本論文研究分成兩部分，第一部分為討論在無施加應力下，藉由改變矽酸鉿的成分比例及退火溫度來探討薄膜特性的變化。由實驗結果得知矽酸鉿薄膜在快速熱退火後，其結晶性會隨著鉿的成份比例降低而變差，而當薄膜摻雜高比例的矽時，其成分接近二氧化矽，故結晶所需溫度會提高很多。而且在預估成份比例為Hf30Si70的薄膜中，經穿透式電子顯微鏡的表面分析發現經1000℃快速熱退火60秒後其相分離的機制可能為成核生長(Nucleation and Growth) ; 但經950℃持溫60秒後其相分離的機制卻為離相分解(Spinodal Decomposition)。
第二部分先討論應力施加於二氧化鉿薄膜的效應，再探討應力施加於矽酸鉿薄膜的作用。由實驗可得知無應力施加的試片在退火過程中，介面層成長伴隨壓應力的產生，為了釋放此應力將矽原子射出，在二氧化鉿表面形成一層薄薄的覆蓋層，而結晶上的差異主要為二氧化矽覆蓋層產生與否。
接著探討應力施加於矽酸鉿薄膜，由實驗結果得知有施加應力的矽酸鉿薄膜其結晶性比無應力的佳，其主因亦為應力施加於矽酸鉿薄膜可以抑制介面層成長，同時抑制矽向表面擴散形成二氧化矽覆蓋層，使二氧化矽覆蓋層的來源只剩矽酸鉿薄膜相分離出的二氧化矽，可能導致覆蓋層變的更薄或覆蓋的不完全，讓覆蓋層無法有效地影響其結晶性。

In this work, the effects of constrain stresses on the phase separation mechanism, microstructure and electrical properties in Hf-silicate thin films were studied. 7-nm-thick hafnium silicate dielectric films with HfO2 compositions between ~60% to ~10 mol% ((HfO2)x(SiO2)1-x, x = 0.6~0.1) were fabricated by radio-frequency magnetron sputtering. Flexural tensile and compression constraints were applied mechanically to the films on Si substrates, and the magnitude of the constrained strain on the substrate was varied by adjusting screws in holder. The substrates were bent mechanically through the holder into a circular section. As the constrained specimens were removed from the holder after deposition of the film, the substrates were fully recovered that yielded an equivalent but opposite stress to the films. The tetragonal HfO2 phase was formed upon a rapid thermal annealing treatment at 950℃ for 60s. The degree of crystallization of the constrained Hf-rich films was higher than the reference. Notably, the two opposite constrained stresses have similar influences on the crystallinity of Hf-rich silicate. Compared with previous report that showed two distinctly different phase separated microstructures, our study results was consistent with two limiting cases of microstructural evolution: nucleation/growth and spinodal decomposition. The film structure obtained by HRTEM of the HfxSi1-xO2 film with x=0.3 is consistent with the theory of spinodal decomposition after RTA at 950℃ for 60s in N2 gas. And the observed microstructure of the film with x=0.3 has phase separated by a nucleation and growth mechanism after RTA at 1000℃ for 60s in N2.

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