Werner Kern developed the basic procedure in 1965 while working for RCA, the Radio Corporation of America.
[1][2][3] It involves the following chemical processes performed in sequence: The wafers are prepared by soaking them in deionized water.
[2] The first step (called SC-1, where SC stands for Standard Clean) is performed with a solution of (ratios may vary)[2] at 75 or 80 °C[1] typically for 10 minutes.
This treatment effectively removes the remaining traces of metallic (ionic) contaminants, some of which were introduced in the SC-1 cleaning step.
[2] The first step in the ex situ cleaning process is to ultrasonically degrease the wafer in trichloroethylene, acetone and methanol.