13.78567 六、發明說明： 【發明所屬之技術領域】 本發明係關於-種太陽能電池，尤其係關於—種藉由增進半導體 •薄膜_光吸收率而提昇光電轉換效率之薄膜太陽能電池。 【先前技術】 太陽能電池係為-種利用光伏特效應㈣说㈣恤effect)轉換入射光子 的能量而產生輸出電壓之光電轉換裝置，由於其具有光源之取用不會耗竭、 潔淨、環保以及安全等諸多優點，已成為目前備受矚目之替代能源。太陽能 籲電池依其材料、製造程序與結構之差異可區分為單晶石夕(c轉胞喝、多晶 ^_yoyStallheSi)、非晶矽(Am〇lphousSi)、非石夕料體以及薄膜太陽能電 “池(thinfilmsdarceU)等’其中薄膜太陽能電池的開發，使得製造成本降低 -的同時’亦提高電池轉換效率。 習知以非晶料主之細太陽能電池的基本結射分為透明基板 (substrate)、透明導電層、由p_i_N二極體構成之半導體薄膜層以及電極層四 個主要。p分，並藉由自透明基板一侧入射之光源，於薄膜半導體層内產生電 子-電洞對’ *生成光電流，其中p_i_N、结構一般_氫化非晶石夕咖〇咖仍 φ Silicon, a-Si.H)作為本質層，再藉由原子摻雜①叩㈣方式引進額外中間能 ▼使導▼與價帶的㉟階相互輕合(overlap)，目前為了增加薄駄陽能電池 .的轉換放率’亦可採用微晶石夕(microcrysatline silicon, c-Si:H)材質作為本質層 來進行摻雜並與非晶矽材質進行相互堆疊。 、 、 對於薄膜太陽能電池而言’其光電轉換效能的優劣，大部分取決 於半導體薄膜層對光能吸收之效率，此關鍵因子可決定太陽能電鱗出 的電流與電壓。光源進入物體之型式可為直接(direct)射入或先經過地表其他 物體再散射並擴散(diffilse)該光線，一般的情況，直接陽光約佔太陽能電池入 3 射光的80%，但此部份之光程路徑較短且吸收不易，導致半導體薄膜層之光 .此吸收效率不彰以及增加未吸收光的損失，此外，不論是採用氫化非晶 =或微晶矽所形成的P_i_N結構，其所能提高的光電轉換效率仍然有限。雖然 薄膜太陽能電池中之金屬電極層係具有反射光線之效用，並可將光損 失。卩伤再反射至薄膜半導體層，促使該層之光源再吸收，但其對增 進光電轉換率之效益並不大。 為解決光電轉換效能不佳之問題，先前技術提出使用多層p_i_m構相互 堆登，例如以氫化非晶矽p_i_N結構和微晶矽p_i_N結構相互堆疊而形成太陽能 •電池，藉以提高薄膜太陽能電池的光吸收性與光電轉換效_，然此種堆疊式 結構容易使光穿透率降低’反而降低_太陽能電池的光吸·與光電轉換 效率，另一方面，亦有習知技術於透明基板入射光源該側之表面增設紋理 -(texture)或粗縫化該表面，欲造成光源散射，使光以較多的角度進入薄 膜太陽能電池中，進而增加光與半導體薄膜層相互作用的路徑，然而 該些先前技術可提昇之光電轉換效率仍然有限，且此能量轉換效率 問題係為目前太陽能電池的近__步推廣和普及率之—大瓶頸。 因此，為使光電轉換率可有效提昇，開發一種可增進半導體薄膜 擊層之光能吸收率的薄膜太陽能電池係為當務之急。 【發明内容】 為解決習知薄膜太陽能電池之光電轉換效率不佳的問題，本發 明係提供-種薄膜太陽能電池，其係利用可產生光全反射❿二 intemalreflection)作用以及光反射作用之材料層的設置以增進半導體 薄膜層之光能吸收率，進而達到有效提昇光電轉換率之目的。 為達上述目的，本發明係提供一種薄膜太陽能電池 一基板、一透明導電層、一第一半導體薄膜層、一反射薄膜層 ^其包含： 、一反射率 板之上’且第電== :增，反_層，該反射薄膜層‘== 層之上，該反射構層峨於該反射薄膜 體，係分別具有至少單接面一以上，、例二： 缝·細岭三接_e•細㈣或多接面 ，、中’咖_係形成於低折射率層之上，且該些微通道係延伸開 设至反射率增越· ’藉贿人射光可私_太電池崎，此些 微通道係於反射率增進結構層成膜時預留切割槽所形成。另一方面， 射率層亦可形成於高折射率層之上。 _ 此外，透明導電層、低折射率層與高折射率層係一透明導電氧薄膜 conducting oxide，TCO)層’該透明導電氧薄膜層之材質係選自於 由二氧化錫(Sn02)、氧化銦錫(IT0)、氧化銦鋅剛、氧化鋁鋅(AZ〇)、氧化 鎵鋅(GZO)、氧化鋅(Zn0)以及氧化石夕(Si〇2)所組成“群。反射薄膜層係不 透光之導電材質例如金屬、非金屬(如石墨)或非金屬與金屬組成之混合物 等。第-半導體薄膜層之能隙大於第二半導體薄膜層之能隙，射，第一 半導體薄膜層係由非晶矽(麵抽· silic〇n，a_Si)材質所構成的一 p i_N結 構’第二半導體薄膜層係由微晶石夕(micr〇ciystaUine silic〇n，mcSi)或微晶石夕錯 1178567 (microcrysatlline silicon germanium; mc-SiGe)材質所構成的一 p_i_N 結構。基 板係選自由玻璃、石英、透明塑膠以及透明可撓性基版所組成群組中之任 何一種材料。該電極層係包含至少一金屬層，此金屬層之材料係選自由鋁、 鎳、金、銀、鉻、鈦以及纪所組成之群組。 藉由反射率增進結漏之設置，可使人射触具練高折解之高折 射率層進入具有較低折射率之低折射率層時，產生光之全反射作用，使入 射光再進入第一半導體薄膜層或第二半導體薄膜層，增進該兩半導體薄膜 層之光再吸收；另-方面’利用不透明之反射薄膜層可使光反射至第一半 鲁導體薄膜層，增進第一半導體薄膜層之光吸收率。 前述薄膜太陽能電池係利用具有不同折射率堆疊層之反射率增 進結構層賴光纽射作用錢_反㈣之献射仙，將已通^ 第-半導體_層或第二半導體_層卻未被吸收之級再將至該兩半 導體薄膜射’藉明長光於該兩料體_勒行走的職，促使未吸 收光於該層之再魏，姐提高料輯膜層之光吸收率，進而增進光電 轉換效率，同時改進習知薄膜太陽能電池因堆疊式結構而降低光穿透 率以及級表面設置紋理或祕化處理，卻無法有效提昇薄膜规能電的光 吸^先電轉換效率之弊端，並帶動薄獏太陽_也之推廣應用和促 進使用普及率。 配合圖歧-錢明本翻的實财式，下述所列舉的 明本發明，並非用以限定本發明之範圍，任何熟習 因 不脫縣發日把精朴，當可做錢更動與潤 飾’因此本科之賴當視_之中料鄕_界定 【實施方式】 6 1378567 請參閱第=圖，該圖係本發明薄膜太陽能電池之一較佳實施例 的剖視圖。該薄膜太陽能電池1〇〇係包含一基板11〇、—透明導電 層120、-第-半導體薄膜層13〇、一反射薄膜層14〇、一反射率增 進結構層150、-帛二半導體薄膜層16〇以及一電極層17〇,其中反 射率增進結構層150可使入射光產生全反射作用並將光反射至第二半 導體薄膜層160,進而增進第二半導體薄膜層16〇之光再吸收；另一方面， 反射薄膜層H0可使光反射至第一半導體薄膜層13〇，增進第一半導體薄 膜層130之光吸收率。藉由反射薄膜層14〇與反射率增進結構層 鲁之设置，可有效提昇薄膜太陽能電池100之光電轉換率。 基板110,其一面係為光入射面，基板110之材質係選自由玻璃、 •石英、透明塑勝以及透明可撓性基版所組成群組中之任何一種材料但不 以此為限，凡是可透光材質皆可應用於此，藉以使入射光可進入薄膜 太陽能電池100内。 透明導電層120，其係形成於基板11〇另一面之上，透明導電 層120係為透明導電氧薄膜(transparent conducting oxide，TCO)層，並兼具 高可見光透光性與低阻抗值’其材質係可選自於由二氧化錫(Sn〇2)、氧 •化銦錫(ΐτο)、氧化銦鋅(izo)、氧化鋁鋅(AZ0)、氧化嫁辞(GZ〇)、氧化辞 以及氧化矽(Si02)所組成之族群。 • 第一半導體薄膜層130，其係形成於透明導電層120之上，並 具有至少單接面(junction)以上，例如單接面(如批-細比⑽、雙接面 (double-junction)、二接面(triple-junction)或多接面(multi-junction)。於本發 明實施例中第一半導體薄膜層130之能隙大於第二半導體薄膜層16〇 之月b隙’第一半導體薄膜層13 0係由非晶石夕(ajyjojphous siHcon，a_si)材質 7 1378567 所構成的-P+N轉’齡產絲轉效細賊電子電崎，提供光電 流。 反射薄膜層140，其係形成於透明導電層12〇之上其係為不 透光之導電材質例如金屬、非金屬(如石墨)或非金屬與金屬組成之混合物 等’並具高反射特性’因此當通過第一半導體薄膜層13〇卻未被其吸 收之入射光行經反射薄膜層140時，反射薄膜層14〇可導引入射光反 射至第-半導體薄膜層no,促使第—半導體_層m之光再吸 收作用。此外’由於反㈣膜層⑽係為不透光，故可於此層開設 複數個微通道141 ’以供入射光進入設置於反射薄膜層14〇 :方之 其他層體中，該些微通道141係於該反射薄膜層140成獏時預留切割槽 所形成，藉以使薄臈太陽能電池1〇〇製程中減少一道雷射切割程序。