Pre-Diffusion cleans are used to prepare substrates for subsequent high temperature processing. Both the cleans bench and the subsequent high temperature processing steps have the strictest contamination requirements in the cleanroom. (For more about the contamination categories, please visit the Cleanliness (previously Contamination) Groups page).
The cleans generally consist of SC1 (short for Standard Clean 1) and SC2 (short for Standard Clean 2) and an optional HF (Hydrofluoric Acid) dip to remove organic particles and contaminants, metallic particles and contaminants, and native oxides respectively.