Research and development of selective area MOVPE process for the fabrication of monolithic OEIC devices

本研究主要针对选择性区域MOVPE制程的研究与发展，此制程可能是一种制作单片集成光学元件（OEIC）的好方法。在用MOVPE法生长InGaAsP基化合物半导体薄膜时，薄膜生长只发生在晶体表面，而不发生在部分沉积在GaAs或InP衬底上的介质掩模上。该过程被称为选择性生长，并且在化合物半导体薄膜的情况下，生长速率将通过生长区域和掩模区域的面积比来提高。这就是为什么我们称之为区域选择工艺，这也是利用该工艺制造OEIC的原因。SA-MOVPE具有通过设计合适的掩模来制造OEIC的潜力。然而，由于缺乏动力学信息，这使得它非常困难，因此许多研究人员正在尝试和错误的努力来制造器件。在这项研究中，我们研究了气相和表面 ...更多信息 首先，我们采用CFD（计算机流体动力学）模拟来分析商业反应器中从入口到出口的生长速率和组成分布。我们开发了一个反应模型，可以解释CFD计算中的生长速率和成分分布。该模型可以解释生长速率和In/Ga比，这可以解释我们模型的准确性。该模型不能很好地解释As/P比值，因此仍然存在问题，但这并不是一个严重的问题，因为大部分剖面由III族元素分布决定，生长速率和成分不均匀性也是分析反应化学的信息。当我们生长InGaP、InGaAs或InGaAsP时，选择性生长区域中的In/Ga比具有不均匀性。我们可以从InP生长的生长速率不均匀性分析In物种的反应粘附概率，从GaAs生长的生长速率不均匀性分析Ga物种的反应粘附概率。我们发现In/Ga比的不均匀性是由于In和Ga物种之间的粘附概率的差异造成的。这些动力学信息可以用来设计最佳的掩模图案，以开发OEIC，而无需任何实验试验。少

This study focused on the research and development of Selective Area MOVPE process, which may be a good candidate to produce monolithically integrated optical devices known as OEIC. During the growth of InGaAsP based compound semiconductor thin films by MOVPE, film growth will occur only on the crystal surface, but not on the dielectric mask which is partly deposited on the GaAs or InP substrate. This process is called selective growth and in the case of compound semiconductor thin films, the growth rate will be enhanced by the area ratio of growth region and mask region. This is the reason why we call it Area Selective process and this is also the reason for utilizing this process to fabricate OEIC. SA-MOVPE has a potential to produce OEIC by making a suitable mask design to fabricate it. However, the lack of kinetic information makes it quite difficult, so that many researchers are making try & error efforts to make the devices. In this study, we investigated the gas-phase and surfac … More e reactions which may control the SA-MOVPE process.First, we employed CFD (Computer Fluid Dynamics) simulation to analyze the growth rate and composition profile in a commercial reactor from the inlet to the outlet. We have developed a reaction model that can explain the growth rate and composition profile in CFD calculation. The model proposed here could explain the growth rate and In/Ga ratio, which may explain the accuracy of our model. The As/P ratio could not well explained by this model, so there still remain a problem, but it is not so a serious issue, because most of the profile is determined by the group-Ill elements distribution.The growth rate and composition non-uniformity is also informative to analyze the reaction chemistry. When we grow InGaP, InGaAs, or InGaAsP, the In/Ga ratio in the selectively grown region has non-uniformity. We could analyze the reactive sticking probabilities of In species from the growth rate non-uniformity of InP growth and the reactive sticking probabilities of Ga species from growth rate non-uniformity of GaAs growth. We could find that the non-uniformity of In/Ga ratio was originated from the difference of sticking probabilities between In and Ga species. These kinetic information can be used to design optimum mask pattern to develop OEIC without any experimental trials. Less