曰 反射率增進結構層150，其係形成於反射薄膜層14〇之上，並包 含至少-堆疊層，該堆疊層係包括—低折射率層151與—高折射率層 152 ’低折射率層151的折射率(refractive index，…係相對低於高折射率 層152之折射率，且高折射率層152係形成於低折射率層151之上，當通 過第二半導體薄膜層160卻未被其吸收之入射光自電極層17〇反射至 反射率增進結構層150時，由於入射光係由高折射率層152進入低折 射率層151，亦即光係由具有高折射率之介質進入具有低折射率之介質， 因此產生光之全反射作用，而此反射光會進入第二半導體薄膜声 160，促使第一半導體薄膜層160之光再吸收作用。此外，前述^置 於反射薄膜層140之複數個微通道141係可延伸開設至反射率增進钟 構層150，且該些微通道係可於反射率增進結構層15〇成膜時預留切割^ 而形成，藉以使薄膜太陽能電池10〇製程中減少一道雷射切割程序。曰 8 152 ΓΑΖΟ、〜u 2)、氣化姻錫_)、氧化姻鋅_)、氧化鋁鋅 於此以及氧化哪ί〇2)所組成之族群，由 將該些透‘電 — ^Γ 之折射率，或可糊不同製程條件 質使透雷^ 折醉避至所需範_，例如加入其他物 _+主$ 1舰材f具有不同折射率，因此可依兩材糊相對高低 ==r折射率層151與高折射率層152的材質，亦即= 射率之材^低折轉之材料配縣—堆疊層，其巾具有相對高折 率層152，具有姉低折卿之材_作為低折射 ί ^ ,料’反射率增進結構層15G所具切刚_數可根據 賴场錢池KK)之光電轉換效能的提昇程度而再麟，並不以此 為限。 第一半導體薄膜層16G，其細彡成於反射率增進結構層150之 並’、有至：>、單接面(junction)以上，例如單接面(咖gle j咖ti〇n)、雙接 面(double_j趣ι〇η)、三接面师e j福㈣或多接面_士』_㈣。於本 發明實施例中第二半導體薄膜層湖的能隙小於第—半導體薄膜層^% 之月b隙第—半導體薄膜層1 60係由微晶石夕(miCr〇Cjystalline siHc〇n，mc_Si) 或微晶矽鍺(microciysatUine silic0n gennanium; mc_SiGe)材質所構成的一 P-i-N結構’藉喊絲轉效應郷賴子冑㈣，提供光電流。 電極層170，其係形成於第二半導體薄膜層16〇之上，電極層 170包含至少一金屬層，該金屬層之材料係選自由鋁、鎳、金、銀、鉻、 鈦以及鈀所組成之群組。由於電極層17〇係為金屬材質，因此，通過 第一半導體薄膜層160卻未被其吸收之入射光至電極層ι7〇時，會 1378567 ^極層170本身材質而使入射光再反射至第二半導體薄膜層_反 射率增進結構層15〇。 請參閱第二圖，該圖係本發明薄膜太陽能電池之另一較佳實施 ▲ 列的剖視圖。該薄膜太陽能電池雇之結構大致上與前述實施例之 2太％能電池则相似，且薄膜太陽能電池綱所設各層體之材 二功用俩於_太陽能電池刚。_太陽能電池·係包含 =基板21〇、-透明導電層22〇、一第一半導體薄膜詹⑽、一反射 賴層、一反射率增進結構層25〇、_第二半導體薄膜層細 以及-電極層27G’其中反射率增進結構層25q可使入射光產生全反 射作用並將光反射至第-半導體薄膜層23〇，進而增 230之光再吸收，·另一方面，反㈣膜層可使光反射至第一半導^ =層二增進第一彻薄膜層23〇之光吸收率，同時反射薄_〇 開设有複數個微通道24卜以供入射光進入薄膜太陽能電池細内部。 精由反射_層24G與反射率增進結構層25()之設置，可有效提 薄膜太陽能電池200之光電轉換率。 其中，反射率增進結構層25〇包含至少一堆疊層， 括-歸射率層251與-高折射率層252，低折射率層251的折射率係^ 對低於南折f率層252之折射率’且低折射率層2M係形成於高折射率層 252之上’當通過第一半導體薄膜層23〇卻未被其吸收之入射光進入 反射率增進結構層250時，由於入射光係由高折射率層252進入低折 射率層25卜亦即光係由具有高折射率之介·人具魏折神之介質， 因此產生光之全反射作用，而此反射光會進人第-半導體薄膜層 230,促使第-半導體薄膜層23〇之光再吸收作用。 、曰 1378567 前述薄膜太陽能電池100或薄膜太陽能電池200之各層體係依 序以習知方法而逐層堆疊形成，該方法可包含減鍍、常壓化學氣相沈 積、低壓化學氣相沈積、電子迴旋共振法、直流輝光放電法、射頻輝光放電 法、满:謝法和熱絲法等，但不以此為限，凡是可於一層體之上形成另一層體 的方法皆可應用於此。 請參閱第三圖，該圖係本發明薄膜太陽能電池之一較佳實施例 的入射光產生反射與全反射之示意圖。當入射光由基板11()進入薄 膜太陽能電池100内，會依序通過透明導電層120與第一半導體薄 籲膜層130’並行至反射薄膜層140,此時不透明之反射薄膜層14〇 可使入射光反射至第一半導體薄膜層13 〇(光反射路徑請參閱第三圖粗黑 '色箭頭處)’促使第一半導體薄膜層130之光再吸收作用；另一方面， -由於反射薄膜層14〇係設置有複數個微通道141，藉以使入射光通 過該些微通道141進入反射率增進結構層15〇,再進入至第二半導 體薄膜層160，而此些微通道141亦可延伸開設至反射率增進結構 層150，使入射光通過該些微通道141直接進入第二半導體薄膜層 160。最後入射光行至金屬製電極層170處，會自電極層17〇反射至反 鲁射率增進結構層150’並藉由入射光由高折射率層152進入低折射率層 151產生之光全反射(光全反射路徑請參閱第三圖粗白色箭頭處），而反射至 第二半導體薄膜層160，促使第二半導體薄膜層16〇之光再吸收作 用。 請參閱第四圖，該圖係本發明薄膜太陽能電池之另一較佳實施 例的入射光產生反射與全反射之示意圖。當入射光由基板21〇進入 薄膜太陽能電池200内，會依序通過透明導電層22〇與第一半導體 薄膜層230 ’並行至反射薄膜層240 ’ j：匕時不透明之反射薄膜層24〇 1378567 可使入射光反射至第一半導體薄膜層230(光反射路徑請參閱第四圖粗黑 色箭頭處）’促使第一半導體薄膜層230之光再吸收作用；另一方面， 由於反射薄膜層240係設置有複數個微通道241，藉以使入射光可 通過該些微通道241進入反射率增進結構層250，並利用入射光由 高折射率層252進入低折射率層251產生之光全反射(光全反射路徑請參閱 第四圖粗白色箭頭處），而反射至第一半導體薄膜層23〇，促使第一半導 體薄膜層230之光再吸收作用。 綜上所述’藉由反射率增進結構層15〇、25〇之設置，可使入射光產生 雄光之全反射作用，使入射光再進入第一半導體薄膜層13〇、23〇或第二半導 體薄膜層160、260 ’增進該兩半導體薄膜層之光吸收率；另一方面，利用 -不透明之反射薄膜層140、240可使光反射至第一半導體薄膜層13〇、23〇， -增進第-半導體薄膜層130、230之光吸收率，進而有效提昇薄膜太陽能電 池100、200之光電轉換效率。 【圖式簡單說明】 第-圖係本發明㈣太陽能電池之-齡實齡丨的剔視圖。 籲第一圖係本發明薄社陽能電池之另—較佳實施例的剖視圖。 第二圖係本發明溥膜太陽能電池之一較佳實施例的入射光產生反射 與全反射之示意圖。 第四圖係本發明薄膜太陽能電池之另—較佳實施例的入射光產生反 射與全反射之示意圖。 12 1378567 【主要元件符號說明】 100 薄膜太陽能電池 110 基板 • 120 透明導電層 130 第一半導體薄膜層 140 反射薄膜層 141 微通道 150 反射率增進結構層 • 151 低折射率層 160 第二半導體薄膜層 - 170 電極層 -200 薄膜太陽能電池 210 基板 220 透明導電層 230 第一半導體薄膜層 240 反射薄膜層 • 241微通道 250 反射率增進結構層 251 低折射率層 260 第二半導體薄膜層 270 電極層 152 高折射率層 252 高折射率層 1313.78567 VI. Description of the Invention: [Technical Field] The present invention relates to a solar cell, and more particularly to a thin film solar cell which improves photoelectric conversion efficiency by enhancing semiconductor/film absorption rate. [Prior Art] A solar cell is a photoelectric conversion device that converts the energy of an incident photon to produce an output voltage by using a photovoltaic effect (fourth). Since it has a light source, it is not exhausted, clean, environmentally friendly, and safe. Many advantages have become the most important alternative energy source. According to the differences in