【作者】 孙聂枫；

【导师】 毛陆虹；

【作者基本信息】 天津大学 ， 微电子学与固体电子学， 2008， 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;InP中的VInH4相关的缺陷性质和有关InP材料的应用,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,实现了熔体的富铟、近化学配比,富磷等状态,为进一步开展不同熔体配比对InP性质的影响奠定了基础。相关成果发表在16th IPRM Proceedings;Materials Science In Semiconductor Processing;Journal of Rare Earths;Chinese Journal of Semiconductors, IOCG-2007 Proceedings.等会议和刊物上。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。相关成果在16th IPRM Proceedings; 8th ICSICT;Journal of Rare Earths;半导体学报等会议和刊物上发表。3、利用常温Hall,变温Hall,光致发光谱(PL),付立叶变换红外吸收谱(FT-IR)及正电子寿命谱等对富铟、近化学配比、富磷中的缺陷进行了深入分析。测试结果表明:富磷条件下生长的InP材料含有相对较高浓度的浅施主和浅受主杂质或缺陷,富磷条件下生长的InP材料中有与铟空位VIn结合而成的复合能级的存在,InP材料中铟空位与氢的复合体VInH4在非掺InP材料中为浅施主,其在富磷熔体条件下具有较高的浓度、富铟熔体条件下浓度最低。在10-300K的温度范围,用正电子寿命谱分析了用不同配比条件的InP材料,测量表明,样品中含有不同浓度的铟空位和氢的复合体,VInH4。在富磷样品中可以观测到比较高浓度的VInH4,如果温度足够地可以观测到电阻率的升高。研究表明在掺Fe的InP中的VInH4浓度比在未掺杂中的高。而在同一晶锭中其浓度分布是头部高,尾部低。讨论了其对未掺杂InP的电子特性和掺Fe的InP的补偿的影响,及其对InP热稳定性的影响。相关成果在13th SIMC; Journal of Rare Earths;18th IPRM;Journal of Physics and Chemistry of Solids;Materials Science And Engineering B;中国电子科学研究院学报;半导体学报等会议和刊物上发表。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) A large quantity of high purity InP crystal material has been produced by the phosphorus in-situ injection synthesis and liquid encapsulated Czochralski (LEC) growth process. In the injection method, phosphorus reacts with indium very quickly so that the rapid polycrystalline synthesis is possible. The quartz injector with two or multi-transfer tubes was used to improve the synthesis result. It will avoid quartz injector blast when the melt was indraft into the transfer tube. The injection speed, melt temperature, phosphorus excess, and so on are also important for a successful synthesis process. About 4000-6000g stoichiometric high purity poly InP is synthesized reproducibly by improved P-injection method in the high-pressure puller. We firstly reported these results in 16th IPRM Proceedings;Materials Science In Semiconductor Processing ; Journal of Rare Earths ; Chinese Journal of Semiconductors, IOCG-2007 Proceedings.(2) Long-length 2-inch, 3-inch, 4-inch semi-insulating InP single crystals have been grown by the HP-LEC method. The maximum total length of the 2-inch single crystal part was 190mm, the maximum total length of the 3-inch and 4-inch single crystal was 150mm. The key technologies of reducing twining were discussed in this paper. It is found that by carefully adjusting the thermal symmetry of the heating field and by further improving the quality of the polycrystalline, the diameter 100-142mm twin-free InP crystals can be obtained even with a shoulder angle of up to 35°-90°, and defects caused by thermal decomposition appear on the surface of the crystals during pulling.(3) Some samples from these ingots have been characterized by Hall Effect and Fourier Transform Infrared (FT-IR) spectroscopy measurements respectively. The Hall Effect and FT-IR spectroscopy measurement results indicate that the carrier concentration of P-rich undoped InP is higher than that of In-rich and stoichiometric undoped InP materials. The intensive absorption peaks indicate that our phosphorus in-situ injection synthesis LEC undoped InP materials have relatively high concentration of hydrogen related complexes. It has been proved to be acting as a shallow donor in InP material by theory calculation. Generally, high concentration indium vacancy should enhance the formation of higher concentration of VInH4 complex. It is the stoichiometric condition that causes the InP materials grown from P-rich melts higher carrier concentration than that of In-rich InP. The extra donor is hydrogen indium vacancy complex.The concentration of VInH4 in Fe-doped InP is higher than that of undoped InP. The concentration of VInH4 is high in wafers from the top of an ingot and low from the tail of an ingot. The influence of this complex on the electrical properties of n-type LEC undoped and compensation in Fe-doped InP is discussed. The results reveal the influence of VInH4 on the thermal stability of InP material due to the fact that bond of hydrogen complex is weak and dissociates easily upon annealing.Positron lifetime measurements have been carried out on liquid-encapsulated Czochralski-grown undoped InP samples sliced from the middle part of ingots over the temperature range 10–300 K. And at 70 K, the spectra have been measured in darkness, under illumination of infrared LED, and with illumination off is one sample. The measurements at low temperature reveal different concentration of hydrogen indium vacancy complex VInH4 in these samples. A relatively higher concentration of VInH4 in samples grown from P-rich undoped InP melts can be shown. The increase of resistivity of these samples can be speculated when temperature is low enough.更多还原