Heteroepitaxial Growth Of InP On GaAs Using Low-temperature InGaP Buffer Layers With Graded Composition

With the rapid development of optical fiber communication technologies, the applications of WDM and all-optical network technologies have been the research hotspot, and the novel integrated optoelectronic devices are prerequisite to these technologies. The major outstanding issue, which has been encountered during the investigation of integrated optoelectronic devices, is compatibility of heterogeneous semiconductor materials.The compatibility of heterogeneous semiconductors integration can be solved using the prediction of new material systems, wafer bonding and heteroepitaxy respectively.In this thesis, a great deal of research work has been done. It is mainly focused on the InP/GaAs heteroepitaxy using low temperature In_xGa_1-xP graded buffer, and on this basis the metamorphic In_0.53Ga_0.47As PIN Photodetector was fabricated on GaAs substrate. The main contents and achievements are listed as follows:1. InP/GaAs heteroepitaxy based on low temperature GaAs and graded In_xGa_1-xP buffers has been carried out with low pressure metal organic chemical vapor deposition (LP-MOCVD), mainly the growth condition of In_xGa_1-xP graded buffers was optimize. The linearly graded growth mode was used to obtain In_xGa_1-xP buffer (X=0.49â†'1). Test results indicated that the optimum growth temperature (Tg) and ramp time of In_xGa_1-xP graded buffer are 450℃and 500s respectively, the thickness of In_xGa_1-xP graded buffer is 250nm according to Transmission Electron Microscope (TEM) measurement. For 1.2μm thickness InP epilayers, the FWHM of DCXRDω-29 andωscans are 380arcsec, 446arcsec, respectively.2. The heteroepitaxial growth of InP on GaAs was done using low temperature GaAs buffer and low temperature In_xGa_1-xP graded buffers under optimum growth conditions, 48nm In_0.53Ga_0.47As layer was grown inside the normal InP epilayer. Characterization results show that the peak wavelength of In_0.53Ga_0.47As room temperature photoluminescence (PL) emission spectrum is located at 1643nm, and the FWHM value is 60meV.3. Based on InP/GaAs heteroepitaxy using low temperature GaAs and graded In_xGa_1-xP buffers, and the relational results of our research group, 15 periods InP/Ga_0.1In_0.9P strained layer superlattice (SLS) was grown inside normal InP epilayer to improve the quality of the epilayers. For 1.2μm thickness InP epilayers grown by this method, the FWHM of DCXRDω-29 andωscans are 315arcsec and 340arcsec respectively. 10 periods Ino.53Gao.47As/h1P MQWs was grown on the InP epilayer, test results show that the peak wavelength of room temperature PL emission spectrum is located at 1570nm, and the FWHM value is 35.4meV. The image of TEM shows that the SLS effectively reduce the density of threading dislocation in epilayers.4. Using the technology of InP/GaAs heteroepitaxy based on low temperature In_xGa_1-xP graded buffers and Ga_0.1In_0.9P/InP SLS, the metamorphic In_0.53Ga_0.47As PIN photodetectors was fabricated on GaAs substrate. The related work is underway for the experimental parameter has to be optimized.