本研究利用標準Bulk CMOS製程中高解析度離子佈植與多層金屬連接層的特性，實現積體化背部電極太陽能電池，選擇0.18、0.35μm CMOS製程中的N-well/P-substrate接面區域設計不同對稱結構，觀察太陽能電池的轉換效率變化，並且以場氧化層(Field oxide)做P-N接面之間的電性隔離達到良好的元件隔絕效果。設計的過程中，皆考量到不同標準CMOS製程的限制，並且能夠通過繁複的物理驗證(DRC)，由於我們佈局太陽能電池是使用標準電路佈局軟體，因此我們所設計的元件能夠輕易的與其他電路作整合。
本實驗室已取得三批成果晶片，量測後發現由於原始晶片的基板厚度過厚以及高電阻與較短的載子活期影響下，在1 mW/mm2的980nm紅外光雷射照射後，測得Voc為0.5~0.52V、Jsc為0.068~0.070mA/mm2、轉換效率約4%，僅能產生出0.04mW/mm2的能量，但經過自行磨薄後製程技術對晶片的厚度進行去除，可成功提升Voc到0.54~0.56V、Jsc到0.25~0.27 mA/mm2，轉換效率亦可提升至12~16%左右並產生出0.16mW/mm2的能量，填充因子則維持在0.7~0.85，在文中亦會討論兩家晶圓廠製程結果的不同，提供將來利用此架構的設計做為參考。

In this thesis, we utilize high resolution doping and multi-layer interconnections provided by standard bulk CMOS processes to implement integrated back-contact solar cells. The diode behavior is realized by parallelly connecting two-dimensional N-well/P-substrate junctions. All heavily-doped contacts are electrically isolated with embedded field oxide in lateral directions to avoid current leakage. The layout of photovoltaic devices within the industry standard electronic design tools is required for the foundry to accept the design for fabrication. Because the processing conditions are optimized for specific design parameters, compliance of the geometric rules is mandatory. Since the on-wafer processing is shared with other customers, as-realized solar cells could be integrated with other microelectronic devices to achieve self-powered system.
The main roadblocks of CMOS solar cells include its thick substrate, high substrate resistivity, and poor carrier lifetime. Under near-infrared (980 nm) illumination with an intensity of 1 mW/mm2, as-realized CMOS solar cell has a open-circuit voltage of 0.5~0.52 V, a short-circuit current of 0.068~0.07 mA/mm2, and a conversion efficiency of only 4%. Therefore, this device could generate a electrical power of 0.04 mW/mm2. By thinning down the substrate to tens of micrometers, this device could increase its open-circuit voltage and short-circuit current to 0.54~0.56 V and 0.25~0.27 mA/mm2, respectively, leading to a conversion efficiency of 12~16% and a generated power of 0.16 mW/mm2. Thinned solar cells have similar filling factor of 0.7~0.85 as original ones.

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