| 학회 | 한국재료학회 |
| 학술대회 | 2018년 가을 (11/07 ~ 11/09, 여수 디오션리조트) |
| 권호 | 24권 2호 |
| 발표분야 | A. 전자/반도체 재료 분과 |
| 제목 | Self-separation of GaN Layer Grown by HVPE on MOCVD-GaN/Sapphire Substrates with Implantation of Hydrogen Ion on MOCVD-GaN Layer |
| 초록 | Gallium nitride (GaN) is a III-V compound semiconductor material that exhibits direct energy-gap with a band-gap of 3.4 eV. It has advantages in material characteristics such as high breakdown voltage and high thermal conductivity, which can be important factor in performance of devices such as high brightness light emitting diode (HB-LED) and high electron mobility transistor (HEMT). Recently, hydride vapor phase epitaxy (HVPE), molecular beam epitaxy (MBE) and metal organic chemical vapor deposition (MOCVD) techniques were utilized to grow a GaN layer. However, crystal defects due to lattice mismatch between GaN and mother substrate are generated in the conventional GaN layer growth on the Sapphire substrate. These crystal defects hinder the improvement of device performance in HB-LED and HEMT. In this paper, the separation interface was formed by hydrogen ion implantation for self-separation. The self-separation process with hydrogen ion implantation shortened the GaN wafer fabrication process and prevented cracking of the GaN layer due to thermal expansion coefficients (TEC) difference between GaN layer and Sapphire substrate in thick GaN growth. GaN layer was grown by MOCVD (MOCVD-GaN) on the sapphire substrate with the thickness of 1.7 μm. The hydrogen ion implantation process was utilized to form hydrogen ion band inside the MOCVD-GaN layer with the depth of 300 nm. Then, a heat treatment was applied to form blisters which will be used as a separation interface. After that, Around 800 μm-thick GaN layer was grown on the MOCVD-GaN layer by HVPE at 990 ℃. During cool-down after HVPE GaN growth, the thick GaN layer was self-separated with the stress induced by the difference of TEC between GaN and Sapphire. We utilized transmission electron microscopy (TEM), scanning electron microscopy (SEM) with cathodoluminescence (CL) accessory and optical profiler to analyze the tendency of hydrogen ion dose to self-separation and characteristics of the samples. This work was financially supported by the Brain Korea 21 Plus Program in 2018. This research was supported by the Commercialization Promotion Agency for R&D Outcomes(COMPA) funded by the Ministry of Science and ICT(MSIT). [2017K000350] |
| 저자 | 이재언, 심재형, 박진성, 심태헌, 박재근 |
| 소속 | 한양대 |
| 키워드 | <P>HVPE; GaN; Self-separation</P> |
