公开(公告)号：US3901744A

公开(公告)日：1975-08-26

申请号：US43630074

申请日：1974-01-24

Applicant: INT STANDARD ELECTRIC CORP

Inventor： BOLGER DEREK E ,  PION MARTIN

IPC: H01J9/12 ,  H01L21/00 ,  H01L21/208 ,  H01L21/306 ,  H01L7/38

CPC classification number: H01L21/30612 ,  H01J9/12 ,  H01L21/00 ,  H01L21/02395 ,  H01L21/02463 ,  H01L21/02546 ,  H01L21/02625 ,  H01L21/02639 ,  Y10S438/928 ,  Y10S438/977

Abstract: A method of making a semiconductor device avoids the problems of excessive liquid phase epitaxial growth at the edges of a slice which can interfere with processing in a sliding boat technique. A layer of refractory masking material is deposited on the front and back surfaces of the substrate slice. The central area of the front surface is then etched to leave the protective layer on the sides, edges and back. This prevents the undesired growth at the sides during the subsequent steps of growing semiconductor layers on the substrate. The slice is placed in a recess in a graphite boat having a sliding portion containing melts which contact the slice to grow first and second semiconductor layers. The central area of the back masking layer and substrate are then etched away to expose the first layer.