| 摘要 |
Silicon wafers are cleaned by first immersing them in a film forming solution which reacts with the dirty wafers to form a film on the wafers and then immersing the wafers in a film stripping solution which removes the film. For silicon wafers both the film forming solution and the film stripping solution may be formed from separate aqueous source solutions comprising 49% HF by weight and 70% HNO3 by weight, respectively. The film forming solution comprises 99.1% to 99.5% by volume the HF solution and 0.5% to 0.9% by volume the HNO3 solution. A small quantity of a wetting agent may be present in this solution. The stripping solution comprises 95% to 99% by volume of the HNO3 solution and 5% to 1% by volume of the HF solution. When utilized at room temperature the film forming solution forms a film on the wafers and the stripping solution removes the film with a minimum of attack on the silicon of the main wafer body. This silicon wafer cleaning method is successful with all silicon wafers independent of doping level. |
