201230357 六、發明說明： 【發明所屬之技術領域】 本發明係關於一種太陽能電池元件，特別關於一種薄 膜太陽能電池元件。 【先前技術】 近幾年由於單晶矽、多晶矽等市場物料缺乏，造成價 格飛漲使得許多矽晶型太陽能電池廠商產能無法上升， 而矽薄膜太陽電池（Silicon Thin-Film Solar Cell)使用玻 螭基板，而鑛矽膜使用矽烧（SiH4)與氫氣（H2)，整體元 件薄膜厚度不過數微米，因此沒有缺料之問題。除此之 外’石夕薄膜太陽電池溫度係數較低，溫度上升時元件開路 電塵降低較緩，其元件效率損失較矽晶型太陽電池少。另 〜方面，照度小於l〇W/m2之低照度情況下’矽薄膜太陽 電池仍能維持在AM1.5照度下之90%，而傳統矽晶型太陽 電池在此情形下僅能維持20%。 相較於一般市佔超過八成之結晶矽太陽電池，矽薄膜 太陽電池擁有價格低廉、溫度效應低等優點，經評估若以 黎年的發電量而言，矽薄膜太陽電池之總體發電量在不同 ^點冒阿於石夕晶型太陽電池5〜25%左右，因此成為現階 ^發展太陽電池之主要重點。 但由於典型矽薄膜太陽電池主體是非晶矽層 (Amorph〇Us Si, a_Si )，在太陽光照射下其薄膜導電率會 爷口而使元件產生光照衰退現象。另一方面，非晶石夕 201230357 薄膜能階約為1.7eV左右，僅能吸收光波長700nm以下光 源，造成元件光電轉換效率偏低。 因此，如何提供一種薄膜太陽能電池元件，能夠抵抗 光照衰退並提升光電轉換效率，已成為重要課題之一。 【發明内容】 有鑑於上述課題，本發明之目的為提供一種能夠抵抗 光照衰退並提升光電轉換效率之薄膜太陽能電池元件。 ^ 為達上述目的，依據本發明之一種薄膜太陽能電池元 件包含一 P型非晶矽層、一 N型非晶矽層以及一微晶矽 層。微晶矽層設置於P型非晶矽層與N型非晶矽層之間。 在一實施例中，微晶矽層可為本質微晶矽層、或P型 ' 微晶矽層、或N型微晶矽層。 • 在一實施例中，薄膜太陽能電池元件更包含一本質非 晶矽層，其設置於該P型非晶矽層與微晶矽層之間、或設 置於N型非晶矽層與微晶矽層之間。本質非晶矽層可作用 • 電子電洞復合的阻擋層，進而提升光電轉換效率。 在一實施例中，P型非晶矽層、或N型非晶矽層、或 本質非晶矽層係摻雜元素表中皿A至V A族之其中至少一 元素。例如，非晶矽的各層可以做成非晶鍺化矽（a-SiGe:H) 層，其中可以調整鍺的含量以改變非晶鍺化矽（a-SiGe:H) 層的能階，使其與埋入之微晶矽層能有更好之能階匹配以 進一步增加光電轉換效率。 承上所述，本發明在非晶矽薄膜太陽能電池中設置一 201230357 微晶石夕層。相較於非石夕晶層 光線而彌補非矽晶之不足，、a曰矽層可吸收較長波長之 如，微晶石夕能階約為i leV T提升電池轉換效率；例 一將可有效彌補非晶發:==圍為5。。〜 電池之轉換效率。此外，$先波長進而增加 較佳之光照衰退抵抗能力，而提升^曰，微晶石夕層具有 藉由在非晶石夕薄膜太陽能電池中能。並且本發明 非晶矽層的厚声，造而D又置彳政晶矽層，可減少 於元件之各尽Γ 低光照衰退現象。此外，由 =兀件之各層都可以在麵基板上 常適合現有㈣膜太陽電池產業引用直接;:積“’非 【實施方式】 式，說明依本發明較佳實施例之一 ，其中相同的元件將以相同的參照 以下將參照相關圖 種薄膜太陽能電池元件 符號加以說明。 圖立 1為本發明第—實施例之—種薄膜太陽能電池元件 、不思圖。如圖1所示，薄膜太陽能電池元件i包含一 P型非日a碎層（P_type a_Si: H ) i i、— N型非晶石夕層（N. a-Si · Η) 12以及一微晶矽層（，Si : H) i3。微晶矽層 13設置於P型非晶石夕層11|%N型非晶石夕層12之間。 其中，P型非晶矽層11可例如以射頻式電漿輔助化學 氣相沈積方法（Radi〇 Frequency Plasma Enhancement201230357 VI. Description of the Invention: [Technical Field] The present invention relates to a solar cell element, and more particularly to a thin film solar cell element. [Prior Art] In recent years, due to the lack of market materials such as single crystal germanium and polycrystalline germanium, the price soaring has made many wafer solar cell manufacturers unable to increase their production capacity, while the Silicon Thin-Film Solar Cell uses a glass substrate. While the ore film uses bismuth (SiH4) and hydrogen (H2), the thickness of the overall component film is only a few micrometers, so there is no shortage of material. In addition, the temperature coefficient of the Shixi thin film solar cell is low. When the temperature rises, the open circuit of the component is reduced, and the component efficiency loss is less than that of the twin crystal solar cell. On the other hand, in the case of low illumination with illumination less than l〇W/m2, the silicon solar cell can still maintain 90% of the AM1.5 illumination, while the conventional twin solar cell can only maintain 20% in this case. . Compared with the general market, which accounts for more than 80% of the crystalline solar cells, the thin-film solar cells have the advantages of low price and low temperature effect. It is estimated that the total power generation of the thin-film solar cells is different in terms of the power generation of the Li-Year. ^The point is about 5~25% of the solar cell of Ashi Shixi crystal, so it has become the main focus of the development of solar cells. However, since the main body