Note: Make sure wafers have never had GaAs or metal on them and have not been in any GaAs or metal contaminated equipment or contaminated beakers.

If wafers have been scribed or have resist on them they should get the resist strip process prior to this clean procedure.

NOTE: USE CLEAN DESIGNATED QUARTZ BEAKERS (NONMETAL)!

PROCESS

• 10 minutes in H₂SO₄:H₂O₂ (4:1) @ 90 C
• Dump Rinse (std 6 cycles) OR overflow rinse for 5 minutes
• 10 minutes in H₂O:HCl:H₂O₂ (5:1:1) @ 70 C
• Dump Rinse (std 6 cycles) or overflow rinse for 5 minutes
• 15 seconds in HF (50:1) @ room temp
• Dump Rinse (std 6 cycles) or overflow rinse for 5 minutes
• Blow dry using N2 gun

Note: Wafers must be loaded into furnaces within 1 hour after clean -- or re-clean them.