Abstract
In-Sb-Te 三元合金薄膜，以modified flash deposition 法，已蒸鍍成功。有關此蒸鍍特性亦在論文中加以討論。剛鍍好的薄膜被發現是非晶質與結晶相二者共存的結構。薄膜的均質化可在低於250℃ 的熱處理狀況下達成。最好的熱處理情況是在145至225℃ 的二階段退火。各種不同剛鍍好的膜與退火過的膜藉著 X光繞射儀與穿透式電子顯微鏡，二種儀器來分析其特性。同時也使用AES 來分析鍍層原子的深度分佈特性。一種三元化合物Ｉｎ3ＳｂＴｅ2， 根據過去報導它在低於420℃ 的溫度下是不穩定的會分解成ＩｎＳｂ，與ＩｎＴｅ，然而卻首次在溫度低於250℃ 被生成，此生成特性、退火效果以及在低溫的穩定性均將加以詳細討論。同時，也討論可能的生成機構。二元化合物Ｉｎ2Ｔｅ3，與Ｓｂ2Ｔｅ3的生成也加以檢視。Ｉｎ2Ｔｅ3，化合物乃是經由剛鍍好的Ｉｎ39Ｔｅ61膜，一定要藉著二階段退火才會形成。然而，對於Ｓｂ2Ｔｅ3，化合物從剛鍍好的膜形成而言，卻不需二階段退火。Ｉｎ2Ｔｅ3化合物的生成反應也作了說明。介穩相Ｉｎ4Ｔｅ3在Ｉｎ2Ｔｅ3化合物生成過程中是關鍵物質。 Ｉｎ2Ｔｅ3 與Ｓｂ2Ｔｅ3化合物，二者的光學常數藉橢圓偏光儀來加以測量。利用波長6238Ａ的染料雷射脈衝可使Ｉｎ27Ｓｂ24Ｔｅ49膜產生非晶質。化雷射所幅射區域藉傳統與具有１０Ａ 小探針的STEM來詳細觀察和描述。經過19mW、300ns 的雷射脈衝照射後，在膜表面1.5 微米平方的區域發現是非晶質的，此乃是要使膜非晶質化所需最短的雷射持續時間。當使用19mW ， 且持續時間長於lus 的雷射脈衝照射後產生如“火山口”的坑洞。然而在這些洞的中心，發現具有非晶質與島嶼狀結構的殘留物。同時，經由 EDAX， 發現殘留物與膜有相同成分。在脈衝雷射幅射薄膜實驗中，首次觀察到交替性的帶狀結構。位於脈衝雷射所產生的洞邊緣的帶狀結構是以結晶與非晶質區域交替地出現。此種帶狀結構的生成被認為是歸因於脈衝雷射幅射後熱流的結果。對Ｉｎ27Ｓｂ24Ｔｅ49與Ｉｎ16Ｓｂ17Ｔｅ67膜作了靜態讀寫擦測試。脈衝雷射束對膜的熱效塵，例如非晶質，化融，化再結晶與控洞等現象，均與脈衝束的功率與持續時間有關。也對Ｉｎ16Ｓｂ17Ｔｅ67膜作了寫擦循環測試。書寫脈衝是15mW、500ns，而擦拭脈衝則是8mW、10us。 過經100 次循環後，發現在記憶狀態與擦拭狀態間反射率差異8%。///////Thin In-Sb-Te alloy films have been successfully deposited by modifiedflash deposition. The deposition characteristics have been discussed.The as-deposited films were found to be a structure of amorphous andcrystalline phases co-existing.Homogenization of the films was found to be achieved by the heat treatmentat temperatures lower than 250℃. The best heat treatment condition isthe two-step annealing of 145-225℃. The structure of variousas-deposited films and annealed films were characterized by both the X-raydiffraction analysis (XRD) and transmission electron diffraction analysis(TEM). Auger electron depth profile analysis has been used tocharacterize the homogeneity of the films.A ternary compound★, which has been reported to be unstable at thetemperatures lower than 420, was formed for the first time attemperatures lower than 250 . The formation characteristics, the effectsof annealing, and stability at low temperatures have been discussed indetail. The possible formation mechanism has also been discussed.The formation of the binary compounds, ★and ★, has also been examined.The two-step annealing was found to be necessary to form the ★compoundfrom the as-deposited ★film. However, the two-step annealing is notrequired for the formation of ★compound from the as-deposited ★film.The formation reaction of the ★compound has been elucidated. Themetastable compound ★was found to be the key material in the formation of★compound. The optical constants of the ★and ★compound films has beenmeasured by an ellipsometer.The ★films has been amorphized by a pulsed dye laser with a wavelength of6328A. The laser riradiated areas have been characterized by both theconventional TEM and the analytical scanning TEM with a very small probeof 10 A in size.An area of 1.5 um square on the film surface was found to be amorphous,after the irradiation of pulsed laser beam at 19 mW with a duration of 300ns, which was found to be the shortest duration of pulsed laser beam toamorphize the film. A hole with a shape like "volcanic crater" was foundwhen the duration of laser pulse was longer than 1 us at 19 mW. However,in the center of the holes, the remainder was found to be an amorphous andisland-like structure. The remainder was also found to have the samecomposition as the film identified by the energy dispersive analysis ofX-ray (EDAX).A structure of alternating bands was observed for the first time in thepulased laser beam irradiated film. The banded structure on the edge ofthe pulsed laser beam ablated holes was found to be the appearance ofalternating crystalline and amorphous bands. The formation of bandedstructure was considered to attribute to the heat flow after the pulsedlaser beam irradition.The static read and write test was carried out on the ★film and ★film.The thermal effects of pulsed laser beam on the films, such asamorphization, melt and recrystallization, and ablation, were found to bedepended on the power and duration of the pulsed beam. A write/erasecysling test was carried out on the ★film. The writing pulses are 15 mW,500 ns and the erasing pulses are 8 mw, 10us. After 100 cysles the filmwas found to have a reflectivity difference of 8% between written anderased states. ★ 代表同上中文.