Hopping conduction range of heavily Al-doped 4H-SiC thick epilayers grown by CVD
Hopping conduction range of heavily Al-doped 4H-SiC thick epilayers grown by CVD
复制标题
CVD 生长的重掺铝 4H-SiC 厚外延层的跳变传导范围
DOI：
10.7567/apex.8.121302
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发表时间：
2015
影响因子：
2.3
通讯作者：
H. Okumura
中科院分区：
文献类型：
--
作者：
S. Ji;K. Eto;S. Yoshida;K. Kojima;Y. Ishida;S. Saito;H. Tsuchida;H. Okumura
为了概述跳跃导电范围，CVD生长的重掺杂Al的4 H-SiC厚外延层（2.0 × 1019-4.0 × 1020 cm−3）的电特性在宽温度范围（20-900 K）下进行了研究。研究发现，在100 K以下，所有外延层的载流子输运都以跳跃传导为主，相应的跳跃传导激活能在1.1 × 1020 cm−3附近显示出最大值1.30 meV。随着掺杂浓度的增加，电阻率随温度的变化规律逐渐演化，最终在整个温度范围内都服从T1/T1/4定律，这是变程跳跃导电的直接证据。
To outline the hopping conduction range, the electrical characteristics of CVD-grown heavily Al-doped 4H-SiC thick epilayers (2.0 × 1019–4.0 × 1020 cm−3) were investigated in a wide temperature regime (20–900 K). It is found that, below 100 K, hopping conduction dominates the carrier transport for all epilayers, and the corresponding hopping conduction activation energy shows a maximum of ∼30 meV at around 1.1 × 1020 cm−3. With increasing doping level, the temperature dependence of resistivity evolves and finally obeys the ∼1/T1/4 law in the entire temperature regime, which gives direct evidence of variable-range hopping conduction.