Five-dimensional alloy growth of AlInGaNAs and fundamental investigation for realizing Opto-Electronic Integurated Circuits

从去年开始，我们已经开始了使用包括In的氮化物半导体如InN/Si、InNAs/Si、InGaNAs/Si在Si衬底上生长二维、三维和四维合金膜的基础研究，作为获得具有高膜质量的AlGaInAsN/Si的5维合金生长的初步研究，并且澄清了晶体生长的一些问题。结果，根本上不可能在高温下生长包含In的氮化物半导体，并且膜质量随着In浓度的增加而急剧劣化。此外，发现InN具有比长期以来普遍认为的值（1.9eV）窄的带隙能量（0.7eV）。在研究含In氮化物半导体的5维合金生长时，需要考虑InN的修正带隙能的影响。今年，我们研究了在包含In和In的氮化物半导体的合金生长中向窄带隙能量变化的原因。 ...更多信息 探讨了利用氮化物半导体材料实现光电集成电路的可能性。此外，我们还尝试在GaAs衬底上生长InN和GaN薄膜，并研究了最佳生长条件。通常已知的是，六方GaN和-InN晶体是在单晶硅和-GaAs衬底上获得的。然而，当在500-600 ℃的低温下直接生长时，我们发现在这些具有相同晶体结构的衬底上可以生长出具有高薄膜质量的单晶GaN和-InN。这表明OEIC在未来很有可能实现。从InN薄膜的退火实验中，我们发现，它是可能的，通过在生长过程中施加衬底电压来控制膜中的氧浓度，因此，我们成功地控制了InN的带隙能量。虽然必须考虑膜中氧杂质的影响，但其原因并不总是在膜中形成具有宽带隙能量的In 2 O3晶粒。我们提出了氧在氮化物半导体的5维合金生长中的积极影响，以实现OEIC。少

Since last year, we have started fundamental investigation of 2-,3- and 4-dimensional alloy film growth on Si substrates using nitride semiconductors including In such as InN/Si, InNAs/Si, InGaNAs/Si as a preliminary research for obtaining 5-dimensional alloy growth of AlGaInAsN/Si with high film quality, and clarified some problems on crystal growth. As a result, it is fundamentally impossible to grow nitride semiconductors including In at high temperatures and the film quality abruptly degraded with an increase of In concentration. Furthermore, it was found that InN has a band-gap energy (0.7 eV) narrower than the value (1.9 eV) have been generally believed for long time. It is necessary to take the effect of the revised band-gap energy of InN into consideration for researching 5-dimensional alloy growth of nitride semiconductors including In. This year, we have investigated the cause of change into narrow band-gap energy for alloy growth of nitride semiconductors including In and in … More vestigated the possibility of new material using' nitride semiconductors for realization of optical electrical integrated circuits (OEIC) in the future. Furthermore, we tried to grow the InN and GaN films on GaAs besides Si as a substrate for OEIC and investigated the optimum growth conditions. It is usually known that hexagonal-GaN and -InN crystals were obtained on cubic-Si and -GaAs substrates. However, when being grown directly at low temperatures such as 500-600 oC, we found that single cubic-GaN and -InN with high film quality could be grown on these substrates with the same crystal structure. It indicates the high possibility of realization of OEIC in the future. From annealing experiments of InN films, we found that it was possible to control oxygen concentration in the film by applying the substrate voltage during growth and, as a result, we succeed in controlling the band-gap energy of InN. The cause is not always the formation of In2O3 crystal grains with wide band-gap energy in the film although the effect of oxygen impurities in the film must be considered. We submit the positive influence of oxygen in the 5-dimensional alloy growth of nitride semiconductors for realization of OEIC. Less