Electrical activation of high-concentration aluminum implanted in 4H-SiC
Electrical activation of high-concentration aluminum implanted in 4H-SiC
复制标题
DOI：
10.1063/1.1796518
复制
发表时间：
2004-10
影响因子：
3.2
通讯作者：
Y. Negoro;T. Kimoto;H. Matsunami;F. Schmid;G. Pensl
中科院分区：
文献类型：
--
作者：
Y. Negoro;T. Kimoto;H. Matsunami;F. Schmid;G. Pensl
研究了4 H-SiC（0001）和（112 <$0）中高剂量Al ~+离子注入。通过霍尔效应测量研究了Al+注入剂量和退火时间对薄膜电学性能的影响。在500°C下注入3.0× 1016 cm-2剂量的Al+，然后在1800° C下进行1 min的高温退火，在（0001）样品中获得了2.3kΩ的薄层电阻（0.2μm深）。在（112 <$0）样品中，即使是室温注入，在1800°C退火后也会产生2.3kΩ闪烁（0.2μ m深）的低薄层电阻。霍尔数据进行了比较，通过使用掺杂浓度依赖的Al受体的电离能确定的计算值。实验得到的自由空穴浓度与理论预期值吻合得很好。空穴迁移率不像在Al掺杂外延层中获得的经验迁移率那么高。实验结果表明，该方法可以有效地提高材料的电性能。
High-dose aluminum-ion (Al+) implantation into 4H-SiC (0001) and (112¯0) has been investigated. The dependences of the electrical properties on the implanted Al+ dose and on the annealing time were examined by Hall-effect measurements. A low sheet resistance of 2.3kΩ∕◻ (0.2μm deep) was obtained in a (0001) sample by implantation of Al+ with a dose of 3.0×1016cm−2 at 500°C and a subsequent high-temperature anneal at 1800°C for a short time of 1min. In the case of (112¯0) samples, even room-temperature implantation resulted in a low sheet resistance of 2.3kΩ∕◻ (0.2μm-deep) after anneal at 1800°C. The Hall data are compared with the calculated values determined by using the doping-concentration dependent ionization energy of Al acceptors. The experimentally obtained free-hole concentrations agree well with the theoretically expected values. Hole mobilities are not as high as the empirical mobilities obtained in Al-doped epitaxial layers. The differences in the electrical properties between the experimental d...