本論文利用0.18 ?m CMOS標準製程實現矽累崩光檢測器，此累崩光檢測器主要由N-implant、P-well構成累崩區，p-substrate形成吸光區。利用MEDICI二維元件模擬軟體及實際下線晶片的量測證明累崩光檢測器可同時兼具光響應度及頻寬；在逆向偏壓為11.27 V情況下，元件量測所得響應度約為3.75 A/W，3-dB頻寬可達3.0 GHz。同時引入Deep N-well層數，比較元件有無DNW之差異。接著透過金屬層區隔累崩區及吸光區，累崩區遮光之元件量測的響應度約1.17 A/W，3dB頻寬提升至4.8 GHz。此外，本論文針對矽累崩光檢測器之吸光區作進一步的分析，隨著累崩區面積的下降，放大因子隨著產生的光載子減少而下降。而隨著吸光區寬度的減少，所蒐集到的光載子中擴散電流成份減少也導致頻寬的增加。論文中也利用光脈衝量測，針對擴散載子對頻寬的影響進行驗證。最後我們利用量測所得之S參數萃取累崩光檢測器的模型參數，得到此光檢測器的等效電路模型後，並聯一單極點頻率響應電流源，模擬光電流，並進行頻率響應的電流源參數調整，分析影響本論文光檢測器速度的主宰因素。

This work demonstrates a lateral avalanche photodetectors (APDs) by standard 0.18?m CMOS technology. In the proposed APD, we used n-implant/p-well to compose the avalanche region, and used metal layer to distinguish the absorption region and avalanche regions. At reverse bias of 11.27 V, the 3-dB bandwidth of APD is 3.0 GHz with the responsivity of 3.75 A/W. As in the proposed APD structure with Deep-N-Well layer, the 3-dB bandwidth is decreased to 1.0 GHz due to the extra depletion region at the p-well/DNW and p-substrate/DNW. The extra depletion regions could collect more photo-generated carriers but including diffusion carriers. The measured 3-dB bandwidth of proposed APDs will be improved when the reverse bias is within the avalanche region. At reverse bias of 11.3 V, the 3-dB bandwidth can be increased to 4.8 GHz. The possible reason may be attributed to the peaking effect in the frequency response. From the small signal analysis, we establish an equivalent circuit model including a parallel connected capacitance and an inductance due to the avalanche process. When the APD operates at high reverse bias voltages, the included LC equivalent circuit provides a resonance from the avalanche effect, which introduces a peaking phenomenon to further improve the frequency response. Finally, we discuss the differences between APDs with different absorption region widths. The highest M-Factor is about 148.84, and the best 3-dB bandwidth is 5.4 GHz at reverse bias of 11.73 V for the APD with 0.43 ?m absorption region width. As the avalanche region size decreases, the M-Factor decreases to 65.25 for the APD with 3.44 ?m absorption region width. And the 3-dB bandwidth is decreased to 0.7 GHz due to the diffusive photogenerated carriers as the absorption region width increases.

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