DE1044286B - Method for producing a semiconductor arrangement, for example a directional conductor or transistor - Google Patents

Description

GERMAN

It is known (J. W. THey and R. A. Williams, Proc. IRE, 41 [Dec. 1953], pp. 1706 to 1708; R. F. Schwarz and J. F. Walsh, Proc. IRE, 41 [Dec. 1953], pp. 1715 to 1720), the surface of semiconductors, preferably semiconducting crystals, in general single crystals, to be treated electrolytically, in particular to be removed and then by polarity reversal of the electrolyte process to be electroplated. In this way one has n-p-n or p-n-p transistors made from germanium by placing the germaniium single crystal on two opposite sides the described treatment of the germanium surface was carried out. It was for example an indium plating applied to germanium after the previous Electrolytic removal of the surface produces a thin layer of germanium of a precisely defined thickness had been. The germanium inter-schiclit served as a base during the two metal fencing layers served as emitter and collector and were provided with appropriate connections.

It has also been proposed that said metal layers also in other ways, for example by chemical treatment, possibly by ion exchange, and also the removal or cleaning of the surface before the application of the metal layer by other methods, for example in a purely chemical way.

The studies on which the invention is based have now shown that it is indeed necessary is, by the pretreatment Fretndscbichten, in particular oxide layers, z. B. porous oxide layers, Tarnish layers, etc., from the surface of the semiconductor crystal, in particular 'single crystal, to remove; However, that it is disadvantageous, the metal layer on the absolutely bare semiconductor surface to arrange.

The invention therefore relates to a method for producing a semiconductor arrangement, for example Directional conductor or transistor, with one between a metal layer and the surface of the semi-conductor terkristalls generated surface layer. According to the invention an improved locking effect, in particular a very sharply bent and steep voltage characteristic, the semiconductor arrangement achieved in that the between the semiconductor crystallil and the semiconductor surface located on the metal layer first extremely cleaned and on the of every foreign layer is freed of the semiconductor surface by appropriate further surface treatment an inherently pure, homogeneous, coherent, very thin compared to the edge layer, for example Vioo μ thick oxide layer is generated, on which the metal layer is then applied.

Method of Manufacture

a semiconductor device,

for example Rictitleiter or transistor

Applicant:

Siemens & Halske Aktiengesellschaft,

Berlin and Munich,
Munich 2, Witteisbacherplatz 2

Dr. Alfred Politycki, Karlsruhe,
has been named as the inventor

In the case of silicon, for example, a silicon oxide layer is formed generated, which can be monoxide, silicon dioxide or a combination of both. It is important that this layer is inherently pure, homogeneous and! is as coherent as possible. Besides, it is expedient if the oxide layer is thin, possibly 'about Vioo μ, or even only one or a few Molecular layers is strong.

According to a particular. This foreign layer thereby becomes the development of the inventive concept generated that initially the semiconductor surface by a known or proposed treatment method extremely cleaned and freed from any foreign layer, whereupon in more targeted Orphan a foreign layer of desired small thickness in front of the metal plating on the surface is generated again. This can be done, for example, that the semiconductor surface after the pretreatment briefly · - ■ if necessary for a few minutes or even just a few seconds · - a liquid or gaseous medium and / or a suitable irradiation is exposed, wherein the liquid or the atmosphere or the radiation are selected such that a thin foreign layer, for example oxide layer, forms on the semiconductor surface. It begged for example as. proved to be sufficient to briefly remove the semiconductor crystal after the pretreatment Exposure to air and / or exposure to a slightly acidic liquid; also an irradiation with ultraviolet light or with X-rays, suitably in an oxygen-containing atmosphere, for example in air, has been found to be suitable.

809 679/277

Subsequent to this treatment, the surface is then metallized according to one of the "der in the" Introduction of indicated known or · - · proposed processes. ·

According to a further development of the inventive idea depends on the mode of action of the oxide layer and thus the question of which type of oxide layer is applied should be, both from. Conduction type · of the semiconductor —ρ or η - as well as of the cladding material away. For example, n-leitenidem Silicon, an oxide layer from copper and gold plating, has proven its worth.

Claims (8)

Patent claims: 1. Method for manufacturing a semiconductor device, for example directional conductor or transistor, with one between a metal layer and the surface of the half-leather crystal produced edge layer, characterized in that the semiconductor surface located between the semiconductor crystal and the metal layer initially extremely cleaned and on the semiconductor surface freed from every foreign layer by appropriate further surface treatment a pure, homogeneous, coherent, in comparison very thin oxide layer, for example Vioo μ thickness, is produced for the edge layer on which the metal layer is then applied. 2. The method according to claim 1, characterized in that that the oxide layer is produced with a thickness of one or several molecular layers. 3. The method according to claim 1 and 2, characterized in that the semiconductor surface for Generation of the thin oxide layer exposed to a liquid and / or gaseous medium will. 4. The method according to claim 3, characterized in, that the surface treatment - preferably with .nj-conductive silicon - on acidic Ways is carried out. 5. The method according to any one of claims 1 to · 4, characterized in that the semiconductor surface to produce the thin oxide layer is irradiated with ultraviolet light. 6. The method according to claims 1 to 5, characterized in that the treatment to produce the oxide layer briefly, in particular. a few minutes or seconds. / 4 * -. "". 7. The method according to ¹ one of claims 1 to 6, characterized in that: ~ \ that a semiconductor single crystal unld as the semiconductor material germanium, - silicon or an alloy; the III. and V. or II. and VI. Group of the Periodic Table is used. .-. '--- 8. The method according to any one of claims 1 to 7, characterized in that copper, silver and / or GaH is used as the metal layer. Considered publications:
German Patent No. 823,468;
U.S. Patent No. 2,497,770;
G. J 00 s, Physics of Solid Bodies, Vol. 9, Part II, 1948, pp. 108, 109. © SOS 679/277 11.58.