Silicon wafer edge processing technology for gallium nitride epitaxy

Abstract

The invention discloses a silicon wafer edge processing technology for a gallium nitride epitaxy. The silicon wafer edge processing technology comprises the steps of slicing silicon single crystal, carrying out the first rough chamfering through a 1000-mesh grinding wheel to remove damages caused by edge slicing, then carrying out grinding and corrosion to enable the silicon wafer to have good edge quality; protecting the surface by back-sealing silicon dioxide, avoiding surface damages and contamination caused by a sucker and a grinding wheel during the second chamfering, and also releasing the edge stress during the high temperature process at the same time; and carrying out the second precise chamfering by adopting a 2000-mesh grinding wheel so as to maximize the chamfering area and have a finer surface, carrying out light corrosion through a 50% potassium hydroxide solution to remove the surface damages and edge stress and obtain the best chamfering edge quality. The silicon waferedge processing technology is simple and easy to implement, and can effectively improve the quality of a chamfering edge region of the silicon single crystal polished wafer.

Description

technical field [0001] The invention relates to semiconductor material processing technology, in particular to a silicon wafer edge processing technology for gallium nitride epitaxy. Background technique [0002] Gallium nitride has the characteristics of high saturation electron velocity, breakdown voltage and high temperature resistance, and can be used to make high-temperature, high-frequency and high-power electronic devices (FET, HEMT) that operate in extremely harsh environments, and are used in wireless communications (wirelessstation), satellites communications and other fields. Especially in the past ten years, the development of wide bandgap semiconductor materials and devices represented by GaN has been very rapid and has greatly promoted the development and application of information science and technology. Therefore, the preparation of GaN epitaxial materials and devices has become a hot research topic at present. Domestic research institutions and universities...

AI Technical Summary

Problems solved by technology

Generally, chamfering is processed by rough chamfering of 800# grinding wheel + fine chamfering of 1500# grinding wheel. After chamfering, it needs to be ground with a removal amount of 50-60 μm. The impact of the edge during grinding will cause new damage to the chamfered edge. When chemical etching is carried out again, since the chamfered edge area is a combination of multiple crystal orientations, the consistency of the corrosion rate is poor, which is likely to cause the mechanical damage of the edge to enlarge, and the edge chamfering profile becomes sharp , and further reduces the surface width, which in turn makes the quality of the edge area worse after polishing

After high-temperature epitaxy of gallium nitride, due to serious lattice mismatch and difficult stress relief, serious slip lines and even cracks