Sun Hu, Fan Qian, Ni Xianfeng, Luo Qiang, Gu Xing
Institute of Next Generation Semiconductor Materials, Southeast University, Suzhou 215123, China.
Micromachines (Basel). 2025 Apr 9;16(4):442. doi: 10.3390/mi16040442.
This study employed low-pressure chemical vapor deposition (LPCVD) SiN as both the gate dielectric layer and surface passivation layer, systematically investigating the effects of different growth conditions on the dielectric layer quality, two-dimensional electron gas (2DEG) characteristics, interface trap density, and devices' performance, thereby optimizing the growth parameters of LPCVD SiN. The experiment investigated the effects of growth parameters such as the growth temperature, chamber pressure, and gas flow ratio on the growth rate of SiN during the process of growing SiN using the LPCVD technique. Further studies were performed to analyze the impact of SiN introduction on the 2DEG performance. The results indicated that both Si-rich and N-rich SiN compositions could enhance the 2DEG density improvement induced by SiN passivation. The impact of the gas flow ratio on the interface trap density is studied. Through the quantitative characterization of the interface trap density using the pulse-mode I-V method and frequency-dependent capacitance-voltage (C-V) measurement, the results show that the interface trap density decreases with an increased Si-to-N ratio.
本研究采用低压化学气相沉积（LPCVD）氮化硅作为栅极介电层和表面钝化层，系统地研究了不同生长条件对介电层质量、二维电子气（2DEG）特性、界面陷阱密度和器件性能的影响，从而优化LPCVD氮化硅的生长参数。实验研究了在使用LPCVD技术生长氮化硅的过程中，生长温度、腔室压力和气体流量比等生长参数对氮化硅生长速率的影响。进一步开展研究以分析氮化硅引入对二维电子气性能的影响。结果表明，富硅和富氮的氮化硅成分均可增强由氮化硅钝化引起的二维电子气密度提升。研究了气体流量比对界面陷阱密度的影响。通过使用脉冲模式I-V方法和频率相关电容-电压（C-V）测量对界面陷阱密度进行定量表征，结果表明界面陷阱密度随硅氮比的增加而降低。
