在本篇論文中，我們將採用簡單的幾何模型來推導圓柱形接面的電場解析公式，並運用開發的等效梯形模組，去模擬圓柱形接面之特性現象。而其中每個梯形等效電路，是由兩個三角形模組所組。接著藉由這些推導出的解析公式與模擬出的特性圖中，我們可以觀察並體會到圓柱形接面之電場特性與一些細部的現象呈現。另外也使得我們對於平面接面與圓柱接面有了更多的體認，而其中值得注意的是平面接面的電場為現性增加，而圓柱接面的電場為超線性增加，且在兩者內建電壓相同之情況下，超線性增加的圓柱接面會得到較高的最大電場值，也導致其崩潰電壓較低。

In this thesis, we will use a simple geometric model to derive the analytic formulas of electric field and use the developed trapezoidal module to simulate the characteristics for cylindrical PN junction. The equivalent circuit of each trapezoid is composed of two triangular modules. Through these analytic formulas and simulated characteristic results, we can observe the characteristics of electric field and some detailed phenomena. In addition, we also have more understanding of the plane junction and the cylindrical junction. It is worth noting that the electric field of the plane junction is linear and the electric field of the cylindrical junction is superlinear. Since the built-in voltages of the two are the same, the cylindrical junction has a larger maximum electric field, which also results in a lower breakdown voltage.

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