Process improvement method based on quartz glass epitaxial GaN

Abstract

The invention provides a process improvement method based on quartz glass epitaxial GaN. Slurry made of different materials and a grinding disc are used for thinning the quartz glass for multiple times to prepare a wafer structure with the preset thickness smaller than 70 microns and the preset thickness uniformity TTV of + / -0.5 microns, the thickness uniformity reaches the nanoscale, the risk that the wafer structure is broken easily due to the fact that quartz glass is fragile in mechanical performance is avoided, and the integrity of a front circuit of the wafer structure can be guaranteed.Moreover, the quartz glass subjected to multiple times of thinning is polished, so that the surface roughness is smaller than a preset threshold value, for example, the surface roughness Ra is smaller than 1nm, the electroplating compactness of a heat dissipation metal layer is greatly improved, the adhesive force of the heat dissipation metal layer is greatly enhanced, and the heat dissipation capacity of the wafer structure during working is effectively improved.

Description

technical field [0001] The invention relates to the technical field of semiconductors, in particular to a process improvement method based on quartz glass epitaxy GaN. Background technique [0002] Gallium nitride (GaN) is a wide bandgap semiconductor material, which has a large bandgap (3.4eV), a high breakdown voltage (3.3MV / cm), and a high two-dimensional electron gas concentration (greater than 10 13 cm 2 ), high velocity of saturated electrons (2.8×10 7 cm / s) and other advantages have received widespread attention internationally. [0003] At present, the high frequency, high voltage, high temperature and high power characteristics of AlGaN / GaN HEMT devices (high electron mobility transistors) make them have great prospects in microwave power devices. [0004] However, the heat dissipation and grounding problems of high-power devices have been plagued by the practical and industrialization of AlGaN / GaN HEMT devices. Among them, the large-area heat-dissipating metal ...

AI Technical Summary

Problems solved by technology

[0004] However, the heat dissipation and grounding problems of high-power devices have been plagued by the practical and industrialization of AlGaN / GaN HEMT devices

[0005] Common GaN epitaxial structures mostly use sapphire or silicon carbide materials as substrates, because silicon carbide and sapphire materials have the advantages of high lattice matching as substrates for growing GaN epitaxial structures, which also causes the price of epitaxial substrates to remain high. question

[0006] If quartz glass is used as the substrate material, it has the advantage of low price, but due to the fragile mechanical properties of quartz glass, it is easy to disintegrate when it is thinned to a certain thickness, and the roughness Ra of the surface of quartz glass is not good, resulting in heat dissipation metal Poor adhesion, easy to fall off

Images