本研究旨在以濺鍍法於矽基板上成長單晶鍺薄膜與單晶矽鍺薄膜，濺鍍之優勢在於製程不需使用有毒氣體且成本較低，若成功在矽晶圓上成長低表面缺陷之單晶鍺薄膜或單晶矽鍺薄膜則有機會能夠取代價格昂貴的鍺晶圓。矽的加入對於鍺薄膜來說具有降低差排錯位密度、提高光學能隙、減少薄膜吸光的效果，當矽鍺合金中，矽的含量小於15%時，對於提高能隙的效果最為明顯。此外，矽鍺的晶格常數會比鍺低，有助於成長高能隙的材料磷化鎵。 我們成功的在矽晶圓上以75 W、300℃、5 mTorr的製程條件製作出腐蝕坑密度為1.18×105 cm-2的(400)方向單晶鍺薄膜。矽鍺薄膜則在製程加氫氣、150 W、450℃、5 mTorr的製程條件成長出腐蝕坑密度為7.48×105 cm-2的(400)方向單晶矽鍺薄膜。且成功利用矽的加入將鍺的光學能隙由0.67~0.69 eV的範圍提升至0.74~0.81 eV。 ;This research aims at growing single crystalline germanium and silicon germanium thin films on silicon wafers by a sputtering method. The advantage of the sputtering method is its nontoxic process. If the single crystalline germanium or silicon-germanium films include low surface defects on silicon wafers, there will be the opportunity to replace the germanium wafer. Silicon alloyed germanium thin films can reduce the threading dislocation density, increase the optical band gap, and reduce the absorbance of the thin films. When the silicon content is less than 15% in the silicon-germanium alloy, the increasing in the band gap is obvious. Finally, we have achieved the single crystalline germanium thin film on the silicon wafer with an etch-pit density of 1.18×105 cm-2, and the silicon-germanium thin film on the silicon wafer have achieved an etch-pit density of 7.48×105 cm-2. Moreover, we have increased the optical band gap of germanium thin film from the range of 0.67~0.69 eV to 0.74~0.81 eV by increasing silicon content.
