SU343324A1 - Device for securing semiconductor substrates - Google Patents

Abstract

A DEVICE FOR FASTENING SEMICONDUCTOR SUBSTRATES ^ heated by electric current, during creeping epitaxial layers, containing spring, clamp clamps and current leads, in order to improve the quality of epitaxial) E1YH layers, currentgrowing, in order to improve the quality of epitaxial) E1YX layers, current-conducting, to a current-forming, to a current. in the form of two pairs of metal plates with contact bars made of semiconductor substrate material.

Description

The invention relates to technological equipment of electronic equipment, in particular, to installations for the preparation of epitaxial layers.

. A necessary condition for obtaining semiconductor layers with a perfect crystal structure and controlled electrical parameters is the absence of contamination of the layers in the process of their latching. Uncontrolled impurities remove the specific resistance, the lifetime and mobility of charge carriers, increase the density of defects of the crystal structure in the layers, and impair the properties of devices made on their basis.

 The most likely source of contamination of the layers is the heated parts of the working chamber of the installation. One of the methods that gives the least pollution is by heating semiconductor substrates with an electric current passing directly through them. This method is used, for example, to obtain silicon layers by vacuum evaporation. Typically, in such cases, the voltage to the silicon substrates is applied using plates and paper clips from tungsten, molybdenum or tantalum.

The disadvantage of the used structures of current-carrying substrate holders is the high temperature of metal-silicon contacts. For example, at a temperature of silicon substrate 1380 With dimensions of 60x5x1 mm, water-cooled molybdenum - pyastine 0.2 mm thick, supplying voltage to silicon, are heated up to 900-1200 s. In places of metal contact with silicon, which usually has a small area of 1 mm; local heating, sparking, and destruction of the contact are observed. In this case, it is possible to contaminate the growing layers.

The purpose of the invention is to improve the quality of dipaxial layers. This is achieved by the fact that the current leads of the fixing device are made in the form of two pairs of metal plastics with contact bars made of semiconductor substrate material. 334 The drawing shows the proposed device. The ends of the heated semiconductor substrate 1 are placed between two pairs of bars 2 and 3 of silicon. Using metal 4, the current-carrying metal plates 5 and 6 clamp the ends of the bars. Tokopodvod Shche plate connected to a source of electric current. Bars are made of low-resistance, degenerate silicon. This is due to the fact that as the resistivity of a semiconductor decreases, so does the resistance of its contact area with MeTaiPioM. The dimensions of the bars are chosen such that the heating of metal current-carrying plates due to heat generation on the bars themselves and by heat conduction from the substrate is the smallest, so when the silicon sample is heated to 1400 ° C, the contacts are heated to. The temperature gradient in the substrate from the ends to the center is not more than 5 ° C / cm. The use of the proposed device makes it possible to reduce the substrate temperature when obtaining perfect layers (the dislocation density and packing defects are 10 cfm instead, and the lowest epitaxial growth temperature is up to 430 s.

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Claims (1)

A DEVICE FOR FASTENING SEMICONDUCTOR SUBSURES ₎ heated by electric current, when receiving epitaxial layers, containing spring clips and current leads, so as to improve the quality of epitaxial layers, the current leads are made in the form of two pairs of metal plates with contact bars made by from semiconductor substrate material.