Ultra Pure Chemicals
Bases
Ammonium Hydroxide Solutions
Ammonium Hydroxide may be mixed with Hydrogen Peroxide and De-ionised Water as part of the RCA or SC1 cleans for prefurnace silicon wafer cleaning. This mixture creates an alkaline environment which oxidises the silicon surface, particles are then lifted from the surface by the underetching of the silicon layer. The equilibrium between particle removal efficiency and silicon roughening is affected by the concentration of ammonia used (typically 0.5 : 1 : 1, Ammonia: Hydrogen Peroxide: De-ionised Water). Usually bath temperature is around 65°C. There is an increasing trend towards more dilute chemistries.
Market Segments:
Functions:
Cleaner