提昇單晶矽太陽能電池方法有很多種，而本文是利用背面深蝕刻結構去提昇光電流以達到增加太陽電池效率。有別於一般孔洞太陽能電池，我們採用極深蝕刻，並且將此結構運用於背面上。其目的是為了減少載子傳輸距離，因而可以迅速的到達正背面電極而減少復合，並且比平面薄型化的太陽能電池更有較多吸收空間；並且利用深蝕刻斜面達到光在矽內部的反射以拉長光路徑，進而達到吸收更完全；最後由於V型溝槽結構，增加電極和半導體接觸面積而增加載子蒐集能力，以上的三大好處將可以有效的提昇光電流。
首先在(100)的矽晶圓上先蓋上SiNX當hard mask，再用黃光微影技術定義出圖樣，即可用KOH非等向性蝕刻特性，在矽晶圓上蝕刻出V型的長溝，深度為130μm∼140μm、180μm∼190μm、240μm∼245μm。此一研究中，我們發現當孔洞深度為240μm∼245μm最深時，有最佳的短路電流密度，電流有明顯隨著蝕刻深度增加而增加比起平面的太陽能電池參考片(34.066mA/cm2)增加10%，達到37.636mA/cm2，效率也從原來13.095％提昇至14.731％，成長幅度超過11％。和薄片（厚度250μm）效率（14.464％）相比，也有1.8％幅度的成長，更不用說有經過修補缺陷後的深蝕刻太陽能電池（效率超過15％），因此深蝕刻結構是能夠提昇整體效率的。
而我們發現深蝕刻雖然可以有效提昇光電流，但是在蝕刻過程中卻會造成鉀金屬殘留，造成缺陷。所以經由溼式蝕刻去除表面一層，可以達到去除鉀離子殘留的目的。而經由此步驟，lifetime、EQE、效率都能再次提昇。最後因為經過texture和深蝕刻過程，表面會造成斷鍵缺陷，所以再經由passivation去修補進而再次提昇效率，經由以上二步驟方法可以成功的使太陽能電池效率突破15％來到15.3％左右，成長幅度大約4％。
最後未來展望提出背面電極採用網版印刷電極，在RTA燒結下可以再進一步提昇VOC和JSC，但是需要改善製成條件，才能有效的提昇效率。

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