A method for making IV-VI sector semiconductor single crystal film on CdZnTe underlay

Abstract

The invention provides a method for preparing an IV-VI semiconductor single crystal thin film on a CdZnTe substrate, wherein, in a molecular beam epitaxy(MBE) device, by adopting an MBE growth method and utilizing molecular beam sources of different IV-VI compounds and under different growth temperatures(200 to 425DEG C), the single crystal thin film is epitaxially grown on the CdZnTe single crystal substrate materials; the CdZnTe substrate has a general formula of Cd1-xZnxTe, wherein X is equal to 0 to 0.3; the single crystal thin film grows by the vertical Bridgman method or vapor transport method, is cut along the (111) crystal orientation or (100) crystal orientation, is mechanically polished by Al2O3 powder and then is chemically polished by the bromine-methanol, the concentration of which is 1 percent. The method for preparing an IV-VI semiconductor single crystal thin film on a CdZnTe substrate has the advantages of being capable of realizing the controllable growth of device structures such as hetero junction, quantum well and superlattice, etc.

Description

technical field [0001] The invention belongs to the technical field of epitaxial preparation of semiconductor single crystal thin films and heterostructures thereof, and specifically relates to CdZnTe (or called Cd 1-x Zn x Te: X=0~0.3) A method for preparing a IV-VI group semiconductor single crystal thin film on a substrate. Background technique [0002] In recent years, optoelectronic devices such as mid-infrared lasers and mid-infrared detectors developed by IV-VI semiconductors (PbTe, PbSe, etc.) have application prospects in important fields such as environmental detection, toxic gas monitoring, biomedicine, and national defense. Group VI semiconductor materials have become a research hotspot. Group IV-VI semiconductor materials include binary system PbSe, PbTe, SnSe, SnTe and ternary system PbSrSe, PbSrTe, PbSnSe, PbSnTe, PbEuSe, PbMnTe and their heterostructures, etc. IV-VI group semiconductor materials are It is a narrow bandgap semiconductor material with unique...

AI Technical Summary

Problems solved by technology

But defects caused by lattice mismatch and thermal mismatch between PbTe and GaAs still become obstacles to further improve device performance

Moreover, GaAs belongs to the III-V group materials, the desorption process on the GaAs surface has very high requirements on the vacuum chamber, and the epitaxial growth of the CdTe buffer layer increases the complexity of device fabrication and increases the cost of IV-VI semiconductor device applications.

And epitaxial CdTe on GaAs substrate requires low temperature deposition, which will affect the crystal quality of CdTe buffer layer

[0005] Chinese patents 200710068039.7 and 200710068863.2 provide methods and devices for preparing IV-VI semiconductor single crystal thin films and heterostructures, and obtain high-quality single crystal thin films, but the substrate material used is BaF 2 (111) single crystal, Si(111) single crystal covered with CaF 2 、BaF 2 Buffer layer, MgO(100), MgO(111) single crystal substrate, the above substrates are all insulators, in these CaF 2 、BaF 2 , the growth of IV-VI semiconductor single crystal thin films on the MgO insulator substrate will bring a lot of inconvenience to the post-process manufacturing of electronic devices, and the heat dissipation characteristics are poor, which will reduce the performance of the device and increase the manufacturing cost

The above two patents do not involve the use of semiconductor substrates