HMDS

Hexamethyldisilazane (HMDS) is a common primer used before spin coating that serves as an adhesion promoter for photoresist.

Hexamethyldisilazane (HMDS)

1. HMDS jar

This is not available anymore.

The dehydrated substrate is put into a vacuum desiccator where HMDS is stored in a petri dish. Then, the desiccator is pumped down for 5 min to vaporize HMDS for priming.

2. Spin-coat MicroPrime MP-P20

Microprime MP-P20 (ShinEtsu MicroSi, Inc.) is a mixture of 20% HMDS and 80% propylene glycol monomethyl ether acetate (PGMEA), a common resist solvent.

Example of recipe (Ref. MicroPrimeHPPrimerDataSheet‎)

1. Place wafer on spinner chuck and pipette enough MP-P20 to cover entire surface
2. Leave for a minimum of 10 sec
3. Spin: 3000-5000 rpm, 30 sec
4. Bake: 100-150 °C, 1-3 min

3. YES Vapor priming Oven

YES Vapor Priming Oven in Penn Nanofab can coat HMDS vapor on the substrate in vacuum. The oven pumps down to dehydrate the samples, and then fills with pure HMDS vapor, resulting in a much more efficient prime than is possible otherwise.

Note: Spinning of HMDS is not allowed.