LOR 10B

About this Process
Process Details
Equipment	LOR 10B
Technology	Lift-off

LOR 10B is a lift-off resist polydimethylglutarimide (PMGI) that is desinged for lift-off process and sacrificial release layers. It is used in combination with conventional photo resist to create and undercut or step feature facilitating clean and easy liftoff minimizing, or eliminating stringers and edge roughness. LOR 10B dissolves in Remover PG. Acetone can be used to dissolve the PR layer and do the initial liftoff but Remover PG must be used to remove the LOR 10B. It is always recommended to do a double bath of Remover PG followed by IPA, and then water rinses.

Procedure

Steps for LOR 10B process on a 4" or 6" silicon substrate

1. Clean substrate
   • O₂ Plasma
   • Nanostrip
   • Acetone/IPA
2. Dehydration bake 110-115C 1-2 min
3. Spin LOR for 30s
   1. Speed and thereby thickness will depend on thickness of metal
   2. Thickness should be at least 1.5x the thickness of the metal
   3. Thickness should be < 1/3 minimum space between structures
   4. For thickness vs. spin speed see LOR data sheet
4. Bake at 190C 5 min
5. Spin 1813 @ 4krpm 30s
6. Bake at 110C for 4 min
7. Expose 6-8.5s on MA6 (approximately 0.25s on stepper)
8. Develop Options
   1. Spray for 20 - 30s MF300. Check for double line around feature
   2. Puddle DP25-25 or 30-30. Check for double line around feature.
9. If it needs more develop time develop additional 5s
10. Evaporate or sputter metal
11. Soak in 65-80C remover PG for 15 - 30min, ultrasonic is usually not be necessary
12. Rinse