DE1210085B - Method for manufacturing electrical semiconductor components - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

HOIl

German class: 21g-11/02

Number: 1210 085

File number: J 21761 VIII c / 21 g

Filing date: May 12, 1962

Opening day: February 3, 1966

The invention relates to a method for producing electrical semiconductor components.

In the manufacture of semiconductor components, it is known to use various etching treatments Purposes.

For example, it is known to etch semiconductor bodies in order to close exposed parts of the pn junction clean. It is not intended to remove the semiconductor material by the etching substance.

Furthermore, one already has part of the surface layer by electrolytic etching on semiconductor bodies removed in order to attach a contact to an underlying layer can. the Parts of the surface that should not be removed are covered with a suitable material.

There were also silicon platelets already coated with nickel in the vicinity of the solder joint an ohmic electrode in order to obtain an almost ideal point contact.

Furthermore, a method has already been described, the task of which is the production of semiconductor components with extremely low base resistance. For this purpose, a metal layer is used down to a low resistance path between the rectifying junction and to create the part of the base zone where the base electrode is to be attached. To the metal layer to be able to apply as close as possible to the pn junction without the rectifying Junction is short-circuited, the semiconductor die should be etched so that the pn junction forms a channel.

The invention is based on the object of creating a semiconductor component which, at high Frequencies can be operated. It is essential that the capacity and thus the area their transition or transitions is as small as possible. This can be achieved, for example be that a large area transition is made and its size is reduced by etching.

However, the above-mentioned known methods are, insofar as they are at all, the removal of semiconductor material concern at the pn junction, not suitable for this, as this is a subsequent reduction in the pn junction area mechanically very unstable semiconductor components results. The invention avoids this disadvantage.

According to the invention, electrical semiconductor components are produced in such a way that a semiconductor body containing a pn junction and provided with electrodes is covered with insulating material, that the insulating material is removed so that a method for producing electrical
Semiconductor components

Applicant:

International Standard Electric Corporation,

New York, N.Y. (V. St. A.)

Representative:

Dipl.-Ing. H. Ciaessen, patent attorney,

Stuttgart 1, Rotebühlstr. 70

Named as inventor:

Carl Father Sandbank, London

Claimed priority:

Great Britain May 24, 1961 (18 743)

Part of the semiconductor body is exposed, and that then the semiconductor body next to and under a non-ohmic Electrode is etched away so that the area of the pn junction is reduced.

An example of the method according to the invention will be explained in more detail with reference to the drawing will. In Fig. 1 to 3 the individual stages of the method according to the invention are shown.

In the method step shown in FIG. 1, the semiconductor device consists of a germanium body 1 with a pn junction 2, which is obtained by alloying the alloy material 3 became. On the semiconductor body 1 and on the alloy pill 3, leads 4 are, for example, in Attached in the form of wires. The whole device was covered with a layer 5 of synthetic resin, e.g. B. covered with epoxy resin.

The next step is that part of the synthetic resin envelope 5 and the semiconductor body 1 is ground away so that an arrangement is obtained as shown in FIG. 2 is shown. As can be seen from the figure, the semiconductor body is ground so far that the pn junction 2 at 6 is exposed.

Finally, the arrangement that is made in the process step according to FIG. 2 was immersed in a bath containing potassium hydroxide and one subjected to electrolytic etching process. Here is the exposed part 6 of the semiconductor body attacked, but not the alloy pill 3 and that Resin 5 dissolved. The etching process will be like this

"■" '' 609 503/297

continued for a long time until the semiconductor body 1 has been removed so far that the pn junction 2 provides the required has a small area.

Although, according to the example described above, the entire semiconductor body is covered with synthetic resin and then a part of the resin is to be removed by grinding, the procedure can also be such that the semiconductor body is only partially covered with synthetic resin, so that grinding is not necessary is. Part of the synthetic resin shell can also be removed by cutting it off instead of grinding it happen, and other synthetic resins can be used, which are in the cold or when Let stand solidify and through, the etching liquid, which dissolves the semiconductor, are not attacked.

The method according to the invention can also be used with semiconductor material other than germanium and in the manufacture of components other than diodes, for example for the manufacture of transistors be used.

Finally, chemical etching can be used instead of the electrolytic etching described will.

Claims (5)

Patent claims: 1. A method for producing electrical semiconductor components, characterized in that that a semiconductor body containing a pn junction and provided with electrodes is covered with insulating material that the insulating material is removed so that a part of the semiconductor body is exposed, and that then the semiconductor body next to and under a non-ohmic Electrode is etched away so that the area of the pn junction is reduced. 2. The method according to claim 1, characterized in that part of the semiconductor body is removed simultaneously with part of the coating so that the pn junction is partially exposed. 3. The method according to claim 1 or 2, characterized in that part of the coating by Grinding is removed. 4. The method according to any one of claims 1 to 3, characterized in that part of the Semiconductor body is removed by electrolytic etching. 5. The method according to any one of claims 1 to 4, characterized in that an epoxy resin is used as the coating material. Considered publications:
German Auslegeschrift No. 1 097 574;
French patents No. 1,217,793,
226 312; U.S. Patent No. 2,802,159. A priority document was displayed when the registration was announced. 1 sheet of drawings 609 503/297 1.66 © Bundesdruckerei Berlin