二矽化鎳成長在超薄矽基板上之成長情形探討

The Growth of NiSi2 on Thin Substrates

馮爾國(Erh-Kuo Feng)

指導教授 ： 蔡哲正

國立清華大學/工學院/材料科學工程學系/碩士(2010年)

https://doi.org/10.6843/NTHU.2010.00289

摘要

如何控制磊晶矽化物的生長，一直是一個熱門的議題。不論是要應用在光電元件或是半導體，抑或是各種感測元件上，若能控制磊晶矽化物長出來的形狀，使其具有規則性，那麼或許將可使其在應用性上產生突破性的發展。我們在這裡討論的，是不使用微影製程的方式，而是讓矽化物以類似自組裝的方式，產生長程有序的結構。
無論如何，要控制矽化物的生長，必須先瞭解其成長的機制，在這篇論文裡，主要探討的是影響NiSi2生長機制的各種因素。另外，關於NiSi2的成長機制，在之前的研究已經證實其成長是由動力學所主導，而其形狀的分布是與機率有關係。由有限元素分析法，我們知道了island結構的高低，影響了其應變能與長寬比之間的關係，若能夠改變並固定NiSi2成長時的高度，並改變其應變能隨長寬比的演變，或許能夠改變其長寬比的分佈。因此我們在這裡設法去控制island的高度，在這篇論文裡，主要是使用應變矽以及SOI(Silicon on insulator)基板來達成我們的目的，利用控制基板的厚度，可以使成長出的island都固定在相同的高度。
實驗結果顯示，改變基板的厚度確實對NiSi2的分佈產生了影響，而長在應變矽基板的又與成長在SOI基板的有些不同，在應變矽基板上的NiSi2可能是受到了應變的影響，而產生了較不規則形狀的結構；而成長在SOI基板上的island與矽基板上的相比，其分佈較偏向窄且長。
藉由改變基板的厚度，我們確實達到了想要改變island成長分佈的目的，也符合我們當初預期的成果，透過這些實驗，也更進一步的瞭解要如何去控制island的成長。雖然我們現在還沒有辦法控制NiSi2長出形狀大小完全一樣，且排列為長程有序的結構，但相信在這邊提供的資料對於未來想要控制island的成長會有實質上的貢獻。

關鍵字

二矽化鎳 ； 磊晶矽化物

並列摘要

How to control the growth of epitaxial silicide has been an issue for many years. If we can control silicide islands to grow into the shape we want, the application of silicide may have breakthrough on many fields, such as optoelectronics industry and semiconductor industry. We don’t discuss with lithography here, but talking about self-growth. Trying to control the self-growth of nickel disilicide to produce ordered structure is our main purpose.
However, we must understand the growth mechanism of nickel discilide in order to control its growth. In this thesis, we study factors which affect the growth of nickel disilicide. In previous research, it has been confirmed that the growth of nickel disilicide is govern by kinetics, and its shape distribution is related to probability. From finite element method, we have known that the height of the structure has significant influence on the relationship between strain energy of the structure and its aspect ratio. If we can change and fix the height of the islands, maybe we can change their shape distribution. Based on this reason, we try to control the height of the islands. In this thesis, we use strained-Si and SOI (silicon on insulator) as substrates to achieve our purpose. By using the thin substrates, we can force all the islands to grow into truncated-hut structure with the same height.
The experimental results have showed that the thickness of the substrate will affect the shape distribution of the islands. The islands which grew on strained-Si are different from which grew on SOI. On strained-Si, the growth of nickel disilicide may be affected by stress field, so the islands grew into irregular shape. On the other hand, the islands grew on SOI are narrower and longer than which grew on Si.
By using the thin substrates, we have achieved the goal of changing the shape distribution of nickel disilicide. Through these experimental results, we have a better understanding of how to control the growth of the islands. Although we can’t control all the islands to grow into the same shape with the same size and same orientation, we still believe that the results provided here will make contributions to the future.

並列關鍵字

NiSi2 ； Epitaxial silicide

參考文獻

2. A. Kikuchi, Atomic-configuration-dependent energy at epitaxial silicide-silicon interfaces. Japanese Journal of Applied Physics Part 1-Regular Papers Short Notes & Review Papers, 1998. 37(2): p. 653.

4. U. Falke, A. Bleloch, M. Falke, and S. Teichert, Atomic structure of a (2 x 1) reconstructed NiSi2/Si(001) interface. Physical Review Letters, 2004. 92(11): p. 116103.

6. R.T. Tung, A.F.J. Levi, J.P. Sullivan, and F. Schrey, Schottky-barrier inhomogeneity at epitaxial NiSi2 interfaces on Si(100). Physical Review Letters, 1991. 66(1): p. 72.

7. P. Werner, W. Jager, and A. Schuppen, Interface structure and schottky-barrier height of buried CoSi2/Si(001) layers. Journal of Applied Physics, 1993. 74(6): p. 3846.

8. S.B. Mi, C.L. Jia, Q.T. Zhao, S. Mantl, and K. Urban, NiSi2/Si interface chemistry and epitaxial growth mode. Acta Materialia, 2009. 57(1): p. 232.