Two-dimensional simulation of silicon avalanche cathodes
Two-dimensional simulation of silicon avalanche cathodes
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DOI：
10.1109/16.275232
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发表时间：
1994
影响因子：
3.1
通讯作者：
Yicheng Lu;M. Wang;B. Lalevic
中科院分区：
文献类型：
--
作者：
Yicheng Lu;M. Wang;B. Lalevic
利用二维器件模拟器PISCES-IIB研究了硅雪崩阴极作为一种具有超浅p-n结的新型电子发射器件的特性。稳态仿真结果表明，由于制造过程造成的非平面表面拓扑结构导致电流在表面台阶存在的发射区边缘附近拥挤。在反向偏置增加的情况下，电流拥挤降低了发射均匀性，也降低了发射电流。当阴极上的反向偏压增加时，非平面表面结构也会导致外延层的穿孔。因此，阴极电流对发射的贡献百分比降低，从而降低了发射效率。仿真结果表明，与击穿后相同的电流相比，在阴极偏置高于12 V时，流经发射区的阴极电流比例下降了30%。这也影响总发射电流的增加速率，总发射电流是发射效率和总阴极电流的乘积。>
The characteristics of silicon avalanche cathode as a novel electron emitting device with ultra-shallow p-n junctions have been studied using the two-dimensional device simulator PISCES-IIB. The steady-state simulation indicates that the nonplanar surface topology resulting from fabrication process causes current crowding near the edge of the emitting area where the surface step exists. Current crowding degrades the emission uniformity and also reduces the emission current under increased reverse bias. The nonplanar surface structure also causes punchthrough in the epitaxial layer as the reverse bias on the cathode increases. As a result, the percentage of the cathode current contributing to emission decreases, reducing the emission efficiency consequently. The simulation shows that the portion of the cathode current that flows through the emitting area drops to as much as 30% at cathode bias higher than 12 V, compared to the same current just after breakdown. This also affects the rate of increase in the total emission current which is the product of the emission efficiency and the overall cathode current. >