| The optoelectronic devices working in 3-5 μm, such as light emitting diode, infared detector, laser are of high demand for the applications in medical diagnostics, environmental monitoring, biomedicine and mineral exploration. The ternary alloy In As1-xNx and In As1-xSbx are excellent candidates for the fabrication of infrared optoelectronic devices. Liquid phase epitaxy(LPE), which works in a near thermodynamic equilibrium growth mode, inherently provides high-quality material, and thus is suitable for the fabrication of perfect crystallinity In As1-xNx and In As1-xSbx films.In this work, high quality In As1-xNx and In As1-xSbx films were obtained by LPE technique. The structural, optical and electrical properties of films were characterized and analyzed. Then, the In As Sb-based device structure was obtained by LPE technique. The main research rasults and research progress are described below:(1) The LPE system has been improved. The new LPE equipment realizes the automation of LPE growth. Computer-controlled automatic push of the boat in the new system replaced the manual push of the boat in the old system, which improved the stability of pushing the boat and accuracy of positioning. A new-style graphite boat, which reduced the disturbance in the process of LPE growth, replaced the old-style graphite boat. In addition to a main temperature controller, an auxiliary temperature controller was installed in the new system, which extended the length of constant temperature zone. The nitrogen and hydrogen channels’ on, off and switch in the new system can be controlled automatically. Positive and negative pressurizing devices improve the safety of the whole system. The repeatability and the yield of the sample have been improved greatly by this new LPE system, and high quality epilayer can be obtained.(2) In As1-xNx epilayers were grown on In As substrates by LPE technique. The growth parameters and the In N powder’s placing way were optimized to increase the nitrogen content in the film. The cross-section morphologies and the surface morphologies of the epilayers were characterized by scanning electron microscope(SEM) measurements and atomic force microscope(AFM) measurements, respectively. High-resolution x-ray diffraction(HRXRD) measurements were used to investigate the structural properties of the epilayers. The nitrogen composition of the film is up to 0.66%. The full width at half maximum(FWHM) of In As1-xNx film is comparable to that of In As substrate, indicating the high crystalline quality of film. The fundamental energy band gaps of In As1-xNx films obtained from Fourier transform infrared(FTIR) transmission spectra are found to decrease with increasing nitrogen content.(3) In As1-xSbx epilayers were grown on In As substrates by LPE technique. High quality In As1-xSbx epilayer with x>0.10 was grown on In As1-xSbx buffer layer with x<0.10 on In As substrate. The structural properties, cross-section morphologies, lattice defects and optical properties of In As1-xSbx epilayers were investigated comprehensively by HRXRD, SEM, transmission electron microscope(TEM), FTIR, photoluminescence(PL) and infrared spectroscopic ellipsometry(SE) measurements, respectively. The cutoff wavelength of In As1-xSbx film at room temperature is up to 4.6 μm.(4) A combinational purification procedure including prolonging baking time in hydrogen and adding rare-earth element gadolinium(Gd) to the source materials was applied to reduce the residual impurities in the In As1-xSbx epilayers. The conductive In As substrate of In As0.94Sb0.06/In As sample was removed completely by chemical mechanical polishing(CMP) method to eliminate its influence on the electrical properties of In As0.94Sb0.06 film. The electrical properties of purified In As0.94Sb0.06 films were characterized and analyzed by Hall measurements. The optical properties of purified In As0.94Sb0.06 films were characterized and analyzed by FTIR and PL measurements.(5) The In As Sb-based p Bin device structure was grown on n-type In As substrate by LPE. The device structure was optimized using In As0.92Sb0.08 epilayer as buffer layer to reduce the dislocation in the In As0.87Sb0.13 active layer, In As0.67Sb0.14P0.19 quaternary alloy with wide band gap as cladding layer to reduce the dark current. The HRXRD, SEM, TEM and PL measurements were carried out to investigate the sructural properties, lattice defects and optical properties of each epilayer. The current-voltage characteristics and photoresponses of the detector were also presented.
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