本研究分為兩部分，第一部分為以聚碳矽烷作為前驅物以化學氣相沉積法製備矽摻雜石墨烯，並以石墨烯作為比較，探討其性質是否不同。我們以拉曼光譜、TEM、XPS、UV-Vis分析其材料特性，在拉曼光譜中的分析中，我們發現了在石墨烯(pristine graphene , PG)及矽摻雜石墨烯(Si-doped graphene, SiG)中，存在著些差異，SiG之D-band強度非常高，且G-band的附近出現一支側峰，以及強度下降的2D-band，這些性質差異應可歸因於矽摻雜入石墨烯中，造成晶格失序所引起的缺陷。
在TEM的分析中，我們仍可發現一些PG與SiG的性質差異，從HRTEM中可清楚地看到石墨烯之蜂巢狀排列，以及其倒晶格空間可觀察到兩個六角環，分別對應到的是{10‾1 0}及{11‾2 0}面，但更進一步的討論其角度及晶面間距，發現角度非60°，且晶面間距大於石墨烯之理論值，推測是Si摻雜所造成之現象，接著我們更進一步地，以XPS確認其成分組成，確認其含有矽的存在，矽的摻雜量約為6.86 %。
第二部分為將矽摻雜石墨烯以及石墨烯應用於蕭特基光感測器之上，利用變溫電性量測系統確認其符合蕭特基元件中的熱離子發射模型，並且SiG與PG之蕭特基能障分別為0.83 eV與0.79 eV，由蕭特基能障可推算出SiG與PG之功函數分別為4.88 eV與4.84 eV，而在溫度為298K時理想因子為1.9與2.6。
接著量測其光感測特性，發現元件具有Self-Power之特性，即為元件可在無外加電壓下操作，經由量測過後，SiG/n-Si蕭特基光感測器的元件效能皆大於PG/n-Si蕭特基光感測器，元件對於紫外光(UV)至近紅外光(NIR)波段的光皆有響應。更進一步地，將元件經過350 °C在100 sccm之10% H2 + 90% Ar之混合氣氛中，退火2小時後，元件的光增益有著明顯的提升。SiG/n-Si蕭特基光感測器之響應度為0.232 A/W，上升/下降時間為2.1 ms/33.9 ms、ON/OFF ratio為~104。
並探討改變入射光強度對於響應度的變化，在入射光強度為~ 8 μW的情形下，元件之響應度提升為1.32 A/W，顯示元件對於弱光也有很好的響應。

This study can be separated into two major parts. Firstly, we synthesized silicon doped graphene (SiG) from polycarbosilane by chemical vapor deposition (CVD) and compared material properties with pristine graphene (PG) which was synthesized by CVD process too.
Raman spectroscopy, TEM, XPS, and UV-Vis were employed to characterize the structure and properties of PG and SiG. Raman spectrum of SiG shows the stronger intensity of D-band and the appearance of a shoulder peak near G-band. This was obvious caused by defect that might be attributed to Si doping to graphene leading deformed lattice structure of graphene.
During TEM characterization, we found some different appearance of SiG from PG. We found two crystal planes {10‾1 0} and {11‾2 0} corresponding to two hexagonal rings. We analysed the angle and d-spacing of SiG where we found that the angle was not 60˚ and the d-spacing was larger than PG and we suggested the reason is Si atom disturbed the lattice structure. Furthermore, we used XPS to confirm the existence of Si and, the content of Si was 6.86 %.
Secondly, we fabricated PG/n-Si Schottky photodetector and SiG/n-Si Schottky photodetector. We measured the I-V curve at different temperatures to assure that our device follows thermionic emission model, and Schottky barrier hight of SiG/n-Si Schottky photodetector is 0.83 eV, higher than that of 0.79 eV of PG/n-Si Schottky photodetector. From Schottky barrier height we could calculate work fuction. The work fuction of SiG and PG were 4.84 eV and 4.88 eV. At 298 K ideal factor of PG/n-Si Schottky photodetector and SiG/n-Si Schottky photodetector were 2.6 and 1.9, respectively.
SiG/n-Si Schottky photodetector performs better than PG/n-Si Schottky photodetector. Our device can response toward a broad incident light range from 365 nm to 852 nm. Furthermore, The devices were annealed at 350 °C in 10% H2 + 90% Ar atmosphere and the flow rate of gas is 100 sccm for 2 hours. For SiG/n-Si Schottky photodetector, responsivity, rising/falling time and ON/OFF ratio were 0.232 A/W, 2.1 ms/33.9 ms and ~104, respectively. We also observed an increase in responsivity of SiG/n-Si Schottky photodetector up to 1.32 A/W, when we decrease the intensity of incident light to ~ 8 μW/cm2.

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