of the typical tantalum thin film solar cell is an amorphous layer (Amorph〇Us Si, a_Si), the conductivity of the film under the irradiation of sunlight will cause the light to decay. On the other hand, Amorphous Shixia 201230357 has a film energy level of about 1.7 eV, and can only absorb light sources with a wavelength of 700 nm or less, resulting in low photoelectric conversion efficiency of components. Therefore, how to provide a thin film solar cell element, which is resistant to light degradation and enhance photoelectric conversion efficiency, has become one of the important topics. SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to provide a thin film solar cell element which is resistant to light deterioration and enhances photoelectric conversion efficiency. To achieve the above object, a thin film solar cell element according to the present invention comprises a P-type amorphous germanium layer, an N-type amorphous germanium layer and a microcrystalline germanium layer. The microcrystalline germanium layer is disposed between the P-type amorphous germanium layer and the N-type amorphous germanium layer. In one embodiment, the microcrystalline germanium layer can be an intrinsic microcrystalline germanium layer, or a P-type microcrystalline germanium layer, or an N-type microcrystalline germanium layer. In an embodiment, the thin film solar cell component further comprises an intrinsic amorphous germanium layer disposed between the P-type amorphous germanium layer and the microcrystalline germanium layer, or disposed in the N-type amorphous germanium layer and the microcrystal Between the layers. The intrinsic amorphous layer can act • The electron hole composite barrier layer, which in turn improves the photoelectric conversion efficiency. In one embodiment, the P-type amorphous germanium layer, or the N-type amorphous germanium layer, or the intrinsic amorphous germanium layer is at least one element of the group A to V A in the doping element table. For example, the layers of the amorphous germanium may be formed as an amorphous germanium telluride (a-SiGe:H) layer in which the germanium content may be adjusted to change the energy level of the amorphous germanium telluride (a-SiGe:H) layer. It has better energy level matching with the buried microcrystalline germanium layer to further increase the photoelectric conversion efficiency. As described above, the present invention provides a 201230357 microcrystalline layer in an amorphous germanium thin film solar cell. Compared with the non-Shi Xi layer light to compensate for the lack of non-crystal, a layer can absorb longer wavelengths, such as micro-laser energy level is about i leV T to improve battery conversion efficiency; Effectively compensate for amorphous hair: == around 5. . ~ Battery conversion efficiency. In addition, the first wavelength further increases the resistance to light decay, and the microcrystalline layer is enhanced by the amorphous silicon solar cell. Moreover, the thick sound of the amorphous germanium layer of the invention can be reduced by the low-light decay phenomenon of the components. In addition, each layer of the component can be directly adapted to the existing (four) film solar cell