Study on electron emission from nanocrystalline silicon

利用脉冲激光烧蚀技术在纳米晶硅薄膜上制备了平面型阴极，并对其发射特性进行了研究。虽然在栅极电压与栅极材料的功函数一样低的情况下观察到发射电流，但发射效率最高时为0.5%。发射电流波动为平均发射电流的50%左右。能量分布相当广泛，表明电子在纳米硅层和栅电极内部有强烈的散射。目前这些结果还不够。然而，我们相信，通过优化激光烧蚀和栅极的条件，可以提高发射特性和可靠性，因为激光烧蚀是制备纳米晶硅薄氧化层的合适技术。

We have fabricated planar-type cathodes based on nanocrystalline silicon thin films deposited by using a pulsed laser ablation technique and examined their emission characteristics. Though the emission current was observed at the gate voltage as low as the work function of the gate material, the emission efficiency was 0.5% at the maximum. The emission current fluctuation was the oder of fifty percent for average emission current. The energy distribution was considerably broad, indicating that electrons were strongly scattered inside the nc-Si layer and the gate electrode. These results are not enough at present. However, we believe that the emission characteristics and reliability will be improved by optimizing the conditions of the laser ablation and the gate electrode, because a laser ablation is an appropriate technique is for fabricating nanocrsytalline Si covered with a thin oxide layer.