DE1237942B - Device for holding disc-shaped workpieces made of semiconductor material by suction - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

Number:
File number:
Registration date:
Display day:

B28d

German class: 8Od- 2

1237942
S80487Ib / 80d
July 19, 1962
March 30, 1967

The invention relates to a device for holding disc-shaped workpieces made of semiconductor material by suction on a flat one provided with openings for the passage of air fixed edition.

Crystals made of semiconductor materials, in particular single crystals, fall for most of the display high-purity or doped semiconductor material common processes as a rod-shaped body. These bodies are then sawn or split into slices for further treatment. The received In turn, wafers are subdivided into sections that correspond to the size of the semiconductor components to be manufactured. In the case of the series Production of semiconductor components, it is often expedient to use a large part of the To carry out the steps serving to manufacture the components on such a flat semiconductor body and the separation of this flat semiconductor body into those corresponding to the individual components Postpone pieces if possible. The reason for this is mainly that larger semiconductor wafers for a number of manufacturing processes much more manageable than the tiny semiconductor pieces which form the semiconductor body of modern semiconductor components.

In this way, the steps of prediffusion required in the manufacture of mesa transistors, the vapor deposition of pairs of electrodes and the alloying on a larger semiconductor wafer from 1 to 2 cm in diameter can be carried out much more precisely and easily than with one Semiconductor piece is the case, the largest diameter of which is 1 to 2 mm. About the semiconductor material to be able to better exploit, z. B. on a semiconductor wafer with a diameter of 1 to 2 cm, Depending on the size of the components to be produced, a more or less large number of electrode pairs vapor-deposited and alloyed using known methods. Only then are the semiconductor wafers in a number of equal pieces, each with a pair of electrodes, and the individual pieces by soldering on a metallic plate, in particular serving as a housing part at the same time, with the required third electrode provided. In this way one achieves a considerable facilitation of the production as well as a considerably lower spread of the electrical properties of the transistors obtained.

However, in order not to lose the advantage mentioned again by the fact that when the semiconductor wafers are broken up due to damage to the halving device for holding the wafers
Workpieces made of semiconductor material
Suction

Applicant:

Siemens Aktiengesellschaft, Berlin and Munich, Munich 2, Wittelsbacherplatz 2

Named as inventor:

Dipl.-Phys. Winfried Meer, Munich

Conductor material undesirable losses occur, is a careful work when dividing the Semiconductor wafers necessary. It is useful to use the z. B. usual when cutting glass Breaking technique after marking the intended break point by scoring Has. Since the slices to be cut are generally very thin, i. H. a strength of the order of magnitude some 100 μ, ζ. B. from 150 to 250 μ, is a clamping during the scratching very dangerous. In order to still be able to maintain the dimensional accuracy required for the scoring, has one helped oneself by the fact that one the flat semiconductor wafers on one in particular made of glass Existing, cleaned, level surface puttied on with Canada balm and then that to the desired Division leading system of lines scratched on the semiconductor wafer. After the scoring has been completed The glass underlay with the adhering semiconductor wafer was then placed in a Canada balm dissolving, z. B. brought from trichlorethylene existing liquid, which at the same time by ultrasonic vibrations was stimulated. With a corresponding intensity of the ultrasonic vibrations, the Semiconductor wafer detached from the glass in the liquid bath broken along the incised lines.

In addition to the known suction pipettes for the transport of workpieces, the state of the art refer to the so-called vacuum tensioning devices for semiconductor purposes, at which the workpiece is on a conveyor or

709 547/10

Claims (5)

