Ink Curing Guidelines

Ink curing time and temperature varies with ink type. Click the tab for each ink type for specific curing information. To remove ink dots use DieMark Ink Remover 8000. Scroll down for ink removal instructions HERE.

Ink cure testing performed on single, (not stacked in a wafer boat/cassette) polished silicon wafers with dot spacing of 50 mil (1270 µm) with moderate air flow at 70-72 °F (21.1-22.2 °C).

Note: Markem® is a registered trademark of Markem-Imaje, a Dover Company, Kennesaw, GA, USA

8103 & 8104 Curing Description
Cure Mode Hard Cure
Temperature Ambient Temperature
Cure Time Varies by dot size:
5-15 minutes for ≤15 mil
15 minutes - 3 hours for 15-25 mil dots.
3-6 hours for 25-40 mil dots.
Longer time is required for larger dot sizes.
Result Ink is highly resistant to most post-probe processes.
Cure Mode Hard Cure
Temperature 150 Watt heat lamp at 5-6 inches OR 110-150 °C oven.
Cure Time 5-10 minutes
Result Ink is highly resistant to most post-probe processes.
Note: Phenoxy inks that have air-dried will not smear when touched. 8103 and 8104 are highly resistant to most post probe handling and processes. A room temperature cure will give good results for the vast majority of applications. In applications where the ink will be subjected to very harsh process conditions or if the ink is not giving acceptable adhesion results, a cure of 150 °C for 30 minutes is recommended. See more 8103 curing guidelines here.
Markem 69XX Curing Description
Cure Mode Soft Cure
Temperature 70-100°C
Time 5-15 Minutes
Result Ink is semi-permanent and will not withstand wash of alcohol, acetone, or photoresist removers.
Cure Mode Hard Cure
Temperature 150-185°C
Time 30-60 Minutes
Result Ink is highly resistant to most wash processes.
Note: Phenoxy inks that have air-dried will not smear when touched. These inks should be cured/baked within 2 hours of inking to reduce risk of cracking.
7824 and 7824T Curing Description
Cure Mode Hard Cure
Temperature Ambient Temperature
Time 1-3 hours for ≤20 mil dots
3-4 hours for 20-25 mil dots
4-10 hours for 25-40 mil dots
Cure Mode Hard Cure
Temperature 150 Watt heat lamp at 5-6 inches OR 110-150°C oven.
Time 5-10 minutes
Result Ink is highly resistant to most post-probe processes. A room temperature cure will give good results for the vast majority of applications. In applications where the ink will be subjected to very harsh process conditions or if the ink is not giving acceptable adhesion results, increasing the cure temperature and time to 150 °C for 30 minutes is recommended.
7224 Curing Ink Description
Cure Mode Hard Cure
Temperature 125-150°C
Time 30-45 Minutes
Result Ink is highly resistant to most wash processes.
Note: Air-drying or soft cure are not recommended for 7224.

Ink Curing Information

Ink Curing Information

The procedure for curing will depend on the type of ink used and other factors such as dot size and spacing (see “General Notes on Ink Curing, below). Xandex guidelines are developed under laboratory conditions using single wafers and are intended as a baseline to develop a curing process that meets your specific needs.

Markem® 6990, 6993, and 6997 should be cured/baked within 2 hours of inking due to the evaporation of solvents in the ink over time. If a wafer (or boat of wafers) is left uncured for an extended period of time, the dots may crack and/or flake after the baking process.

Markem® 6990, 6993, and 6997 inks, when air-dried, will not smear when touched. They are not permanent, however, and will not withstand most post-probe handling or processes. Conversely, Xandex 7824 and 7824T inks air cure within 2.5 hours (≤20 mil, up to 10 hours for >20 mil dots). Xandex 7824 and 7824T may also be heat cured at up to 150°C for 10 minutes.

Xandex 8103 and 8104 Glycol Free inks hard cure under ambient conditions in the least time of any of the inks offered by Xandex. Ink dots of <25 mil typically air dry to a hard cure in 45 minutes. Dot sizes >25 mil may require significantly longer to cure. An ambient cure time of up to 6 hours may be needed for larger dot sizes. Xandex 8103 and 8104 may also be heat cured at up to 150°C for 10 minutes if a faster cure is desired.

