近來，矽化鍺薄膜由於可調變的能隙特性及和積體電路製程的高度相容性，成為一前途看好的材料，並已經廣泛應用在高速元件及光電子元件上。 目前已經有多個沉積矽化鍺薄膜在不同基板的技術，然而為了取得高效能的表現，矽化鍺薄膜必須沉積在高溫環境或者於沉積後給予薄膜高溫熱退火處理製程。為了避免掉高溫處理這個步驟，我們建構了一新式的沉積技術，在常溫下沉積矽化鍺薄膜於矽基板上並且沒有進行後續的熱退火處理。由於二氧化碳雷射能夠在反應時被當成一能量源誘發矽甲烷熱解成氣相，我們利用二氧化碳雷射，輔助傳統的電漿增強化學氣相沉積系統沉積矽化鍺薄膜在矽基板上。

　　在我們設計的系統中，ㄧ個外加的波長10.6微米二氧化碳雷射被引導照射進去標準的電漿增強化學氣相沉積系統的反應腔體中，並且運用波長為632.8奈米的可見光氦-氖雷射輔助二氧化碳雷射以大角度88o入射至腔體內的矽基板上，再同時以氬氣稀釋成4 %濃度的矽甲烷和純的鍺烷為氣體反應物來源沉積矽化鍺薄膜在矽基板上。

　　首先，為了研究有雷射和無雷射輔助沉積的矽化鍺薄膜表面粗糙度及薄膜深度各濃度含量，我們量測了原子力顯微鏡及歐傑電子光譜儀。除此之外,為了探究薄膜的結晶性及化學鍵結，我們量測了拉曼光譜及傅立葉轉換紅外線光譜。矽鍺薄膜的電特性方面則是量測了霍爾效應量測系統及四點探針量測系統。

　　根據量測結果，我們可以發現經過雷射輔助成長的矽鍺薄膜較沒有雷射輔助成長的薄膜表面平滑，且鍺元素含量在有雷射和無雷射輔助成長的薄膜中相差不多。而根據拉曼光譜的結果，我們可以研判經過雷射輔助成長的矽化鍺薄膜其結晶性比無雷射輔助成長薄膜來的佳，而另ㄧ方面，我們根據傅立葉轉換紅外線光譜的量測結果中震動模態的矽氫鍵結，推算矽化鍺薄膜內氫含量濃度多寡。計算結果顯示，在矽氫鍵結的振動模態其高斯分佈的模擬，沒有雷射輔助沉積的矽化鍺薄膜其氫含量濃度高於有雷射輔助沉積的矽化鍺薄膜含量。根據霍爾效應量測結果也可以發現沒有雷射輔助成長的矽鍺薄膜載子漂移率較有雷射輔助成長的薄膜低了許多。因此本研究成功以二氧化碳雷射輔助電漿化學氣相沉積系統於常溫下沉積出含氫量低，使矽鍺鍵結增強的高品質矽化鍺薄膜。

　　Recently, silicon–germanium (SiGe) film has been become a promising material in applications of high-speed devices and optoelectronic devices, due to its tunable bandgap and compatibility with integrated circuit process. Several techniques have been used to deposit SiGe film on various substrates. To obtain high performances, however, the deposited SiGe films must be deposited or annealed at elevated temperature. To avoid the undesirable treatment in high temperature, we proposed a new technique to deposit SiGe films on Si substrate at room temperature without post-annealing treatments. Since CO2 laser can be used as an energized source to induce gas-phase pyrolysis of SiH4 in a reactor, we used CO2 laser to assist the deposition of SiGe films on Si substrate in conventional plasma-enhanced chemical deposition system (PECVD).

　　In our system, CO2 laser with a wavelength of 10.6 μm was collimated into the chamber of the conventional PECVD system. To assist the alignment of CO2 laser beam with a incident angle of 88o to the Si substrate, a visible He-Ne laser (632.8 nm) was used. To deposit SiGe films on Si substrate without heating, argon-diluted SiH4 (4%) and pure GeH4 were used as reactant gas sources.

　　Initially, the surface uniformity and depth homogeneity of the SiGe films deposited with and without CO2 laser assistance were conducted from atomic force microscopy and Auger electron spectroscopy measurements. In addition, the crystalline structure and chemical bonds of these films were analyzed using Raman spectroscopy and Fourier transformation infrared spectrometry (FTIR). The electrical properties of SiGe films are measured by Hall measurement and four point probe measurement.

　　According to the measured result, it can be seen that the surface roughness of the SiGe film grown with CO2 laser assistance is much better than that without CO2 laser assistance. Besides, the atomic concentration of Ge between a-SiGe:H thin films with and without CO2 laser assistance is similar in the same order. According the Raman spectrum, it can be deduced that the Si-Ge films prepared from LAPECVD have better crystallization. Furthermore, hydrogen concentration (NH) was estimated from Si-H rocking mode bond (Si-H(r)) of SiGe film observed from the FTIR spectrum. Hydrogen concentration derived from Si-H(r) mode in the SiGe films deposited without laser assistance is higher than that deposited with laser assistance. Because the CO2 laser beam could assist the pyrolytic decomposition of SiH4 gas and enhance the formation of Si-Ge bonds to induce less hydrogen. According to the Hall measurement result, the Hall mobility of SiGe films grown without laser assistance is much lower than that of SiGe films prepared with CO2 laser assistance. As a result, we concluded that SiGe films possessed superior Si-Ge bond and lower hydrogen concentration can be achieved by PECVD system using CO2 laser assistance.

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