Impurity Gettering and Removing Gettered Impurities
Original Publication Date: 1978-Feb-01
Included in the Prior Art Database: 2005-Feb-20
The impurity gettering process involves argon implantation gettering on the backside of the silicon (Si) wafer at the beginning of the device processing steps. The detailed process is as follows: 1. Oxidize the starting Si substrate in dry O(2) at 970 degrees C for 20 minutes to grow 250 angstroms SiO(2) on the surfaces of the substrate. 2. Implant argon (Ar) at the back surface of the Si substrates through the thin SiO(2) with a dosage of about 6 x 10/15/ atoms/cm/2/ and at 150/2/ to 200 KeV. 3. Heat treat the wafer at 1000-1100 degrees C for 60 to 180 minutes in an inert gas to getter the impurities to the Ar implant damaged layer. 4. Chemical vapor depositing about 500 angstroms Si(3)N(4) at 1000 degrees C onto the implant gettered side of the wafer. 5.