Research Of GaInSb Single-junction Thermophotovoltaic Cells

Thermophotovoltaic cell( TPV) is a sort of photovoltaic devices which could convert infrared radiation to electricity. Thermophotovoltaic system has promising applications and commercial value for it’s highly energy utilization and a wide range of heat sources may be used. Thermophotovoltaic technology has become more and more important. Recently, researching on TPV system focus on researching new cells materials, designing device structure and optimizing grow process.In this work, researching on TPV cells from both experimental and theoretical: on one hand, Ga In Sb thin films are prepared by LP -MOCVD, the effect of growth parameters on thin films morphology is analyzed. On the other hand, Ga In Sb TPV cell is simulated by Silvaco/ Atlas software. The effects of the device parameters and the temperature are analyzed on the device characteristics. Some meaningful results were achieved:(1)Ternary GaxIn1-xSb alloys are grown on Ga Sb substrate by low pressure metalorganic chemical vapor deposition( MOCVD) technique. The influence of growth parameters on the surface morphology of the epitaxial layers are investigated. The optimized growth temperature is 550 oC, the V/III ratio is 1.5、TMIn/III ratio is 0.1 and chamber pressure is 100 Pa. High quality GaxIn1-xSb epitaxial layers have been achieved.(2) The simulation results show that the emitter thickness is 5μm and the base thickness is 0.2μm, the TPV cell gets the highest efficiency. with the increase of the thickness of the active region, the performance gradually decline; when the emitter doping concentration is 3×1017 cm-3, the base doping concentration is 1×1018cm-3, the cell efficiency is the highest. with the increase of doping concentration, the performance declines quickly. The thickness and doping concentration of the window layer has an optimal value. In this case, the window thickness is 0.1μm and the doping concentration is 2×1019cm-3. Back electric layer mainly from the electric field. The thermophotovoltaic cells have a negative temperature characteristic. With the increase of the working temperature, the cell output power will decrease. Along with the increase of the temperature of radiator, the optical power density and spectrum range increases, more conducive to improve the photoelectric conversion efficiency of thermal photovoltaic cells.The simulations are carried out at a radiator temperature of 1473 K and a cell temperature of 300 K. The TPV cell area is 400μm2. Its simulation results: Voc=0.43 V,Isc=6.18A/cm2,Pmax=1.95W/cm2,ηcel=7.35%。...