造成CIGS模組效率低落的其中一個主因在於Rs過高，經過擬合計算後，我們發現CIGS 模組之Rs高達2.45 Ω-cm^2，為了深入了解串聯電阻來源，本實驗藉由模擬計算推導並驗證TCO的串聯電阻計算公式，另外再製作AZO/iZO/Mo以及AZO/iZO/MoSe2/Mo 的接觸電阻量測結構，期望找出P2接面在有無MoSe2時的ρc落差。
本實驗透過Matlab以及PV lighthouse網站提供的擬合工具，計算了電池模組在不同長度S 時的RS，並繪製成圖以尋找其關係。至於在ρc的方面，我們則透過微影製程以及硒化處理，分別在兩種試片上做出Kelvin及TLM結構，用以量測其ρc。
經實驗後我們得到透明導電層的Rs計算公式約為Rs=1/3 x ρsq × S^2；此外，
AZO/iZO/MoSe2/Mo的ρc約為5.74*10^-2 Ω-cm^2，而AZO/iZO/Mo則1.31*10^-3 Ω-cm^2。如果能夠減少MoSe2在P2接面的影響，便可降低CIGS模組的串聯電阻，進而提高電池效率。

One of the challenges of CIGS solar cell nowadays is that module efficiency is a lot lower than single cell efficiency. This is mainly caused by high RS of cell module. In order to find out where Rs comes from, we used simulating calculation to derive a
formula that can describe the relationship between Rs and cell length S. Also, we made devices on both AZO/iZO/Mo and AZO/iZO/MoSe2/Mo samples to measure ρc difference with and without MoSe2.
For simulation, we used Matlab and fitting tools from PV lighthouse. We drew I-V curves under different S and calculated their Rs. As for ρc, we created Kelvin and TLM structures on two kinds of sample by lithography and selenization. Both of the
structure could help us study ρc. In result, we confirm the formula of Rs in TCO is Rs= 1/3 x ρsq × S^2. Besides that, we
found out that ρc of AZO/iZO/MoSe2/Mo is about 5.74*10^-2 Ω-cm^2, while ρc of AZO/iZO/Mo is about 1.31*10^-3 Ω-cm^2.

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