Cageless Process - LPCVD
Original Publication Date: 1983-Sep-01
Included in the Prior Art Database: 2005-Feb-07
Low pressure chemical vapor deposition (LPCVD) of doped polysilicon on silicon wafers has been traditionally performed with the wafers inside a cage which is then inserted into the tube of the furnace in which the process is carried out. It has now been found that such cages can be eliminated provided the edge of the wafer is maintained 17.5 mm or less from the wall of the furnace tube. Larger wafer-to-wall tube spacing does not provide a uniform film on wafers which are 100 mm or more in diameter.