Method for preparing direct band-gap germanium thin film

Abstract

The invention relates to a method for preparing a direct band-gap germanium thin film. The method comprises a GeOI substrate. A top layer germanium nanometer thin film is carried out a graphical processing, and a plurality of corrosion windows communicated with a bottom buried oxide layer is open. The buried oxide layer is carried out a wet etching until the buried oxide layer is thoroughly corroded so that the graphical top layer germanium nanometer thin film and a silicon substrate are virtually contacted. A polydimethylsiloxane (PDMS) carrier is provided and the PDMS carrier is closely connected with the top layer germanium nanometer thin film, so that the top layer germanium nanometer thin film virtually connected with the silicon substrate is transferred to the PDMS. Both ends of the PDMS carrier is clamped and carried out a reverse mechanical stretching so that the top layer germanium nanometer thin film can carry out deformation with the stretching of the polydimethylsiloxane carrier and produce a tensile strain inside. The strain size of the direct band-gap germanium thin film prepared with this method is controllable and can be used for a photoelectric device. The direct band-gap germanium thin film has the advantages of being small in defects and low in dislocation density. The method and technology for the direct band-gap germanium thin film prepared by the mechanical stretching is simple, and the cost is low.

Description

technical field [0001] The invention belongs to the technical field of semiconductors, and in particular relates to a method for preparing a direct bandgap Ge thin film. Background technique [0002] The rapid development of microelectronics technology makes Moore's law approaching its physical limit and is challenged. The rapid development of silicon-based optoelectronics in recent years is considered to be able to effectively extend the extension of Moore's law. At present, the main obstacle hindering the development of silicon-based optoelectronic integration technology is how to solve the problem of on-chip light source compatible with the existing silicon-based CMOS. Therefore, finding an effective active light-emitting material that is compatible with the silicon process is an important part of silicon-based optoelectronic integration. [0003] When the tensile strain in the Ge thin film is greater than 2.0%, the original indirect bandgap material can be transformed i...

AI Technical Summary

Problems solved by technology

[0005] In view of the shortcomings of the prior art described above, the object of the present invention is to provide a method for preparing a direct bandgap Ge thin film, which is used to solve the problem of high dislocation density and high cost of preparing a tensile strain Ge thin film in the prior art

Images