用于低温辐射体(≤1000℃)能量转换的锑化物热光伏(TPV)电池技术是一种高输出电功率密度、高稳定性、安全可靠的热电直接能量转换技术，成为一个研究热点。用于此的电池最佳禁带宽度(Eg)在0.5eV以下。本项目用低压MOCVD法生长GaSb基晶格失配GaInSb(Eg≤0.5eV)薄膜。引入GaInSb组份渐变缓冲层降低外延层和衬底之间的失配应力。研究晶格"过冲"对渐变层表面残留应变的影响，优化结构和工艺以降低穿透位错密度。在缓冲层上生长GaInSb有源层，制备TPV器件并测试其性能。通过对实验测试和理论分析相结合，研究失配导致的穿透位错和GaInSb/缓冲层界面态对器件性能的影响，揭示其物理机理，探索降低其影响的途径。利用GaInSb的载流子自吸收特性为器件引入背反电极，理论上实现以光厚电薄为目标的结构优化。项目对推动高效低成本低温辐射体TPV技术的发展具有重要的理论意义和实际应用价值。

Thermophotovoltaic(TPV) systems convert heat into electricity directly,which have the advantages of high output power densities,non pollution and noise etc.Recently, narrow bandgap antimonide-based TPV cell for low temperature(≤1000℃) radiation conversion have received extensive attention because of their high stability and safety coefficient characteristics.The optimum bandgap(Eg) of TPV cell that applied in low temperature should be lower then 0.5eV, and GaInSb can get this Eg by adjusting compositions.This project proposed a lattice-mismatched GaInSb(Eg≤0.5eV)/GaSb thin film TPV cell.The GaInSb thin film will be fabricated on GaSb substrate by LP-MOCVD, and a graded buffer layer is incorporated to accommodate the lattice mismatch between the epitaxial layer and substrate.The effect of crystal lattice "overshoot" on the residual strain near the surface of graded buffer layer will be studed.The structure and growth parameters will be optimized to reduce the densities of threading dislocations.The GaInSb active layer will be grew on buffer layer,and GaInSb TPV device simple will be fabricated and tested.Based on the theoretical simulation and experimental data of the practical material and device,the characteristics of threading dislocations and GaInSb/buffer interface state will be studied to reveal their impact mechanisms on the performances of TPV cell,and the way to reduce this impact will be studied in detail.Based on the strong self-absorption effects of GaInSb,the back surface reflector is adopted to let the photons double pass the active p-n junction,and the structure will be optimized.This project has important theoretical and application significance for developing high efficiency nerrow bandgap TPV cell for low temperature heat source energy conversion.