materials, manufacturing procedures and structures, solar energy batteries can be distinguished into single crystal stone (c-transfer, polycrystalline ^_yoyStallheSi), amorphous germanium (Am〇lphousSi), non-stone material and thin film solar power. "ThinfilmsdarceU" and the like, in which the development of thin-film solar cells, the manufacturing cost is reduced - while also improving the battery conversion efficiency. It is known that the basic emission of a thin solar cell of a thin material is divided into a transparent substrate (substrate). a transparent conductive layer, a semiconductor thin film layer composed of a p_i_N diode, and an electrode layer of four main p points, and an electron-hole pair is generated in the thin film semiconductor layer by a light source incident from one side of the transparent substrate. The photocurrent is generated, wherein p_i_N, the structure is generally _hydrogenated amorphous 夕 夕 , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , , It is overlapped with the 35th order of the valence band. At present, in order to increase the conversion rate of the thin solar cell, the microcrysatline silicon (c-Si:H) material can also be used as the intrinsic layer for doping. and Amorphous germanium materials are stacked on top of each other. For thin-film solar cells, the quality of their photoelectric conversion performance depends mostly on the efficiency of light absorption by the semiconductor thin film layer. This key factor determines the current and current of the solar scale. Voltage. The type of light source entering the object can be direct injection or first diffuse and diffuse the light through other objects on the surface. In general, direct sunlight accounts for about 80% of the solar light entering the solar cell, but this Part of the optical path is short and absorption is not easy, resulting in light in the semiconductor film layer. This absorption efficiency is not good and the loss of unabsorbed light is increased. In addition, the P_i_N structure formed by hydrogenation amorphous or microcrystalline germanium is used. The photoelectric conversion efficiency that can be improved is still limited. Although the metal electrode layer in the thin film solar cell has the effect of reflecting light, and can lose light, the flaw is reflected back to the thin film semiconductor layer, and the light source of the layer is reabsorbed. However, its effectiveness in improving the photoelectric conversion rate is not large. To solve the problem of poor photoelectric conversion performance, the prior art proposes Multilayer p_i_m structure is stacked on each other, for example, a hydrogenated amorphous 矽p_i_N structure and a microcrystalline 矽p_i_N structure are stacked on each other to form a solar cell, thereby improving the light absorption and photoelectric conversion effect of the thin film solar cell. The structure is easy to reduce the light transmittance, and instead reduces the light absorption and photoelectric conversion efficiency of the solar cell. On the other hand, there is a conventional technique of adding texture to the surface of the side of the transparent substrate incident light source. The surface is etched to cause light to scatter, allowing light to enter the thin film solar cell at a greater angle, thereby increasing the path of interaction between the light and the semiconductor thin film layer. However, the photoelectric conversion efficiency of the prior art can be improved, and this The energy conversion efficiency problem is a big bottleneck in the current promotion and popularization rate of solar cells. Therefore, in order to effectively increase the photoelectric conversion rate, it is an urgent task to develop a thin film solar cell system which can enhance the light energy absorption rate of a semiconductor film layer. SUMMARY