應用於Power IC之700伏特LIGBT元件研發

Abstract

近年來，由於平面顯示器和通訊產品的推陳出新，使得功率元件的需求大幅增加。為了順應電路積體化的潮流，將功率元件與低壓電路整合在同一晶片上，傳統垂直式的元件結構也必須改善為橫向式設計，因此本文針對橫向絕緣閘雙極性電晶體（LIGBT）做一研究與發展。 應用RESURF（Reduced Surface Field，簡稱RESURF）的原理，可以將功率元件做在矽晶片的薄磊晶層上。本文根據空乏區電荷分享理論為基礎並加以計算，在根據計算的結果以Tsuprem4與Medici等電腦輔助設計軟體工具，對LIGBT元件進行各種特性模擬分析，包括靜態崩潰電壓（BV值）、導通電流（Ic）等。最後運用園區某半導體製程公司裡的100V/0.5um高壓製程，實作出耐壓達700V的LIGBT元件。實驗中，做了許多製程的參數對照組。量測結果，在某些預定的參數的實驗組中，其LIGBT元件的耐壓皆可達700V以上，並且在實作上與模擬做一比較，說明各種模擬方式與實作上的異同與可行性。

In recent years, following the rapid progress of the flat panel displays and communication products, the demands for power devices have increased substantially. To approach the target of circuit integration, the traditional discrete vertical power devices needs to be changed to lateral structures so that they can be integrated with the low voltage components on the same chip. Therefore, in this thesis concentrates on the development of the lateral insulated gate bipolar transistor (LIGBT). The power devices have been successfully built on a thin epi-layer in this thesis by employing the principles of Reduced Surface Field (RESURF) on a silicon chip. The charge sharing theory in the depletion layer of the power device has been studied through the theoretical computation as the design assistance. Furthermore, through the aid of Tsuprem4 and Medici computer aided design tool, the physical and electrical characteristics of LIGBT devices have been simulated and studied including the static breakdown voltage, conductive current and so on. The LIGBT devices have finally fabricated successfully under the environment of semiconductor corporation’s 100V/0.5um-high-voltage-process. Many process parameters have been arranged in the experiments. The breakdown voltages of the devices fabricated with some specific parameters are over 700V in all. All the simulation results and measurement results have been compared and analyzed to demonstrate the implementation possibility of our designs.