Structural Design Of Nano-trench Patterned Substrates And Lateral Epitaxial Growth Of InP/GaAs

Monolithic integration of ?-? compound semiconductors such as InP on silicon substrate has attracted attention for decades because of its potential application in the field of silicon photonics, optical interconnections, and Complementary Metal Oxide Semiconductor(CMOS) technology beyond Moore's law. Monolithic integration of ?-?s on Si is the logical extension of the present day microelectronics and optoelectronics components. The requirement is to deliver a platform that not only integrates the advantages of both technologies but also reduces the cost and results in smaller footprint than current conventional components. The idea has driven the microelectronics and optoelectronics researchers around the globe for a couple of decades now and numerous efforts have been made to achieve this integrated platform. InP based alloys that offer favourable wavelengths have attracted interest for integration of InP based compounds on Si, particularly due to their use in long haul communication and also for short-reach high-data rate communications as e.g. relevant for data centers or high-performance computing. The need for InP on Si is long sought. The optoelectronics and microelectronics industry have seen a need for integrating direct bandgap materials like InP and GaAs (?-?s) with Si, an indirect bandgap material. The world has already seen an enormous reduction in size of both electronic and photonic components. Any further miniaturization and integration of Photonic Integrated Circuits (PICs)with Electronic Integrated Circuits (EICs) to achieve active optoelectronics components on Si require monolithic integration of both.Research groups around the globe have been working extensively on integration of ?-?s on silicon. However, it is still difficult to integrate InP on Si. If the GaAs substrates lead to heterogeneous growth of high quality InP epitaxial layer, we can combine the advantages of GaAs substrate with the advantages of InP-based devices, but also combine the advantages of GaAs high-speed electronic devices to achieve optoelectronic integration.1. The effect of the quantitative relationship between the thickness of the mask and the width of the mask on the blocking dislocation proportion was investigated, and the design of the nano-trench patterned substrate could be optimized. So that in the lateral epitaxial experiment can be high-quality InP epitaxial layer. It is found that the blocking proportion increases with the increase of the aspect ratio, and the blocking proportion varies with the direction of the mask under the same aspect ratio.2. The GaAs pattern substrate with SiO2 as the mask was prepared and the surface treatment before the lateral epitaxial growth was completed. The nano-trench pattern substrates have 0°,30° ,45°,60° , 90° , and the width is 110nm, the thickness is 250nm. They were prepared by deep ultraviolet lithography, dry etching and other techniques.The surface treatment scheme of the patterned substrate was explored,and the preparation for the later lateral epitaxy experiment was made.3. InP / GaAs planar substrate growth experiment was optimized with another Metal Organic Chemical Vapor Deposition (MOCVD), and the optimized growth conditions were explored, including growth temperature, growth time, ?/? ratio, reaction chamber pressure and so on. In order to achieve selective growth, coalescence and planar growth,the optimized experimental conditions are obtained: the growth temperature of GaAs buffer layer is 720 ?, growth thickness is 30nm.The growth temperature of the growth of InP buffer layer at low temperature is 450 ?, and the growth thickness is 40 nm. The growth temperature of InP buffer layer at high temperature is 655 ?, and the total thickness of the three layers is 1800 nm.