公开(公告)号：JPS6320837A

公开(公告)日：1988-01-28

申请号：JP13200587

申请日：1987-05-29

Applicant: IBM

Inventor： GRAF VOLKER ,  MOHR THEODOR OSKAR ,  BUCHMANN PETER LEO ,  VETTIGER PETER ,  HOH PETER DAVID

IPC: H01L21/033 ,  H01L21/285 ,  H01L21/311 ,  H01L21/318 ,  H01L21/336 ,  H01L21/338 ,  H01L29/812

公开(公告)号：GB1180186A

公开(公告)日：1970-02-04

申请号：GB1623568

申请日：1968-04-04

Applicant: IBM

Inventor： DRANGEID KARSTEN ELVIN ,  MOHR THEODOR OSKAR ,  STATZ HORST FRANZ ,  MUENCH WALDEMAR VON

IPC: H01L29/00 ,  H01L29/812

Abstract: 1,180,186. Semi-conductor devices. INTERNATIONAL BUSINESS MACHINES CORP. 4 April, 1968 [18 April, 1967], No. 16235/68. Heading H1K. Two heavily doped highly conductive areas 46, 47 are provided on a substrate 41 beneath the weakly doped channel layer 42 between the source 43 and the gate 44, and the gate 44 and the drain 45, of a Schottky-barrier field-effect transistor to improve its transconductance. The transistor may be made of germanium, silicon or gallium arsenide and the substrate may also be of sapphire, the channel layer being epitaxially grown over the highly conducting areas and the substrate. A similar device, Fig. 5, not shown, can be made by planar techniques. In such cases the highly conductive areas may be in the form of composite layers, Fig. 7, not shown, the lower sub-layers being of successively higher conductivity than the sub-layers above them. In other embodiments the highly conductive areas are grown on top of the channel layer, Fig. 3, not shown, or actually form part of it, Fig. 2, not shown.

公开(公告)号：DE3685495D1

公开(公告)日：1992-07-02

申请号：DE3685495

申请日：1986-07-11

Applicant: IBM

Inventor： GRAF VOLKER ,  MOHR THEODOR OSKAR ,  BUCHMANN PETER LEO ,  VETTIGER PETER ,  HOH PETER DAVID

IPC: H01L21/033 ,  H01L21/285 ,  H01L21/311 ,  H01L21/318 ,  H01L21/336 ,  H01L21/338 ,  H01L29/812 ,  H01L21/00 ,  H01L21/28

Abstract: Undercut mask profiles are formed in a semiconductor process by depositing a first plasma CVD nitride layer followed by a second plasma CVD nitride layer at a different excitation frequency, so that the two layer have different etch rates; and patterning and etching the double layer structure to form the desired undercut profile. Method is simple and easy to control and the undercut profile has good temp. stability. The nitride layer are SiNx, SiOxNy or BNx. The gas compsn. for each CVD stage is different, pref. NH3, N2 and SiH4 for the first stage; and N2 and SiH4 for the second stage. The RF frequency is 1-50 MH2 for the first stage and below 100 MHz for the second stage.