本實驗利用掃描式光電流顯微鏡(Scanning Photocurrent Microscopy，SPCM)研究光電元件的光響應特性。
藉由掃描式光電流顯微鏡量測染料敏化太陽能電池光電流分佈，其表面光電流分不是不均勻的。在不同雷射波長入射下，可發現由於染料對於各種波長光吸收率不同，而產生的光電流量也有所不同。
利用掃描式光電流顯微鏡量測單根SnO2奈米線元件的光電流分佈，藉由輸入不同偏壓，發現其光電流分佈有往反向偏壓電極處移動的現象，這可以證明電洞於奈米線內載子傳輸占有很重要的角色，進一步去分析奈米線光電流剖面分佈趨勢，可從中計算出電子與電洞的擴散長度。

In this study, the photoresponse characteristics of photonic devices have been investigated by using scanning photocurrent microscopy (SPCM).
The nonuniform distribution of photocurrents in dye-sensitized solar cells (DSSCs) was measured by SPCM. The magnitude of generated photocurrent is different at different excitation wavelength. According to the N719 absorption spectrum, the different magnitude of photocurrent is attributed to the different absorption of N719 dye at different wavelength.
We investigated the photoresponse characteristics of single SnO2 nanowire device by scanning photocurrent microscopy. The maximum photocurrent position shifts toward the hole collector (negatively biased electrode) with increasing bias voltage, indicating that hole collection is the limiting factor in the total charge collection process. The photocurrent profile along the single SnO2 nanowire can decide the diffusion length of electrons and holes.

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