.inas / Gasb System Uncooled Infrared Detection Materials

Type-ⅡInAs/GaSb superlattices materials,which can be used to fabricate the uncooled infrared photodetectors,were grown on(100) GaSb substrate in a horizontal quartz reactor low pressure metal organic chemical vapor deposition(LP-MOCVD). The effects of growth parameters on the crystal quality of the InAs/GaSb superlattices infrared materials were discussed,the device materials structure was characterized, and the material structure was discussed in theory.Proper period thickness of InAs and GaSb was contrived to suppress the Auger recombination effectively.Then,type-ⅡInAs/GaSb superlattice materials were measured by means of double crystal X-ray diffraction,the lattice mismatch between the epitaxial layer and substrate was only-0.43%.The properties of interfacial layers of the superlattices were investigated by Raman scattering spectrum,the respective interracial structure can be chosen to reduce the strain at the interface,hence the growth quality of the material will be improved.The surface morphology of the material was characterized by means of atomic force microscopy,and the effects of different growth parameters on surface morphology were discussed,the best surface morphology can be obtained through optimizing the growth parameters.Eventually, photoluminescence results measured show that the peak wavelength of the type-ⅡInAs/GaSb superlattices at 77K is 3.25μm;it means that the material could be a good candidate to detect methane.