OF THE INVENTION In order to solve the problem of poor photoelectric conversion efficiency of a conventional thin film solar cell, the present invention provides a thin film solar cell which utilizes a material layer capable of generating a total reflection of light and a light reflection effect. The arrangement is to enhance the light energy absorption rate of the semiconductor film layer, thereby achieving the purpose of effectively increasing the photoelectric conversion rate. To achieve the above objective, the present invention provides a substrate for a thin film solar cell, a transparent conductive layer, a first semiconductor thin film layer, and a reflective thin film layer comprising: a reflective plate above and a first electric ==: Adding, anti-layer, the reflective film layer '== above the layer, the reflective layer is attached to the reflective film body, each having at least a single junction or more, and example 2: slit, fine ridge, _e • Fine (four) or multiple junctions, the middle 'coffee' is formed on the low refractive index layer, and the microchannels are extended to increase the reflectivity. The microchannels are formed by leaving a cutting groove when the reflectivity enhancing structure layer is formed. On the other hand, the luminosity layer may also be formed on the high refractive index layer. Further, the transparent conductive layer, the low refractive index layer and the high refractive index layer are a transparent conductive oxygen film conducting oxide (TCO) layer. The material of the transparent conductive oxygen thin film layer is selected from the group consisting of tin dioxide (Sn02), oxidation. Indium tin (IT0), indium zinc oxide, aluminum zinc oxide (AZ〇), gallium zinc oxide (GZO), zinc oxide (Zn0), and oxidized stone (Si〇2) are composed of “groups. Reflective film layers are not a light-transmissive conductive material such as a metal, a non-metal (such as graphite) or a mixture of a non-metal and a metal, etc. The energy gap of the first semiconductor thin film layer is larger than the energy gap of the second semiconductor thin film layer, and the first semiconductor thin film layer A p i_N structure consisting of amorphous germanium (silic〇n, a_Si) material, the second semiconductor thin film layer is composed of microcrystalline mics, mic, or microcrystalline 1178567 (microcrysatlline silicon germanium; mc-SiGe) material consists of a p_i_N structure. The substrate is selected from any group consisting of glass, quartz, transparent plastic and transparent flexible substrates. At least one metal layer, the metal layer The material is selected from the group consisting of aluminum, nickel, gold, silver, chromium, titanium, and Ji. By increasing the junction leakage by the reflectance, the high refractive index layer of the human lens can be highly plied into When the low refractive index layer of the lower refractive index is generated, total reflection of light is generated to re-enter the incident light into the first semiconductor film layer or the second semiconductor film layer to enhance light re-absorption of the two semiconductor film layers; The opaque reflective film layer is used to reflect light to the first semi-luconductive film layer to improve the light absorptivity of the first semiconductor film layer. The thin film solar cell utilizes a reflectivity enhancement structure layer having a different refractive index stack layer. The new shot of the money _ anti (four) of the singer, will pass the first - semiconductor _ layer or the second semiconductor _ layer but not absorbed the level and then the two semiconductor film shots The position of the body is to promote the absorption of light in the layer. The sister enhances the light absorption rate of the film layer, thereby improving the photoelectric conversion efficiency, and at