A silicon wafer edge processing technology for gallium nitride epitaxy

Abstract

The invention discloses a silicon chip edge processing technology for gallium nitride epitaxy. After slicing the silicon single crystal, use a 1000-mesh grinding wheel to perform the first rough chamfering to remove the damage of the edge slicing process, and then perform grinding and etching, so that the silicon wafer has a better edge quality; the surface is protected by back-sealing silicon dioxide , to avoid the surface damage and contamination caused by the suction cup and the grinding wheel during the second chamfering, and at the same time the high temperature process also releases the stress on the edge; use a 2000 mesh grinding wheel for the second fine chamfering, so that the chamfering surface can reach the maximum and With a finer surface, the surface damage and edge stress are removed by light corrosion with 50% potassium hydroxide solution, and the best chamfer edge quality is obtained. The invention is simple and easy to implement, and can effectively improve the quality of the chamfered edge area 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