【摘要】 研究了2100keV高能量钒注入4H-SiC制备半绝缘层的方法和特性,注入层的浓度分布用蒙特卡罗分析软件TRIM进行模拟.采用一种台面结构进行I-V测试,发现钒注入层的电阻率与4H-SiC层的初始导电类型有很大关系.常温下,钒注入p型和n型4H-SiC的电阻率分别为1·6×1010和7·6×106Ω·cm.测量了不同退火温度下的电阻率,发现高温退火有利于钒的替位激活和提高电阻率,由于钒扩散的影响1700℃退火使得电阻率略有下降.测量了n型SiC钒注入层在20~140℃时的电阻率,计算出钒受主能级在4H-SiC中的激活能为0·78eV.更多还原

【Abstract】 Vanadium ion (V~+) implantation at a high energy (2100keV) is successfully used to form semi-insulating layers in 4H-SiC.The fabrication processes and measurements of the implanted layer are reported in detail.The profile of the ion implantation is simulated with the Monte Carlo simulator TRIM.Test patterns on semi-insulating 4H-SiC samples are processed into a mesa structure,and resistivity measurements are conducted.The resistivities of V~+-implanted layers are strongly dependent on the conduction type of the initial 4H-SiC samples,and they are about 1.6×10~ 10 and 7.6×10~6Ω·cm respectively for p- and n-type samples at room temperature.The resistivities of the as-implanted samples increase with increasing annealing temperature for both p- and n-type samples due to the introduction of compensating levels.However,they decrease slightly beyond 1700℃ due to the diffusion of vanadium.The temperature dependent resistivity behavior in V~+-implanted n-type 4H-SiC indicates an activation energy of 0.78eV.更多还原