Whirl etching system and method for large area silicon chips

Abstract

The invention discloses a whirl etching system for large-area silicon chip and a method thereof, comprising an autorotation etch fixture, a revolution arm, an etch bath, a de-ionized water rinse bath, a bubbling agitating device, a condensing and temperature control device; the etch fixture is installed on the arm for uniform autorotation driven by a rotating motor; the etch bath contains chemical corrosive liquid; the bubbling agitating device is located at bottom of the bath; the condenser pipe and the temperature control thermoelectric couple are installed at side wall of the etch bath; the de-ionized water rinse bath is located adjacent to the etch bath; when etching the silicon chip, the arm drives autorotation fixture into dip into the chemical corrosive liquid in the etch bath, while the arm undergoes uniform revolution; after that, the autorotation fixture driven by the arm is dipped into the de-ionized water rinse bath for cleaning; controlling the temperature of the corrosive liquid, and mixing the corrosive liquid evenly by the agitating device, so as to ensure that the concentration, the temperature of the corrosive liquid is substantially uniform, and that etch speed on the surface of the silicon chip is consistent, so as to enhance uniformity of silicon chip etching.

Description

technical field [0001] The invention relates to the technical field of semiconductor manufacturing, in particular to a large-area silicon wafer spin etching system and method. Background technique [0002] With the continuous improvement of thyristor manufacturing technology, thyristors are developing in the direction of high voltage, high current and large area. Therefore, in the manufacturing process of thyristors, higher requirements are put forward for the flatness and uniformity of the single crystal silicon wafers used. [0003] At present, there are mainly two methods for the surface treatment of silicon wafers: mechanical grinding and chemical liquid corrosion. [0004] The mechanical grinding method puts the silicon wafer on the grinding disc, and after high-speed rotation, the silicon wafer and the grinding disc are rubbed to achieve the purpose of thinning and smoothing. The surface of the silicon wafer processed by this method is rough and uneven, thereby increa...

AI Technical Summary

Problems solved by technology

This method improves the temperature and concentration uniformity of the etching solution in the horizontal direction to a certain extent, but the concentration and temperature of the etching solution in the vertical direction have not been effectively mixed uniformly, and the etching speed of multiple silicon wafers in the same batch Inconsistent, the flatness of the obtained silicon wafers is also different, which affects the stability of device performance; in addition, the stirrer is located at the bottom of the etching tank and cannot fully stir the upper etching solution, which affects the uniformity of silicon wafer etching

Images