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利用高真空PECVD系统在p型单晶硅上沉积掺磷n型纳米硅薄层(nc－Si:H)，形成纳米硅/单晶硅Np异质结二极管,通过C－V和J－V测试研究了二极管的电学性质。C－V特性指出该异质结为突变型。J－V特性表明二极管具有很好的温度稳定性和整流特性。正偏压时二极管存在两种输运机制：小偏压时（<0.8V）二极管电流由 耗尽层纳米硅薄层一侧的载流子复合过程决定，纳米硅薄层由于能带弯曲而减小了禁带宽度，这是该二极管温度稳定性好的根本原因；大偏压（>1.0V）时电输运符合电荷限制电流（SCLC）模型。负偏压时电流主要来自空间电荷区中的产生电流。

The heterojunction diodes of n－type nanocrystalline silicon on p－type crystalline silicon were fabricated and electrically characterized. The nanocrystalline silicon layer (nc－Si:H) was deposited in a plasma enhanced chemical vapor deposition system. Electrical properties were investigated by capacitance－voltage and current－voltage measurements at different temperature.The capacitance－ voltage results con－firm that it is an abrupt heterojunction. Currentvoltage characteristics show good temperature stability and good rectifying properties. Two carrier transport mechanisms are believed to be the origin of the for－ward current. At low bias voltage (V<0.8 V), the current is determined by recombination at the nanocrystalline side of the space charge region. The bending of band reduces the bandgap of the nanocrystalline silicon layer and, therefore, the activation energy for the recombination process. It is the main reason for the good temperature stability of the heterojunction. While, at higher bias voltages (V>1.0V), the current becomes space charge limited.