【作者】 周晓龙；

【导师】 杨克武； 杨瑞霞；

【作者基本信息】 河北工业大学 ， 微电子学与固体电子学， 2010， 博士

【摘要】 磷化铟（InP）已成为光电器件和微电子器件不可或缺的重要半导体材料。本文详细研究了快速大容量合成高纯及各种熔体配比条件的InP材料;大直径InP单晶生长;与熔体配比相关的缺陷性质;半绝缘InP晶片的制备,主要获得以下结果:1、深入分析InP合成的物理化学过程,国际上首次采用双管合成技术,通过对热场和其他工艺参数的优化,实现在60-90分钟内合成4-6Kg高纯InP多晶。通过对配比量的调节,实现了熔体的富In、近化学配比,富P等状态,为进一步开展不同熔体配比对InP性质的影响奠定了基础。2、通过对晶体生长中孪晶形成和位错增殖的机理研究,优化热场条件,调整工艺参数,生长了具有国际先进水平的5.5英寸整锭InP单晶,并生长了长190mm的半绝缘InP单晶。3、采用原位P注入法合成不同化学计量比的InP熔体,利用LEC法分别从富In、近化学配比和富P的熔体中生长的InP晶体。测试结果表明:富P熔体中LEC生长的InP晶体材料剩余载流子浓度较高,与富In熔体条件相比,其差值约为1～2×10¹⁵cm^-3。证明了LEC生长的InP晶体材料中存在较高浓度的In空位与H的复合体VInH4,该复合体的浓度随熔体的化学计量比条件:富In、近化学配比、富P的改变依次升高。4、通过对掺Fe和非掺退火两种半绝缘InP晶片的电学补偿进行了比较,分析了这两种半绝缘InP材料中深能级缺陷对电学补偿的影响。在掺Fe半绝缘InP材料中,由于存在高浓度的深能级缺陷,这些缺陷参与电学补偿,材料的补偿强度低,降低了材料的电学性能。相比之下,非掺退火半绝缘InP材料中深能级缺陷浓度很低,通过扩散掺入的Fe受主作为唯一的补偿中心钉扎费米能级,因而表现出优异的电学性质。由于Fe原子通过扩散占据了In位,深能级缺陷被有效地抑制,材料的电学补偿度得到保证。综合深能级缺陷和电学性质的测试结果,证明了半绝缘InP单晶材料的电学性能、热稳定性、均匀性等与材料中一些深能级缺陷的含量密切相关。通过分析深能级缺陷产生的规律与热处理及生长条件的关系,给出了抑制缺陷产生、提高材料质量的途径。更多还原

【Abstract】 Indium Phosphide （InP） has been indispensable to both optical and electronic devices. This paper used a direct P-injection synthesis and LEC crystal growth method to prepare high purity and various melt stoichiometry conditions polycrystalline InP and to grow high quality, large diameter InP single crystal in our homemade pullers. In this work, we have obtained the following results:1. The synthesis of InP polycrystalline has been deeply analysed. It is the first time to use double-tube injector on the world. By optimizing the thermal field and other parameters, it can be achieved to synthesize 4 to 6 kilograms polycrystalline InP of high purity in 60 to 90 minutes. The InP melt of different stoichiometric- ratio such as In-rich and P-rich has been obtained by means of adjusting the weights of indium and red phosphorus, and it established the base of the study of the different stoichiometric ratios on the characteristics of InP.2. By use of the results of the research work of twinnings and dislocations, the conditions of the thermal field and the process parameters has been modulated. The maximum diameter of single crystal could be reached to 5.5 inch and the maximum length of the semi-insulating single crystal was 190mm.3. The in-situ P injection method was used to synthesize and the LEC method was used to pull the different stoichiometric-ratio InP single crystals. It has been tested that, the carrier concentration of InP materials pulled from P-rich melts is about 1-2×10¹⁵cm^-3 higher than that from In-rich melts. It is proved that there has been a relative high concentration of VInH4 in the InP materials pulled by the LEC method. The concentration of VInH4 is highest in the P-rich melts and lowest in the In-rich ones.4. Through a comprehensive study of the deep level defects in the Fe-doped and undoped annealed InP wafers, it has been confirmed clearly that the Fe-doped semi-insulating InP one has higher concentration of deep level defects which participate in the electrics compensation so that the electrics performance is reduced, however, there is lower concentration of deep level defects in the undoped annealed InP and the deep level defects are restrained so that the electrics compensation can be ensured. The electrics performance, thermal stability, homogeneity and so on are closely related to the deep level defects in the materials. The approaches to restrain the defects and improve the quality of the materials were given by analyzing the rules of deep level defects and the relationship between heat treatments and growing conditions.更多还原