3 4 is recorded on a working document. When creating arbitrarily curved incised lines in the heating of semiconductor wafers, one has to take advantage of semiconductor wafers,
helped to cut and cut the half The technique of scratching is well known. To glue the instruction disc to a work surface. The pressure applied by the diamond tip must of course. There is easily the possibility of avoiding the brittleness of both the diamond and the sticking and taking the workpiece into account by means of the semiconductor material. The pneumatic workpiece holder, which is known for its purpose, is to be adjusted in such a way that the lines have a depth of tern. The known devices consist of about Va to 1 μ obtained. a vacuum chamber, which on its top with The advantages of the method according to the invention a perforated plate is completed. The main thing about the io is that it's easy to do perforated plate, the workpiece is also thinner and therefore mechanically to lie in the processing. With such a front sensitive semiconductor wafers or similar direction one is able to achieve a minimum hole spacing and licher flat bodies that are required for the scoring. tied a maximum hole size. This makes such a holder in a simple and convenient way to ensure the evenness of the suction or the uniformity or after the end of the scoring in the moderate pressure on the substrate, which can be solved for a moment. the scratching is of particular importance, the scratched panes can be made by ultra- not guaranteed. It is the object of the invention to measure the effects of sound along the incised lines 2 * to achieve an improvement here and to set up a facility, whereby one expediently to create a device with which it is possible to convert the work- shop into one that oscillates at an ultrasonic frequency pieces evenly and in far more places to liquid, which against the material of the discs hold than this is inert with the known suction devices. With enough energy the can be possible. Ultrasonic vibrations break up the cockroaches To achieve this object, according to the invention, basically along the incised lines. Did on- suggested that the support made of porous work- 25 facing ultrasonic power is directed fl & eh the substance is made. Thickness of the slices. With regard to an expedient implementation, the fragments of the FIG. 1 pointed out. A space formed by a sub-divided semiconductor wafer in a completely disorderly pressure vessel 1 is due to a porous, wet state at the bottom of the applied liquid hard layer 2 with a flat-ground surface (outdoor bath. In most cases, however, it is zw & ekfläche) completed. Layer 2 consists e.g. B. from moderate, if the pieces obtained without re-sintered glass or quartz powder, in particular orientation, as it is often necessary, üitt Ait a glass frit. When the semiconductor pieces are actuated to bring the semiconductor pieces to the position required for the vacuum process connected to the vacuum vessel connected to the socket 1 ', air is sucked through the layer 2 from the pump 3 (e.g. a water jet pump), which serves to break the semiconductor wafer . One can refer to the layer 2 device. When the semiconductor wafer 4 is used, this is also attracted to the porous layer 2 in the device according to the invention, for example. The configuration achieved in this way according to FIG. 2 possible.
A vacuum vessel 31 is used by the pump or by means of a corresponding 40, which via an evacuation support 31 'reduces the area of the porous glass layer 2 that is not covered by the semiconductor wafer, e.g. a water jet' pump, is connected. In a similar way, wi * further are set so that the semiconductor, the vacuum vessel in the device according to plate 4 by the me- F i g. 1, the vacuum vessel in this case is not moved out of its position by mechanical forces 45 with a porous solid layer 32, e.g. B. a Gl & s * can be. frit, covered. There is a waved on the glass frit, The scratching is carried out by means of a diamond tip, preferably likewise porous intermediate layer 33, i> B. whereby it is advisable to place a soft cloth or a layer of foam rubber on the disc with appropriate pressure during the scratching. On this the H & lb-disc to be broken is to move the pressed diamond tip, because 50 plate washer 34 is placed, which in turn can be easily adjusted by ftindr in this case, the gas device of the cross table, which is made of elastic, soft material, is covered by the film 35, which is leakproof for monitoring is. If one uses the microscope used for the scoring on the wall of the vacuum vessel 31 with the film 35 in carrying out the scoring. For this purpose, the required dimensions are gas-tight, e.g. B. The vacuum vessel 1 is fastened to the cross-clamping device 36 via eiöfc, connected, operated at the operating table of the microscope and pressed against the vacuum vessel 34 in the manner described in the evacuation process the porous soft layer 33 presses the suctioned semiconductor wafer from below against the stationary, the porous layer 32 having a diamond tip held for breaking. A suitable fixed base of the adjusting device of the cross table provides a controlled δο position by breaking with a steel roller.
Movements becomes the diamond tip and at the same time PatentarKiwVhp
also the field of vision of the half-ratemansprucne to be scratched.
Leather surface sharply set microscope over 1. Device for holding disk-shaped the surface of the semiconductor wafer under production workpieces made of semiconductor material by anging and simultaneous control of the desired 65 suction on a flat, with openings for the incised lines. There is no passage of air provided firm © support, difficulties, the adjusting screws of the cross - characterized in that the table is made of porous material not only to produce straight, but layered material. 2. Apparatus according to claim 1, characterized in that the support surface is planar is ground. 3. Apparatus according to claim 1, characterized in that the support is a glass frit. 4. Use of an arrangement according to one of claims 1 to 3 when scratching and / or Breaking semiconductor wafers. Considered publications: German Patent Nos. 836401, 526249; U.S. Patent Nos. 3,040489, 2970730, 2198765; "Technica", 1957, No. 11, pp. 623 to 626; "Radio technology", 1961, no. 5, pp. 45 and 46; Bergmann: "The Ultrasound", Stuttgart 1954, Verlag S. Hirzel, 6th edition, p. 565. 1 sheet of drawings