industry on the surface substrate; the product is not described in the preferred embodiment of the present invention, wherein the same The elements will be described with reference to the related drawings of the thin film solar cell elements under the same reference. Fig. 1 is a thin film solar cell element according to the first embodiment of the present invention, as shown in Fig. 1, thin film solar energy The battery element i includes a P-type non-day a fragment (P_type a_Si: H) ii, an N-type amorphous layer (N. a-Si · Η) 12, and a microcrystalline layer (Si: H) I3. The microcrystalline germanium layer 13 is disposed between the P-type amorphous slab layer 11|%N-type amorphous slab layer 12. The P-type amorphous germanium layer 11 can be, for example, a radio frequency plasma-assisted chemical vapor phase. Deposition method (Radi〇Frequency Plasma Enhancement
Chemical Vap0r Dep0Siti0n，RF_PECVI))而形成，並通入 矽烷（SiHO與氫氣（¾)以及作為摻雜（d〇ping)氣體 201230357 的B2H6 ’沈積p-type之氫化非晶矽（Hydrogenated Amorphous Silicon，a_Si : H)薄膜。製程上例如，設定基 板溫度約為150〜300。(：，腔體壓力為〇丨〜丨化^，沈積速 率約為0.1〜0.3nm/s，薄膜厚度約為1〇賺，能階約為17 〜1.8eV。若增加通入甲燒後，p型非晶矽層丨丨之能階可 . 到 2eV。 N型非晶"^層12之製程可類似P型非晶碎層U。其 中，N型非晶矽層12可以RF_pECVD通入矽烷與氫氣， 以及作為摻雜_ PH3,沈積η.之氫化非晶矽 (a-Si . H)薄膜。製程上例如，設定基板溫度約為丨5〇〜 300C月工月丑壓力為〇1〜，沈積速率約為〜 0.3nm/s薄版厚度約為1〇麵，能階約為。Chemical Vap0r Dep0Siti0n, RF_PECVI)), and is introduced into decane (SiHO and hydrogen (3⁄4) and as a doping (d〇ping) gas 201230357 B2H6 'deposited p-type hydrogenated amorphous 矽 (Hydrogenated Amorphous Silicon, a_Si) : H) film. For example, set the substrate temperature to about 150~300. (:, the cavity pressure is 〇丨~丨化^, the deposition rate is about 0.1~0.3nm/s, and the film thickness is about 1〇. The energy level is about 17~1.8eV. If the addition of A-burning is added, the energy level of the p-type amorphous germanium layer can be up to 2eV. The process of N-type amorphous "^ layer 12 can be similar to P-type non- The crystal layer U. wherein the N-type amorphous germanium layer 12 can be fused with decane and hydrogen by RF_pECVD, and a hydrogenated amorphous germanium (a-Si.H) film deposited as doping_PH3, for example, on the process. Set the substrate temperature to about 〇5〇~300C. The ugly pressure is 〇1~, and the deposition rate is about ~0.3nm/s. The thickness of the thin plate is about 1〇, and the energy level is about.
4政晶夺7層 13 a I τ例如以高頻高密度電漿鍍膜方式 (VHF_PECVD) ’其產生電漿頻率為26〜133MHz，並通 ^烧與氫氣’以及作為掺雜氣體的PH3或B2H6，以沈積 外* 或 Ρ 之祕晶石夕（Microcrystalline Silicon，hc-Si : Η) 4膜。製程上例如，設定基板溫度約為 150〜300。(：， 月工體I力為〇·1〜itQrr ’沈積速率約為Q inm/s，薄膜厚度 約為1〜3μΐη’能階約為1上V。另外，微晶石夕層13亦可 不掺雜而形成為本質之微晶梦層（Μ·⑻小本實施 例之微晶石夕層13係以本質微W層為例。 卜/專膜太陽能電池元件1可更包含一透光基板 1 dim得Μ非㈣層Π切絲基板14盘 破曰曰石夕層13之間。此外，薄膜太陽能電池元们可/包 201230357 含一透明電極層15，其設置於透光基板14與P型非晶矽 層11之間。本實施例之透光基板14可使用高穿透率之玻 璃基板，其上以濺鍍（Sputter)或化學沈積方式鍍上透明 導電氧化薄膜材料（Transparent Conducting Oxide)以作 為透明電極層15。透明電極層15可例如以參雜氟的二氧 化錫（Sn02 : F)或氧化鋅（ZnO)為主。透明電極層15 例如，約為80〜100nm，穿透率為85%以上，電阻率約為 0.01〜0.03Q-cm。在本實施例中，光線係由透光基板14與 透明電極層15進入元件内。 另外，薄膜太陽能電池元件1可更包含一金屬電極層 16，其設置位置使得N型非晶矽層12位於金屬電極層16 與微晶矽層13之間。此外，薄膜太陽能電池元件1可更 包含一透明電極層17，其設置於金屬電極層16與N型非 晶矽層12之間。透明電極層17與金屬電極層16可例如 藉由濺鍍方法沈積而成。透明電極層17可與透明電極層 15相同或類似，於此不再說明。金屬電極層16之材質可 例如為鋁、銀或其他金屬。透明電極層17厚度可約為 80nm，而金屬電極層16厚度約為150〜200nm。 圖2為本發明第二實施例之一種薄膜太陽能電池元件 1的示意圖。