- 學位論文
採用氮化鎵並聯串疊元件的功率模組封裝熱分析和布局設計研究
Heat dissapation analysis and topology design of Power Module with Cascode GaN devices
摘要
AlGaN/GaN HEMT相較於矽功率電晶體具備可在高溫下運作、高導熱性以及高飽和電子漂移速度等特點，此外也具較低導通電阻，也因此導通功率耗損較低，能源效率也較高。然而隨著功率的提升，元件的通道溫度也會升高，一旦通道溫度升高，將會使元件效能及可靠度下降。而為了改善元件效能下降的狀況，找出幫助封裝元件妥善散熱的方法十分重要。本研究將使用熱模擬分析軟體Ansys Icepak來模擬元件運作時的溫度分布，再利用IR熱像儀來驗證模擬溫度分布的正確性，藉由以上兩種方式可得到熱堆積的位置，此資訊可幫助分析找出散熱方法。 本研究對單顆氮化鎵封裝元件及氮化鎵功率模組(PM)進行熱模擬及實際實驗，以了解封裝元件及功率模組施加功率時的溫度分布及散熱狀況。此外，透過調整氮化鎵排列方式，由直線型排列調整為田字型排列，將氮化鎵功率模組(PM)中的氮化鎵元件溫度分布調整至均勻的狀態。同時調整銅片的布局方式也可以協助散熱。至於熱模擬及實驗的部分，經修正模擬參數(銀膠熱傳導係數)及仔細考量實驗所需要素(MOS消耗功率)，調整後模擬溫度與實際實驗溫度趨近。本研究由模擬與實驗方法佐證調整功率元件模組布局後的溫度分布狀況，提出熱分析及功率元件基板布局散熱設計。
並列摘要
Compared with the traditional silicon-based power devices, AlGaN / GaN power transistors have high electron mobility, high thermal conductivity and also can operate well at high temperature. In addition, AlGaN / GaN power transistors also have lower on resistance, which reduce the power loss during the operation of transistors, and make the energy consumption more efficiently. However, following by the increase of the power, the tunnel temperature of components will also increase, and this will influence the reliability and performance of power devices. It is important to find out the method to help heat dissipate from the components properly. This study is carrying on using the thermal analysis software-Ansys Icepak to simulate the conditions while the power devices are operating, and aquire the temperature profile of those. Additionally, we will conduct the experiment and use the IR camera to measure the temperature of power devices, which can make sure whether the result of simulation is correct or not. With these two methods mentioned above, the accurate position where the heat accumulate in the components is shown, and the information can help us figure out how to dissipate the heat from them. The thermal simulation and practical experiments are also performed on the single gallium nitride package element and the gallium nitride power module (PM) to understand the temperature distribution and heat dissipation of the package element and power module when power is applied. By adjusting the gallium nitride arrangement from linear arrangement to rectangular-shaped arrangement, the temperature distribution of the gallium nitride elements in the gallium nitride power module (PM) is adjusted to a uniform state. At the same time, adjusting the layout of the copper sheet can also be helpful for heat dissipation. As for the part of thermal simulation and experiment, after modifying the simulation parameters (the thermal conductivity of the silver) and carefully considering the required elements of the experiment (MOSFET power consumption), the simulation temperature can approximately match the experimental temperature. In conclusion, we use thermal simulation and experiment to prove that the temperature distribution of the gallium nitride elements in the gallium nitride power module (PM) can be uniform after adjusting the gallium nitride arrangement, and we propose the Heat dissipation analysis and topology design of Power Module with Cascode GaN devices.