Method of manufacturing semi-conductor devices

Claim 2

A method as claimed in claim 1, wherein the metal layer mask is provided in a self-registered manner by depositing metal on the insulating layer and at the aperture therein and subjecting the body to high frequency acoustic vibrations to remove the metal from the insulating layer except at the aperture therein where the metal remains adhering to the semiconductor body surface portion to form the said metal layer mask.

Claim 3

A method as claimed in claim 1, wherein the aperture in the insulating layer is provided by a photolithographic and etching technique including providing an opening in a photo-resist pattern, the same opening in the photo-resist pattern being employed to define the aperture in the insulating layer and the metal layer mask in registration therewith.

Claim 4

A method as claimed in claim 4, wherein After providing the aperture in the insulating layer, the metal mask is provided in a self-registered manner by depositing metal on the photo-resist pattern on the insulating layer and at the said opening therein, after which the photo-resist pattern is removed to break away the metal thereon and leave the said metal layer mask at the aperture in the insulating layer and on the edge of the insulating layer at the aperture.

Claim 5

A method as claimed in claim 4, wherein the metal mask is provided in a self-registered manner by providing the photo-resist pattern on a first metal deposited on the insulating layer, the aperture in the insulating layer is defined by etching at an opening in the first metal defined by etching at the said opening in the photo-resist pattern, subsequently the first metal etched further laterally to space the edge of the opening formed in the first metal from the edge of the aperture in the insulating layer, the photo-resist pattern is removed and a second metal is deposited on the first metal and at the said opening formed therein, and the first metal is removed to break away the second metal thereon and leave the said metal layer mask at the aperture in the insulating layer and on the adjacent portion of the insulating layer around the edge of the aperture.

Claim 6

A method as claimed in claim 1, wherein prior to the said ion implantation, a shallow surface layer of the said opposite conductivity type is provided where the said other surface region and the adjacent portion of the one surface region are to be formed, and, by the said ion implantation, there is provided in the shallow surface layer where the said adjacent portions of the one surface region are to be formed an impurity c0ncentration of the one conductivity type greater than that of the said opposite conductivity type present therein, the portion of the shallow surface layer where the said other surface region is to be found being at least partially masked by the metal layer mask against the said ion implantation so as to remain the said opposite conductivity type.

Claim 7

A method as claimed in claim 1, wherein the one surface region forms with the said other surface region a p-n junction which terminates at the surface of the semiconductor body below the insulating layer, and the aperture in the insulating layer is later employed to receive a metal layer electrode provided thereat to provide a contact to the said other surface region.

Claim 8

A method as claimed in claim 1, wherein introduction of impurity atoms of the said opposite conductivity type is effected into the semiconductor body portion at the aperture while the insulating layer masks the underlying semiconductor body portion against the impurity introduced.

Claim 9

A method as claimed in claim 9, wherein the said introduction of impurity atoms of the said opposite conductivity type is effected by thermal diffusion to form a p-n junction spaced laterally from the aperture edge.

Claim 10

A method as claimed in claim 1 wherein the metal mask acts only to partially mask the underlying semiconductor body whereby there is formed in the body a one surface region containing a less heavily doped one type portion under the metal mask and a more heavily doped extrinsic one type portion surrounding the less heavily doped portion, said other surface region being formed by overdoping a surface portion on the less heavily doped one type portion.

Claim 11

A method as claimed in claim 11 wherein a contact is made to the extrinsic portion to serve as a base contact, and a separate contact is made to the overdoped surface portion to serve as an emitter contact.

Claim 12

A method as claimed in claim 1 wherein the metal mask is removed after the ion-implantation step to make available again the aperture in the insulating layer.