Method Of Providing Individual Bodies On A Basic Body

Abstract

A method of providing individual bodies on a basic body by firstly laying the individual bodies on a common support picking them up and transferring them, by means of a carrier member with an adhesive surface, to the basic body and holding them on the basic body until they are secured by suitable means such as glueing or soldering. Carrier members and support members are provided for carrying out the method.

Description

BACKGROUND OF THE INVENTION

The invention relates to a method for the simultaneous provision of a plurality of individual bodies on a common basic body.

In the semiconductor art in particular, the problem often arises of providing a relatively large number of semiconductor devices, that is to say semiconductor bodies provided with component structures as well as electrodes etc., separately from one another on a common base or basic body. This is necessary, for example in the production of switching circuits which comprise a relatively large number of components, when the semiconductor material used, such as compound semiconductors of the groups III-V and II-VI, does not permit the construction of a monolithic solid-state switching circuit with the structures of all the components in one semiconductor body, or when different semiconductor materials are to be used for the construction of such a switching circuit. Thus the manufacture of semiconductor devices in which a plurality of luminescence diodes of gallium-arsenide (GaAs) is used, the diodes being disposed side by side on a base, and which being used for the reading of punched tapes or as a solid-state display screen for the representation of figures and writing, involves enormous difficulties. For according to the methods hitherto usual, the diodes are laid individually by hand in the required relationship to one another on the base or basic body which is then covered, at its surface adapted for securing the diodes, with a layer of tin or another solder for example so that the diodes can be firmly soldered to this base by brief heating of the base to soldering temperature. This soldering process in turn involves difficulties in the known methods because when the solder melts the individual diodes begin to float on the molten solder and are displaced from their predetermined position. With this method, therefore, it is often necessary to push individual diodes into their correct position before the solder solidifies and in the course of this it is often impossible to prevent solder from being forced up between the diodes and short-circuiting their PN-junctions.

SUMMARY OF THE INVENTION

It is an object of the present invention to provide a method for the simultaneous provision of a plurality of individual bodies on a common basic body, which, in particular, also simplifies and decisively improves the securing of individual semiconductor components to a common basic body or base.

According to the invention, there is provided a method for the simultaneous provision of a plurality of individual bodies on a common basic body, comprising the steps of first laying said individual bodies on a common support, laying a carrier member with an adhesive surface over said bodies resting on the support and pressing it against said support in so that all said individual bodies adhere to said carrier member, removing said carrier member from said support with said individual bodies adhering thereto and arranging said carrier or said basic body so that said individual bodies to be secured rest with their surface remote from said carrier body on said basic body, and removing said carrier member from said basic body after the individual bodies have been secured.

BRIEF DESCRIPTION OF THE DRAWINGS

The invention will now be described in greater detail by way of example with reference to the accompanying drawings in which:

FIG. 1 is a perspective view of a support for positioning a plurality of semiconductor bodies;

FIG. 2 is a perspective view of a carrier member for transferring the semiconductor bodies from the support of FIG. 1 and,

FIG. 3 is a perspective view of the carrier member of FIG. 2 together with a base on which the semiconductor bodies are to be positioned and attached.

DESCRIPTION OF THE PREFERRED EMBODIMENT

Basically the invention proposes that during the simultaneous provision of a plurality of individual bodies on a basic body, these individual bodies should first be laid on a common support, that then a carrier member with an adhesive surface should be brought over these individual bodies lying on the support and be pressed against the support in such a manner that all the individual bodies cling to said carrier member. Then the carrier member with the individual bodies adhering thereto is removed from the support and placed on the basic body in such a manner that the individual bodies lie with their surface remote from the carrier member on the basic body for securing. After the individual dual bodies have been secured to the basic body, the carrier member is removed again according to the invention.

The advantage of the method according to the invention consists primarily in that all the individual bodies are applied to the basic body in a single operation and so the time-wasting, separate provision of the individual bodies is eliminated. In addition, with the method according to the invention, assurance is provided that the individual bodies are held by the carrier plate up to the moment when they are firmly bonded to the basic body and thus cannot be mutually displaced. With the method according to the invention, therefore, it is possible to determine the subsequent relationship of the individual bodies to one another on the basic body by their particular arrangement on the support, and in many cases this facilitates work considerably, particularly as the supports used can easily be equipped with auxiliary means which decisively simplify the necessary grouping of the individual bodies.

Provided that the individual bodies as well as the basic body used permit, the securing of the individual bodies to this basic body is preferably effected by means of a soldered connection although it would easily be possible, within the scope of the method according to the invention, to secure the individual bodies by glueing or other means. Thus when a plurality of semiconductor components are provided simultaneously on a common base, components and/or base are provided with a layer of solder and possibly also with a flux at the surface at which they are to be connected to one another. In the case of the semiconductor components at least, the provision of this layer of solder may most appropriately be effected directly during their manufacture. With the method according to the invention, the semiconductor components are then laid on the support so that they rest with their surface provided with solder on said support. The components are subsequently removed from the support by means of the carrier member, as described, and pressed against the base, which is heated to soldering temperature, until the solder has solidified after the cooling down of the base and a firm connection is established between base and component.

