Ultrathin single crystal germanium wafer processing method

Abstract

The invention discloses an ultrathin single crystal germanium wafer processing method. The ultrathin single crystal germanium wafer processing method is characterized by comprising the following steps: first, using wire-electrode cutting equipment to cut a single crystal germanium rod to obtain single crystal germanium wafers with the thickness being less than 0.5mm; second, clamping the single crystal germanium wafers on a low-temperature polishing machine; third, firstly using a hard abrasive material with the Mohs hardness being greater than 9, such as diamond, corundum, silicon carbide, boron carbide with the granularity of 10-28[mu]m to froze and solidify an abrasive material polishing disk to serve as a polishing head for rough machining, and taking an anhydrous organic solvent as polishing liquid; using an abrasive material with the Mohs hardness being smaller than 9, such as CeO2 and silica with the granularity of 0.06-2[mu]m to froze and solidify the abrasive material polishing disk to serve as a polishing head for fine machining, and carrying out secondary processing, wherein the polishing temperature is controlled to be within minus 30DEG C to minus 10DEG C, the polishing pressure is controlled to be within 100-500g / cm<2>, the polishing solution is the anhydrous organic solvent, the flow rate is 50-500ml / min, the polishing rotation speed is 10-300r / min, and finally the ultrathin germanium wafers with the thickness being less than 0.15mm are obtained. The ultrathin single crystal germanium wafer processing method is simple and the yield is high.

Description

technical field [0001] The invention relates to a precision processing technology, especially a processing technology for ultra-thin single-crystal germanium slices, specifically a processing method for obtaining ultra-thin germanium slices by using frozen solidified abrasives to polish single-crystal germanium slices . Background technique [0002] At present, as the substrate material of compound solar cells, ultra-thin single-crystal germanium wafers need to be epitaxially grown by MOCVD on them. Therefore, there are not only very strict requirements on the surface quality, but also the thickness should be less than 0.2mm. Germanium is the most important semiconductor material after silicon. In addition to the semiconductor industry, germanium is widely used in aerospace industry, high-frequency ultra-high-frequency electronics, optical fiber communication, infrared optics, electronic devices, solar cells, chemical catalysts, biomedicine and other fields, and is a ve...

AI Technical Summary

Problems solved by technology

[0005] The purpose of the present invention is to solve the problems of fragility, easy deformation, uneven thickness, difficult control of parallelism and only small-area ultra-thin single crystal germanium wafers in the processing of ultra-thin single crystal germanium wafers, and to provide a method that can To achieve the purpose of rapid and uniform thinning of germanium wafers, and at the same time obtain ultra-thin single crystal germanium wafers with good flatness and small surface damage.