微致冷器之致冷特性數值模擬分析

Numerical Analysis of Cooling Characteristics of Microcoolers

陳瑞霆(Jui-Ting Chen)

指導教授 ： 洪銘聰

國立中央大學/工學院/能源工程研究所/碩士(2011年)

摘要

隨著電子產業的興盛，高運算量的積體電路需求逐漸增加，在增加積體電路的高運算量時，也同時造成電路的熱管理問題。對於解決此晶片熱集中的問題，熱電致冷器即是一種非常有潛力的解決辦法， 其中又以微型致冷器可能可與積體電路製作於同一封裝內，而更受矚目。本文鑒於目前文獻中對微致冷器研究的探討不足，例如微致冷器使用熱電偶時的量測誤差，或基底效應及幾何效應衍生的現象都沒有加以說明，因此在本文對微型致冷器進行系列模擬分析。
本文首先對於微型致冷器模型中可能造成量測差異的問題進行分析，於此處定義了熱端電極之尺寸及位置，其可使量測差異降至0.3%之下。另外得知使用熱電偶進行微致冷器溫度的量測會造成一定的誤差，量測到的致冷溫差會較小。
之後進行微致冷器致冷效率的模擬，於此處得知對於微型致冷器而言，尺寸過小而不足以使其發揮理論之致冷效能，也因為如此進而造成，對於同一熱電優值，降低熱傳導係數比提昇電傳導係數更有幫助。另外，並對微致冷器面積上升，致冷溫差下降的因素作解釋。對於微致冷器之非等向的熱傳導係數是否影響致冷也進行了討論。
最後進行微致冷器於晶片散熱的分析，模擬結果顯示，對於微致冷器而言，面積小則有較大的單位面積汲熱量，但考慮到晶片面積可容納之致冷器數量及致冷器間距，則是以大面積的致冷器可帶走的總熱較多，因此對於散熱而言，必須視散熱對象為熱點散熱或是整體晶片散熱，而對微致冷器面積尺寸作不同之選擇。

關鍵字

數值模擬 ； 微致冷器 ； 熱電

並列摘要

With the rapid development of integrated circuit, thermal management has been a more important issue. Thermoelectric coolers (TEC) are important research area to solve this problem. For TEC, microcoolers has gained attention recently because of its potential high cooling power.
When review many of research documents, we found there has few analysis for microcoolers characteristics. Such as using thermocouple measure cooling temperature will has some error, and substrate or geometry may cause effect. This paper use 3D thermoelectric simulation to analyze the performance of microcoolers.
At first, we analyze the model of microcoolers. We defined size and location for the hot side electrode. Later, we simulate using thermocouple to measure cooling temperature and confirm there will cause some error.
Then we analyze performance of microcoolers. In this simulation, we found decrease thermal conductivity is better than increase electoral conductivity for the some thermoelectric figure of merit. On the other hand, we explain why increase microcoolers area, cooling temperature will be decrease.
Final, we simulate microcoolers using on chip. Numerical analysis indicated that the small area cooler has better cooling power densities. But consider total area of chip, larger area cooler may have better total cooling power. Therefore, we have different size choice for hot spot cooling or total chip cooling.

並列關鍵字

thermoelectric simulation ； thermoelectric ； microcooler

參考文獻

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