Hsiao Hao-Tse, Ni I-Chih, Tzeng Shien-Der, Lin Wei-Fan, Lin Chu-Hsuan
Department of Opto-electronic Engineering, National Dong Hwa University, Shoufeng, Hualien 974, Taiwan.
Department of Physics, National Dong Hwa University, Shoufeng, Hualien 974, Taiwan.
Nanoscale Res Lett. 2014 Nov 27;9(1):640. doi: 10.1186/1556-276X-9-640. eCollection 2014.
Gold nanoparticles (AuNPs) have been deposited on n-type Ge photodetectors to improve the responsivity. Two different coverage ratios, including 10.5 and 30.3% of AuNPs have been prepared, and the fabricated photodetectors are compared with the control sample. The 1,310-nm responsivities at -2 V of the control, 10.5% AuNPs, and 30.3% AuNPs samples are 465, 556, and 623 mA/W, respectively. The AuNPs could increase the responsivities due to the plasmon resonance. The reflectance spectra of these samples have been measured to verify that plasmon resonance contributes to the forward scattering of incident light. The reflectance decreases with AuNP deposition, and a denser coverage results in a smaller reflectance. The smaller reflectance indicates more light could penetrate into the Ge active layer, and it results in a larger responsivity.
金纳米颗粒（AuNPs）已沉积在n型锗光电探测器上以提高响应度。制备了两种不同的覆盖率，分别为10.5%和30.3%的AuNPs，并将制备的光电探测器与对照样品进行比较。对照样品、10.5% AuNPs样品和30.3% AuNPs样品在-2 V时的1310 nm响应度分别为465、556和623 mA/W。由于等离子体共振，AuNPs可以提高响应度。已测量这些样品的反射光谱，以验证等离子体共振有助于入射光的前向散射。随着AuNP沉积，反射率降低，且覆盖率越高反射率越小。较小的反射率表明更多的光可以穿透到锗有源层中，从而导致更大的响应度。
