半導體製造中有許多製程都必須在加熱結束後冷卻到一特定的溫度，才能進行下一個製程。而本研究所針對的即是氣體冷卻這個部份。本研究中所模擬的腔體為圓柱腔體，腔壁的溫度為373K，在腔體底部放一溫度1300K，直徑300mm及厚度0.7mm的圓形熱板，並且在腔體的壁上分別設一個進氣口及一個出氣口。在冷卻過程中，以氮氣做為主要的冷卻氣體，吹入腔體的氣體溫度為常溫300K。首先觀察在沒有氣體進入腔體內時的冷卻速率以及對於熱板表面溫度均勻性的影響，接著分別考慮在不同的流速，不同的熱板轉速，不同的入口高度及角度下對於熱板的影響。而所探討的為10秒內的變化。

根據本文的結果可知，當入口流速增快時，也就是增加進入腔體的體積流率時，可以使熱板的冷卻速率增快。在流速增快到10m/s時，冷卻速率可達到9.12K/s。而且在增加熱板轉速後，經由熱板旋轉所帶動的氣流也能夠增加冷卻速率，並且能夠改善熱板的溫度均勻性。而將入口移往靠近熱板的地方也可增加冷卻速度。且經由改變氣體進入腔體的角度更可以改善熱板的溫度均勻性。

In order to carry out next process, sometimes we must cool the products to a specific temperature after heating process in semiconductor manufacture. This paper is to aimed at gas cooling. The chamber is a cylindrical one, and the temperature of chamber wall is 373K. Then put a hot plate which temperature, diameter and thickness are 1300K, 300mm and 0.7mm in the bottom of chamber. In the wall of chamber has a inlet and a outlet. In cooling process, the main cooling gas is nitrogen, and the temperature is 300K. First we consider the situation with no cooling gas entering into the chamber, then consider the situation of different inlet velocity, different rotating speed of hot plate, different height of inlet and angle, separately. Then discuss their cooling rate and temperature uniformity of hot plate.

From the result of this paper, we can obtain that, when increasing the inlet velocity can increase the cooling rate of hot plate. When the velocity is 10m/s, the cooling rate can reach 9.12K/s. And we also find that, when increasing the rotating speed of hot plate can increase the cooling rate, and improve the temperature uniformity. Then we move the inlet to the place near the hot plate, this can increase the cooling rate. If we change the angle of inlet, can also improve the temperature uniformity.

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