本篇碩士論文，運用TCAD半導體輔助模擬程式研究了結構為P-I-M的穿隧電晶體。藉由新型穿隧電晶體汲極端的金屬，取代了傳統穿隧電晶體汲極端的矽原子，能有效地提高電流開關特性並且簡化製程難易度。根據模擬結果顯示，新型穿隧電晶體P-I-M汲極端選用功函數值為4.25 eV的金屬相對於傳統的穿隧電晶體P-I-N，在元件關閉狀態下，不論大小汲極偏壓，皆能有效地抑制雙極效應，降低漏電流的損耗，在大汲極偏壓下，P-I-M結構增加了載子漏電流的穿隧能障厚度；小汲極偏壓下，P-I-M結構降低了載子的複合率，此外，導通電流對於這兩個結構沒有太大的差異，新結構的漏電流下降了276倍，並提升了兩個數量級的元件導通-關閉電流比值，也降低次臨限擺幅。最重要的是，新型結構P-I-M在實際製程上是容易的，汲極端金屬存在著例如TaSix 與TixSi1-x等矽化物，且金屬功函數存在著0.15 eV的範圍選擇空間，在範圍內P-I-M結構的穿隧電晶體比P-I-N結構擁有更多優勢。

In this paper, a P-I-M TFET is proposed and investigated by TCAD simulator. Using a new n-TFET structure that replaces traditional semiconductor material at drain with metal was proposed to enhance device performance while simplifying process. By employing metal with an appropriate work function (WF) of 4.25 eV, based on simulation results, the proposed P-I-M TFET is superior to traditional P-I-N structure by exhibiting suppressed ambipolar effect for both low and high drain bias due respectively to wider tunneling barrier and lower Shockley-Read-Hall (SRH) recombination rate at off state. In addition, improved off-state current by a factor of 276, enhanced on-state and off-state current ratio (ION/IOFF) by 2 orders and improved subthreshold swing (SS) with comparable on-state drive current are achieved. More importantly, the idea of P-I-M structure is feasible from the viewpoint of process integration since metal with such WF is a fab-friendly material such as TaSix and TixSi1-x, and the variation of metal WF up to 0.15 eV is also allowed to keep the advantage of IOFF over P-I-N TFET. The P-I-M TFET is very to implement green electronics with higher performance at lower cost.

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