Particularly when the securing of the individual bodies to the basic body is effected by means of soldering, the carrier member may advantageously be provided with a flux which has adhesive properties such as rosin varnish or silicone oil, at least at that portion of its surface to which the individual bodies are to adhere. In this manner, the carrier member acquires the adhesive surface necessary for carrying out the method according to the invention or adhesive properties of the carrier member which may already have been caused by other substances are at least reinforced while at the same time assurance is provided that a sufficient quantity of flux will be present for the soldering operation.

A carrier member which consists of silicone rubber, at least at the surface at which the individual bodies are to adhere, is particularly suitable for carrying out the method according to the invention. As a result of the use of this rubber, the carrier member already has the adhesive surface necessary for carrying out the method according to the invention without a coating of the above-mentioned adhesive flux or another adhesive substance.

The carrier member which is preferably plane at its surface adapted to receive the individual bodies, as is the support, may be mounted, for example, on the carrying arm of a micromanipulator, so as to simplify in this manner the provision of very small individual bodies on basic bodies having only small dimensions, as for example the provision of a plurality of semiconductor components on a common base.

The arrangement of the individual bodies on the support can be rationalized by providing the support with a plurality of recesses. The individual bodies are then inserted in these recesses and are thus automatically in the required position in relation to one another, predetermined by the arrangement of the recesses. Furthermore, when such a support provided with recesses is used, there is also the possibility of placing a large number of individual bodies initially at random on the support and then occupying each of these recesses, the lateral dimensions of which match the individual bodies, with such a body by shaking and/or holding said support inclined, and removing the individual bodies which are not accommodated in recesses from the support.

The recesses, which are preferably arranged in the form of a grid, are naturally so constructed that all the individual bodies accommodated therein project from the recesses with their surface remote from the support.

Such a support with recesses arranged in the form of a grid can easily be realised by placing a grating made of metal for example or a wire netting on as plane a surface as possible, in which case the meshes of this grating or netting form recesses to receive the individual bodies.

Referring now to the drawings, FIG. 1 shows a support 1 on the surface of which there are provided several cell-like recesses 2. The edges of the recesses are formed by a grating 3 for example a metal grating which is laid on the plane surface of the support 1 and secured there. As the Figure shows, the sizes of the openings in the grating or meshes forming the recesses are selected so large that one flat individual body 4, for example a semiconductor component, just fits into each of the recesses arranged in the form of a grid. The thickness of the grating is less than the height of the bodies 4 so that these bodies project from the recesses with their surface remote from the support 1.

FIG. 2 shows a carrier member 5 for transferring the individual bodies 4 from the support to the basic body or base. This carrier member comprises a handle 6 on its upper side, in the manner of a stamp, to improve manipulation. The carrier member consists, at least at its plane face 7, of silicone rubber which imparts adhesive characteristics to this face so that the individual bodies resting on this support remain suspended, as illustrated in FIG. 2, after the carrier member has been pressed against the support. The adhesive properties of the carrier member can, of course, likewise be improved here by providing at least the face 7 of the carrier member with a flux having adhesive properties before it is used.

FIG. 3 shows the carrier member 5 and a housing base 8 on which the semiconductor components 4 adhering to the carrier member are to be secured by means of a soldered connection. The base 8, which comprises a plurality of electrode leads 9, lies on a heating plate 10. The electrode leads 9 project, then, through bones provided in this heating plate specially for this purpose. In order to secure the semiconductor components 4 to the base 8, this is first heated to soldering temperature by means of the heating plate and then the carrier member with the components is pressed against the base. Base and/or semiconductor components are provided with solder and flux, as described above, so that after the heating plate 10 has cooled down, for example by switching off a heating current heating said plate, the components are secured to the base 8 in the predetermined position.

FIGS. 1 to 3 naturally only give a diagrammatic illustration of the means to be used advantageously in carrying out the method according to the invention. As a result of the teaching of the invention, however, it is easily possible to adapt the carrier member in its specific construction, to each particular application in an optimum manner in the sense of the invention.

Claims

What I claim as new and desire to secure by Letters Patent of the United States is:

1. A method for simultaneously securing a plurality of individual bodies, each of which has a layer of solder and flux on one surface thereof, to a common basic body, comprising the steps of:

a. placing said individual bodies on a common support member with the layers of solder and flux resting on said common support member;

b. laying a carrier member with an adhesive surface over said individual bodies resting on said common support member and pressing said adhesive surface against the surfaces of said individual bodies which are opposite to the layers of solder and flux so that all said individual bodies adhere to said adhesive surface of said carrier member;

c. removing said carrier member from over said common support member with said individual bodies adhering thereto;

d. arranging said carrier member over said common basic body;

e. pressing the layers of solder and flux of said individual bodies against said common basic body by means of said carrier member;

f. heating said common basic body briefly to the soldering temperature and continuing the pressure of said individual bodies against said common basic body until solidification of said solder and the resultant establishment of a connection between said common basic body and said individual bodies; and

g. removing said carrier member from said individual bodies after the individual bodies have been secured to said common basic body.

2. A method as defined in claim 1, further comprising grouping said individual bodies on said support in the relationship to one another which they are subsequently to assume on said basic body before laying said carrier member therein.

3. A method as defined in claim 1, further comprising providing said carrier member with a flux with adhesive characteristics at least at that portion of its surface at which the individual bodies are to adhere.

4. A method as defined in claim 1, wherein said flux for said carrier member is selected from rosin varnish and silicone oil.

5. A method as defined in claim 1, wherein said flux for said carrier is a mixture of resin varnish and silicone oil.