Silicon surface treatment in BF3 + H2 and BF3 + H2 + CF4 plasma

Abstract

The method of creating ohmic contacts to the p-region of silicon by sputtering molybdenum in a BF3 plasma makes it possible to obtain the minimum transient resistance of the Mo/p+Si system before heat treatment (0.09 Ohm). This value is 4.4 times less than when molybdenum is sputtered in Ar plasma. With this processing method, it was shown that the minimum value of the transient resistance is slightly higher than when sputtering molybdenum by the magnetron method when using additional processing of a silicon wafer with active regions in a peroxide-ammonia solution, followed by holding the wafer in a vacuum of 410-3110-4 Pa for 3050 minutes at a temperature of 250350 C and re-treatment in a peroxide-ammonia solution before applying molybdenum (0.07 Ohm).