公开(公告)号：DE1639263B1

公开(公告)日：1971-08-26

申请号：DEJ0035441

申请日：1968-01-08

Applicant: IBM

Inventor： BARSON FRED ,  KUEHN RICHARD THEODORE ,  PALMER MYRON DOUGLAS

IPC: H01L21/00 ,  H01L21/033 ,  H01L23/29 ,  H01L23/485 ,  G03C5/06

Abstract: 1,203,341. Etching. INTERNATIONAL BUSINESS MACHINES CORP. 4 Jan., 1968 [9 Jan., 1967], No. 662/68. Heading B6J. [Also in Division H1] An opening is etched in a film by forming a first layer of photoresist on the film, exposing the layer through a first mask to form a first pattern, thereafter exposing the first layer, or a second layer formed over the first layer, through a second mask to form a second pattern which overlaps the first pattern, the area of overlap defining the opening developing the layer(s) and etching the exposed surface of the film. The film may be an insulating layer 12 (e.g. silicon or germanium oxide, silicon nitride, alumina or glass) provided on a semi-conductor substrate 10 (e.g. silicon or germanium). A first photoresist layer 14 is exposed thzough a first mask and developed to produce a first aperture 16 and a second photoresist layer 18 is exposed through a second mask and developed to produce a second aperture 22. The exposed area of layer 12 is etched (e.g. with buffered H.F.). The aperture defined by the second mask may be larger than that defined by the first mask (e.g. the second aperture may encompass two smaller first apertures). In an alternative procedure a single photoresist layer may be exposed successively through first and second masks. The photoresist may be stripped from the etched layer 12 and a P or N region 26 diffused in to provide a collector, base or emitter region or an isolation or inversion preventing region. In a further example, Fig. 2, two photoresist layers 14A and 18A are exposed through separate masks as above to produce an aperture 22A in an insulating layer 12A composed of glasses or silicates. The aperture permits a metal contact 28A to be provided and to form a terminal contact to a metal land 13 which is in ohmic contact with a semi-conductor region 10A.