the same time improving the conventional thin film solar cell to reduce the light penetration due to the stacked structure. Rate and level surface setting texture or secret treatment, but can not effectively improve the drawbacks of the film-powered light-absorbing power conversion efficiency, and drive the thin sun _ also promote the application and promote the use of penetration rate. The invention of the present invention is not limited to the scope of the present invention. Any familiarity is not simple. < Descrição _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ _ 11〇, a transparent conductive layer 120, a first semiconductor thin film layer 13A, a reflective thin film layer 14A, a reflectivity enhancing structural layer 150, a second semiconductor thin film layer 16A, and an electrode layer 17〇, wherein the reflection The rate-increasing structure layer 150 can cause the total reflection of the incident light and reflect the light to the second semiconductor film layer 160, thereby enhancing the light re-absorption of the second semiconductor film layer 16; on the other hand, the reflective film layer H0 can make the light 13〇 emitted to the thin film layer of the first semiconductor, the first semiconductor thin film layer enhancing the light absorption rate of 130. The photoelectric conversion rate of the thin film solar cell 100 can be effectively improved by the arrangement of the reflective film layer 14 and the reflectivity enhancing structure layer. The substrate 110 has one surface as a light incident surface, and the material of the substrate 110 is selected from any group consisting of glass, quartz, transparent plastic and transparent flexible substrates, but not limited thereto. A light transmissive material can be applied thereto so that incident light can enter the thin film solar cell 100. The transparent conductive layer 120 is formed on the other side of the substrate 11. The transparent conductive layer 120 is a transparent conducting oxide (TCO) layer and has high visible light transmittance and low impedance value. The material may be selected from the group consisting of tin dioxide (Sn〇2), indium tin oxide (ΐτο), indium zinc oxide (izo), aluminum zinc oxide (AZ0), oxidized singularity (GZ〇), oxidized words, and A group of cerium oxide (Si02). • a first semiconductor thin film layer 130 formed on the transparent conductive layer 120 and having at least a single junction, such as a single junction (eg, batch-to-fine ratio (10), double-junction) a triple-junction or a multi-junction. In the embodiment of the invention, the energy gap of the first semiconductor thin film layer 130 is greater than the second semiconductor thin film layer 16 The film layer 130 is a -P+N to 'age-generation wire-transforming fine thief electronic electric yaki, which is composed of amorphous austenite (aj_jojhous siHcon, a_si) material 7 1378567, and provides a photocurrent. The reflective film layer 140 is a system Formed on the transparent conductive layer 12A, it is an opaque conductive material such as metal, non-metal (such as graphite) or a mixture of non-metal and metal, and has high reflection characteristics. Therefore, when passing through the first semiconductor film When the incident light that is not absorbed by the layer 13 passes through the reflective film layer 140, the reflective film layer 14 can guide the incident light to be reflected to the first semiconductor thin film layer no, thereby promoting the light reabsorption of the first semiconductor layer m. In addition, 'because the anti-(four) film layer (10) is opaque, A plurality of microchannels 141' may be opened in the layer for incident light to enter the other layer body disposed on the reflective film layer 14: the microchannels 141 are reserved for the cutting groove when the reflective film layer 140 is