Light-emitting diode (LED) epitaxial wafer growing on Si patterned substrate and preparation process of LED epitaxial wafer

Abstract

The invention discloses a light-emitting diode (LED) epitaxial wafer growing on an Si patterned substrate and a preparation process of the LED epitaxial wafer. The preparation process includes the following steps of using the Si patterned substrate and selecting a crystal face (111) as a crystal orientation, wherein a plurality of pattern projections with the same shapes are distributed on the crystal face (111); subsequently, sequentially growing an AlN buffer layer, an AlGaN step buffer layer, an u-GaN layer, an n-GaN layer, an InGaN/GaN quantum well layer and a p-GaN layer on the Si patterned substrate; finally, manufacturing a cavity in the top of each pattern projection. According to the LED epitaxial wafer growing on the Si patterned substrate and the preparation process of the LED epitaxial wafer, Si is used as the substrate, meanwhile, horizontal epitaxial growth of a thin film is promoted by combining the pattern substrate and the cavities, crystal qualities are improved, the stress condition is effectively relieved so as to solve the crack problem and avoid difficulties of light absorption of the Si patterned substrate, and the obtained LED epitaxial wafer is good in photoelectric property, high in crystalline quality, and applicable to LED devices.

Description

technical field [0001] The invention relates to an LED epitaxial wafer, in particular to an LED epitaxial wafer grown on a Si pattern substrate and a preparation method thereof. Background technique [0002] LED is a product under the social background of advocating energy saving and emission reduction. It has good environmental protection, energy saving and anti-seismic performance, and has broad prospects in the future lighting market. It is known as the fourth-generation green lighting source. [0003] As one of the representatives of the third-generation semiconductor materials, GaN has excellent properties such as direct band gap, wide band gap, high saturation electron drift velocity, high breakdown electric field, and high thermal conductivity, and has attracted extensive attention in microelectronic applications. Since I. Akasaki successfully obtained p-GaN for the first time and achieved a new breakthrough in blue LEDs, GaN-based compounds have been the main materia...

AI Technical Summary

Problems solved by technology

However, the quality of GaN single crystal thin films prepared on Si patterned substrates is not as good as that of sapphire substrates, mainly due to: the thermal mismatch between Si and GaN is much higher than that of sapphire, which makes epitaxial wafers more prone to cracking; N is easy to form amorphous SixNy at the interface, which affects the growth quality of GaN; the absorption of visible light by Si will also greatly reduce the luminous efficiency of LED

Images