General Notes on Ink Curing

General Ink Curing Guidelines

Several factors have greater influence on the time required to get a full cure in the shortest amount of time, either when heat curing or curing at room temperature:

  • Dot Size: Larger dot sizes will require longer cure times.
  • Dot Spacing: Large numbers of closely spaced ink dots will require a longer cure time than small numbers of widely spaced dots.
  • Air Flow: Continuous air flow across the wafer surface will reduce the amount of time required for ink curing. This is especially important when air curing at ambient temperatures.
  • Wafer/Die Surface: Both the surface chemistry and degree of patterning on the die affect how the ink spreads on the wafer. If the ink does not spread as much, the dots will be thicker. And if the dots are thicker, they will require a longer cure time.
  • Temperature: Higher temperatures will lead to faster ink cure times.
  • Wafer Boat / Cassette: Wafers stacked in a boat / cassette will require increased cure time compared to single wafers.

Ink Removal

Removing Xandex Inks

If a wafer is washed immediately after probing, a rinse with isopropyl alcohol or acetone generally removes all inks completely. Xandex highly recommends DieMark® Ink Remover 8000 to remove all Xandex supplied inks, even after oven curing. For best results use full strength.

Xandex DieMark® Ink Remover 8000 may also be used in ultrasonic or circulating baths. This product accommodates other unique wafer cleaning methods such as step temperature and pressure ramping. Compare your cleaning equipment's solvent requirements with DieMark Remover to assure compatibility and safety before use. Safety Data Sheet (PDF)

Procedure A

  1. Apply sparingly with an eyedropper to a localized area of the wafer that needs to be cleaned.
  2. Allow DieMark® Ink Remover 8000 time to soak the ink dots (average time: 2-3 minutes). The time required will vary depending on the ink dot curing time and/or temperature.
  3. For highly cured or oven dried ink spots, use longer soak times, and wipe gently with a clean lint free cloth to facilitate removal.
  4. If necessary, repeat the above steps.
  5. For removal of ink from a large area, or from the entire wafer, soak a clean lint free cloth with DieMark® Ink Remover 8000 and apply the wet cloth onto wafer surface. Allow time to saturate the ink dots. Wipe afterwards.
  6. When desired ink spots have been removed, rinse wafer surface via standard procedures, such as vapor degreasing, and/or rinse with a clean solvent (Isopropyl Alcohol). A DI water rinse is recommended to remove trace solvent residue. A bake cycle at appropriate temps may be preferred to vaporize any organic residue left from rinse solvent.

Procedure B

Follow these steps if thorough removal of all trace residue is required.

  1. Ultrasonic bath of DieMark® Ink Remover 8000
  2. Wash wafer for 1-5 minutes
  3. Ultrasonic bath of acetone for 2 minutes
  4. Rinse with D.I. water
  5. Rinse with isopropyl alcohol
  6. Check under 30X or 40X magnification. If any residue remains, repeat the process keeping the solvent bath low (1-2 minutes)
  7. Air dry

Note: a gentle wipe using a lint-free cloth or tissue may be necessary to remove all traces of residue.

Other Methods

Based on customer feedback, here are additional methods that have proven effective.

Methyl Ethyl Ketone (MEK) or N-Methyl-2-Pyrrolidone (M-Pyrrol); follow these steps:

  1. Ultrasonic bath of warm solvent (40-50°C).
  2. Wash wafer for 1-5 minutes.
  3. Ultrasonic bath of acetone for 2 minutes.
  4. Rinse with D.I. water.
  5. Rinse with isopropyl alcohol.
  6. Check under 30X or 40X magnification. If any residue remains, repeat the process keeping solvent bath low (1-2 minutes).
  7. Air dry.

Markem® 540 Cleaner (Not recommended for 8103 ink) – follow these steps:

  1. Ultrasonic bath of warm solvent (40-50 °C).
  2. Wash wafer for 30-60 seconds.
  3. Rinse with D.I. water.
  4. Rinse with isopropyl alcohol.
  5. Air dry.

Aptek® Remover #6515 – follow these steps:

  1. For best results use full strength.
  2. Apply sparingly with an eyedropper to a localized area of the wafer.
  3. Allow Aptek 6515 time to solvate the ink spots (2-3 minutes). Time required will vary depending on the time and temperature that the epoxy was cured.
  4. For highly cured ink spots, use longer soak times, and wipe gently with a clean lint free cloth to facilitate removal. If necessary, repeat steps 2, 3, and 4.
  5. For large area or removal of ink from total wafer area, soak a clean lint free cloth with Aptek and lay wet cloth onto wafer surface.
  6. Allow time tosoak/solvate ink. Then remove cloth and wipe dry.
  7. When desired ink spots have been removed, clean wafer surface via standard procedures, such as vapor degreasing, and/or rinse with a clean solvent (Isopropyl Alcohol) followed by a bake cycle at 65°C to dry.

Note: Aptek 6515 is a product of Aptek Laboratories, Inc., Valencia, California, USA