A method for directly epitaxially growing germanium dummy substrate on silicon substrate

Abstract

The invention discloses a method for directly epitaxially growing a germanium virtual substrate on a silicon substrate. 1, obtain a silicon substrate of a (100) crystal plane or a silicon substrate ofa (111) crystal plane; 2, aft that silicon substrate is treated with hydrofluoric acid, carry out surface treatment in a vacuum environment; 3, growing a layer of silicon buffer layer on the processed silicon substrate through a molecular beam epitaxy method; Step 4, adjusting to the appropriate growth temperature, and then directly epitaxially growing a germanium virtual substrate with a thickness of micron on the silicon buffer layer. The method of the invention can directly epitaxy the germanium virtual substrate on the silicon wafer, the surface of the germanium virtual substrate grown bythe method is flat, the quality of the single crystal is high, the crystal lattice can be relaxed completely, and the germanium virtual substrate can be used for the growth of subsequent materials instead of the germanium substrate. The method does not need to adopt the layer-by-layer growth mode of gradually increasing the germanium content, and the preparation process is simpler and the cost can be reduced.

Description

technical field [0001] The invention relates to a method for directly epitaxially growing a dummy germanium substrate on a silicon substrate, more specifically, it relates to the optimization of the growth conditions of a dummy substrate of high-quality germanium directly epitaxially grown on a silicon substrate, including the processing of the substrate , the growth of the buffer layer and the optimization process of the growth temperature of the germanium virtual substrate. Background technique [0002] Silicon (Si) and germanium (Ge) are the most common semiconductor materials and are also important materials for electronic components. Silicon-based germanium epitaxial material can be used as a new material for silicon-based high-speed circuit research, and it is the first choice material for silicon-based long-wavelength photodetectors. [0003] In addition, germanium matches the lattice of GaAs materials, and silicon-based germanium epitaxial materials can be used as v...

AI Technical Summary

Problems solved by technology

[0005] 1) The surface roughness of the Ge epitaxial layer is large, which is not conducive to the growth of III-V heterostructures on the subsequent Ge buffer layer;

[0006] 2) The high dislocation density of the Ge epitaxial layer degrades the performance of the device when it is applied in optoelectronic devices

This method is complicated to operate and needs to constantly change the ratio of germanium to silicon, which not only wastes time but also costs a lot

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