formed into a crucible Forming, thereby reducing a laser cutting process in the thin tan solar cell 1 〇〇 process. The 曰 reflectivity enhancing structure layer 150 is formed on the reflective film layer 14 , and comprises at least a stacked layer, the stacked layer The refractive index of the low refractive index layer 151 and the low refractive index layer 151 is lower than the refractive index of the high refractive index layer 152, and the high refractive index layer 152 is formed. Above the low refractive index layer 151, when incident light that is not absorbed by the second semiconductor thin film layer 160 is reflected from the electrode layer 17 to the reflectance enhancing structure layer 150, since the incident light is from the high refractive index layer 152 Entering the low refractive index layer 151, that is, the light system enters a medium having a low refractive index from a medium having a high refractive index, thereby generating a total reflection of light, and the reflected light enters the second semiconductor film sound 160, prompting the first The light re-absorption of the conductive film layer 160. Further, the plurality of microchannels 141 disposed on the reflective film layer 140 may extend to the reflectivity enhancing clock layer 150, and the microchannels may be used in the reflectivity enhancing structure. The layer 15 is formed when the film is formed into a film, thereby reducing a laser cutting process in the thin film solar cell 10 曰 process. 曰8 152 ΓΑΖΟ, 〜u 2), gasification yin _), oxidized zinc _ ), the group consisting of aluminum oxide zinc and oxidized 2), by which the refractive index of the 'Electrical-^Γ, or the different process conditions can be used to make the lightning Fan_, for example, adding other materials_+main$1 ship material f has different refractive indexes, so the material of the two refractive layers can be relatively high and low == r refractive index layer 151 and high refractive index layer 152, that is, = rate Material ^ low-fold material with county - stacked layer, its towel has a relatively high-profile layer 152, with a low-definition material _ as a low-refraction ί ^, material 'reflectivity enhancement structural layer 15G has just cut _ The number can be re-arranged according to the degree of improvement of the photoelectric conversion performance of Laichang Qianchi KK). . The first semiconductor thin film layer 16G is finely formed in the reflectivity enhancing structure layer 150, has a >, a single junction or more, for example, a single junction (cafe) Double junction (double_j fun ι〇η), three joint teacher ej Fu (four) or multiple junction _ _ _ _ (four). In the embodiment of the present invention, the energy gap of the second semiconductor thin film layer lake is smaller than that of the first semiconductor thin film layer, and the semiconductor thin film layer 1 is a microcrystalline stone (miCr〇Cjystalline siHc〇n, mc_Si) Or a micro-pyrene (microcyysatUine silic0n gennanium; mc_SiGe) material consists of a PiN structure 'by the wire-turn effect 郷 胄 胄 (four), providing photocurrent. The electrode layer 170 is formed on the second semiconductor film layer 16B, and the electrode layer 170 comprises at least one metal layer, the material of the metal layer is selected from the group consisting of aluminum, nickel, gold, silver, chromium, titanium and palladium. Group of. Since the electrode layer 17 is made of a metal material, when the first semiconductor thin film layer 160 is not absorbed by the incident light to the electrode layer ι7 ,, the material of the layer 1378567 is electrically reflected to reflect the incident light. Two semiconductor thin film layers _ reflectivity enhancing structural layer 15 〇. Please refer to the second drawing, which is a cross-sectional view of another preferred embodiment of the thin film