GaSb基晶格失配GaInSb薄膜的生长及其应用于热光伏电池的基础研究

项目名称： GaSb基晶格失配GaInSb薄膜的生长及其应用于热光伏电池的基础研究

项目编号： No.61204071

项目类型： 青年科学基金项目

立项/批准年度： 2013

项目学科： 信息四处

项目作者： 彭新村

作者单位： 东华理工大学

项目金额： 24万元

中文摘要： 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。

中文关键词： GaInSb；组分渐变缓冲层；热光伏电池；LPMOCVD；表面微结构

英文摘要： 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 impa

英文关键词： GaInSb；compositionally step-graded buffer layer；thermphotovoltaic cells；LPMOCVD；surface microstructure