Patterned substrate, manufacturing method thereof and method for manufacturing epitaxial film from patterned substrate

Abstract

The invention provides a patterned substrate, a manufacturing method thereof and a method for manufacturing an epitaxial film from the patterned substrate. The manufacturing method of the patterned substrate includes the steps of 1), providing a Si substrate and making a plurality of pits in the surface of the Si substrate; 2), forming an AlN film on the surface of the Si substrate to fill the pits with the AlN film; 3), thinning the AlN film obtained in the step 2) so as to obtain the patterned substrate. The patterned substrate has the advantages that the large-sized Si-based AlN compound patterned substrate is obtained and the high-quality GaN epitaxial film is manufactured from the patterned substrate, so that the difficulty that the large-sized Si substrate in an epitaxial warping control process is lowered greatly, and epitaxial growth uniformity and repeatability are improved substantially.

Description

technical field [0001] The invention relates to the field of semiconductor materials, in particular to a patterned substrate, a manufacturing method thereof, and a method of manufacturing an epitaxial film using the patterned substrate. Background technique [0002] As a third-generation semiconductor material, GaN has been widely used in the production of optoelectronic devices due to its wide direct bandgap (3.4eV), high thermal conductivity, and high electron saturation drift velocity. Blue light, green light, and ultraviolet light diode (LED) devices; in terms of microwave power devices, due to the large polarized electric field at the interface of the AlGaN / GaN heterostructure, a high concentration of two-dimensional electron gas (2DGE) can be generated. And the electron mobility is also very high. Taking advantage of this characteristic, GaN materials are also widely used in microwave power devices. Since Si-based semiconductor technology has been developed for more t...

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Problems solved by technology

However, there is a 20.4% lattice mismatch and a 56% thermal mismatch between the Si substrate and the GaN material, resulting in a large tensile stress in the GaN epitaxial film after growth, and the grown GaN film is prone to cracking, which seriously affects the subsequent Fabrication and performance of devices; AlN / AlGaN buffer layer is generally used to pre-set a compressive stress layer between Si substrate and GaN epitaxial film to offset the tensile stress generated after cooling and obtain high-quality epitaxial film

However, as the size of the Si substrate increases, especially when it comes to the epitaxy of a 6-12 inch Si substrate, the warpage of the Si substrate is more difficult to control; the growth conditions are also very demanding, especially the growth temperature and airflow uniformity and other requirements are more stringent

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