solar cell of the present invention. The structure of the thin film solar cell is substantially similar to that of the above-mentioned embodiment, and the thin film solar cell is provided with two layers of materials. _ solar cell includes: substrate 21 〇, - transparent conductive layer 22 〇, a first semiconductor film (10), a reflective layer, a reflectivity enhancing structure layer 25 〇, a second semiconductor film layer thin and - electrode The layer 27G' wherein the reflectance enhancing structure layer 25q can totally reflect the incident light and reflect the light to the first semiconductor thin film layer 23, thereby increasing the light of 230 to reabsorb, and on the other hand, the anti (four) film layer can The light is reflected to the first semiconductor layer, and the light absorption rate of the first film layer 23 is increased, and the plurality of microchannels 24 are provided for the incident light to enter the thin interior of the thin film solar cell. The arrangement of the reflection layer _ layer 24G and the reflectance enhancement structure layer 25 () can effectively improve the photoelectric conversion ratio of the thin film solar cell 200. The reflectivity enhancing structure layer 25A includes at least one stacked layer including a refracting rate layer 251 and a high refractive index layer 252, and the refractive index of the low refractive index layer 251 is lower than the south folding rate layer 252. The refractive index 'and the low refractive index layer 2M are formed on the high refractive index layer 252' when the incident light that has passed through the first semiconductor thin film layer 23 but is not absorbed therein enters the reflectance enhancing structure layer 250, due to the incident light system The high refractive index layer 252 enters the low refractive index layer 25, that is, the light system is made of a medium having a high refractive index and a human body, thereby generating a total reflection of light, and the reflected light will enter the first- The semiconductor thin film layer 230 promotes light reabsorption of the first semiconductor thin film layer 23.曰1378567 The layer system of the foregoing thin film solar cell 100 or thin film solar cell 200 is sequentially stacked layer by layer by a conventional method, and the method may include deplating, atmospheric pressure chemical vapor deposition, low pressure chemical vapor deposition, electron cyclotron Resonance method, DC glow discharge method, RF glow discharge method, full: Xie method and hot wire method, but not limited to this, any method that can form another layer on one layer can be applied to this. Referring to the third drawing, which is a schematic diagram of incident light generation reflection and total reflection in a preferred embodiment of the thin film solar cell of the present invention. When the incident light enters the thin film solar cell 100 from the substrate 11 (), it will sequentially pass through the transparent conductive layer 120 and the first semiconductor thin film layer 130' to the reflective film layer 140. At this time, the opaque reflective film layer 14 can be Reflecting the incident light to the first semiconductor film layer 13 (the light reflection path is referred to the thick black color arrow of the third figure) 'promotes the light reabsorption of the first semiconductor film layer 130; on the other hand, - due to the reflective film The layer 14 is provided with a plurality of microchannels 141, so that incident light passes through the microchannels 141 into the reflectivity enhancing structure layer 15 and then into the second semiconductor film layer 160, and the microchannels 141 can also be extended to The reflectivity enhancement structure layer 150 allows incident light to pass directly into the second semiconductor film layer 160 