 minutes.

Cause b): Post-probe process is too aggressive.
Solution b): If possible, take steps to make the post-probe process less aggressive (reduce solvent exposure time, etc.). If using a filament inker, also try a 7224 type ink.

Cause a): Dot diameter is too large.
Solution a): Reduce ink dot diameter to get acceptable dot height by decreasing dot size setting (pneumatic systems) or changing cartridge type to a smaller size.

Cause b): Ink type is wrong for the application.
Solution b): Switch to an ink type that will give a smaller dot height at a given dot diameter. As a general rule, the dot height relationship between inks is as follows: 699x series > 8103 > 7824 > 8104.

Cause a): Wafers were placed in a confined area with no ventilation.
Solution a): Cure the wafers in a more open area with better ventilation.

Cause b): Ink dots are taller than normal. Ink is being placed onto a surface with an unusually high surface energy. Depending on the type of material, spreading behavior and height of the ink droplet may vary significantly.
Solution b): Increase the wafer cure time and/or increase the surface energy of the wafer.

Cause c): Ink dot spacing on the wafer is more concentrated than normal. If the ink dots are being cured in an area with low air flow, large numbers of ink dots placed very close to each other may take up to twice as long to cure as ink dots that are widely spaced. For instance, ink dots on a wafer with a 99% yield of good die would dry much faster than ink dots on a wafer with only a 1% yield of good die.
Solution c): Increase the amount of air flow going across the surface of the wafers.

Cause d): The ambient temperature in the curing area is lower than normal.
Solution d): Increase the temperature in the curing area to normal levels.

Cause e): Batch specific ink problem. This is unlikely since all Xandex air curing ink batches are tested to confirm proper cure time prior to loading into cartridges.
Solution e): Return sample cartridges to Xandex for test confirmation and possible warranty replacement.

Cause a): Dot size setting is higher than normal (pneumatic systems only). Higher dot size setting causes larger ink volume/dot which results in fewer dots/cartridge.
Solution a): Reduce dot size setting if possible.

Cause b): Dot counter was accidentally reset (pneumatic systems only).
Solution b): Take any necessary steps (training, etc…) to ensure that the counter is not reset at an inappropriate time.

Cause c): Ink cartridge is clogged (pneumatic systems only).
Solution c): Replace with a fresh cartridge. Return the suspect cartridge to Xandex for test confirmation and possible warranty replacement.