through the microchannels 141. Finally, the incident light travels to the metal electrode layer 170, and is reflected from the electrode layer 17〇 to the anti-radiation enhancement structure layer 150' and the light generated by the high refractive index layer 152 entering the low refractive index layer 151 by the incident light is all The reflection (refer to the thick white arrow of the third figure) is reflected to the second semiconductor film layer 160 to promote the light reabsorption of the second semiconductor film layer 16 . Please refer to the fourth figure, which is a schematic diagram showing incident light reflection and total reflection according to another preferred embodiment of the thin film solar cell of the present invention. When the incident light enters the thin film solar cell 200 from the substrate 21, it will sequentially pass through the transparent conductive layer 22 and the first semiconductor thin film layer 230' to the reflective thin film layer 240' j: opaque reflective film layer 24〇1378567 The incident light can be reflected to the first semiconductor thin film layer 230 (refer to the thick black arrow of the fourth figure) to promote the light reabsorption of the first semiconductor thin film layer 230; on the other hand, the reflective thin film layer 240 A plurality of microchannels 241 are provided to allow incident light to enter the reflectivity enhancing structure layer 250 through the microchannels 241, and to utilize the incident light from the high refractive index layer 252 into the low refractive index layer 251 to generate total light reflection (all of the light) The reflection path is referred to the thick white arrow of the fourth figure, and is reflected to the first semiconductor film layer 23, causing the light reabsorption of the first semiconductor film layer 230. In summary, by the reflection enhancement structure layer 15〇, 25〇, the incident light can be made to have a total reflection of the male light, so that the incident light can enter the first semiconductor film layer 13〇, 23〇 or the second. The semiconductor thin film layers 160, 260' enhance the light absorptivity of the two semiconductor thin film layers; on the other hand, the reflective film layers 140, 240 are opaque to reflect light to the first semiconductor thin film layers 13, 23, - The light absorptivity of the first-semiconductor film layers 130, 230, thereby effectively improving the photoelectric conversion efficiency of the thin film solar cells 100, 200. BRIEF DESCRIPTION OF THE DRAWINGS The first figure is a cross-sectional view of a solar cell-age age 丨. BRIEF DESCRIPTION OF THE DRAWINGS The first drawing is a cross-sectional view of another preferred embodiment of the thin solar cell of the present invention. The second figure is a schematic diagram of incident light generation reflection and total reflection in a preferred embodiment of the enamel film solar cell of the present invention. The fourth figure is a schematic diagram showing incident and total reflection of incident light in another preferred embodiment of the thin film solar cell of the present invention. 12 1378567 [Description of main components] 100 thin film solar cell 110 substrate • 120 transparent conductive layer 130 first semiconductor thin film layer 140 reflective thin film layer 141 microchannel 150 reflectivity enhancing structural layer • 151 low refractive index layer 160 second semiconductor thin film layer - 170 Electrode Layer - 200 Thin Film Solar Cell 210 Substrate 220 Transparent Conductive Layer 230 First Semiconductor Thin Film Layer 240 Reflective Thin Film Layer • 241 Microchannel 250 Reflectance Enhancement Structure Layer 251 Low Refractive Index Layer 260 Second Semiconductor Thin Film Layer 270 Electrode Layer 152 High refractive index layer 252 high refractive index layer 13