如圖2所示，薄膜太陽能電池元件1更包含 一本質非晶矽層（i-layer a-Si : H) 18，其設置於P型非晶 矽層11與微晶矽層13之間。薄膜太陽能電池元件1更可 包含另一本質非晶矽層（i-layer a-Si : H) 19，設置於N 型非晶矽層12與微晶矽層13之間。或者，薄膜太陽能電 201230357 池兀件1可同時包含本質非晶矽層18、19，本質非晶矽層 18 19可作用電子電洞復合（rec〇nibinati〇n)的阻擔層， 進而提升光電轉換效率。 另外’本實施例之微晶矽層13可例如為本質微晶矽 層、或P型微晶石夕層、或N型微晶石夕層。4 Zhengjing wins 7 layers of 13 a I τ, for example, by high-frequency high-density plasma coating (VHF_PECVD), which produces a plasma frequency of 26 to 133 MHz, and is burned with hydrogen and as a doping gas, PH3 or B2H6. To deposit a film of Microcrystalline Silicon (hc-Si: Η) 4 of the outer * or Ρ. For example, the substrate temperature is set to be about 150 to 300. (:, the monthly work I force is 〇·1~itQrr 'The deposition rate is about Q inm/s, and the film thickness is about 1~3μΐη' energy level is about 1 V. In addition, the microcrystalline layer 13 may not Doped and formed into the essence of the microcrystalline dream layer (Μ·(8) The microcrystalline layer 13 of the present embodiment is taken as an example of the intrinsic microW layer. The Bu/special film solar cell element 1 may further comprise a transparent substrate. 1 dim Μ Μ ( ( 四 四 四 四 四 四 基板 基板 基板 基板 基板 基板 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 。 The transparent substrate 14 of the present embodiment can use a high transmittance glass substrate on which a transparent conductive oxide film material is plated by sputtering or chemical deposition (Transparent Conducting Oxide). As the transparent electrode layer 15. The transparent electrode layer 15 may be mainly made of fluorine-doped tin dioxide (Sn02: F) or zinc oxide (ZnO). The transparent electrode layer 15 is, for example, about 80 to 100 nm, penetrating. The rate is 85% or more, and the resistivity is about 0.01 to 0.03 Q-cm. In the present embodiment, the light is made of the light-transmitting substrate 14 The thin film solar cell element 1 further includes a metal electrode layer 16 disposed such that the N-type amorphous germanium layer 12 is located between the metal electrode layer 16 and the microcrystalline germanium layer 13. The thin film solar cell element 1 may further include a transparent electrode layer 17 disposed between the metal electrode layer 16 and the N-type amorphous germanium layer 12. The transparent electrode layer 17 and the metal electrode layer 16 may be deposited, for example, by a sputtering method. The transparent electrode layer 17 may be the same as or similar to the transparent electrode layer 15, and will not be described here. The material of the metal electrode layer 16 may be, for example, aluminum, silver or other metals. The transparent electrode layer 17 may have a thickness of about 80 nm. The metal electrode layer 16 has a thickness of about 150 to 200 nm. Fig. 2 is a schematic view showing a thin film solar cell element 1 according to a second embodiment of the present invention. As shown in Fig. 2, the thin film solar cell element 1 further comprises an intrinsic amorphous germanium layer ( I-layer a-Si : H) 18, which is disposed between the P-type amorphous germanium layer 11 and the microcrystalline germanium layer 13. The thin film solar cell element 1 may further comprise another intrinsic amorphous germanium layer (i-layer a -Si : H) 19, set in N-type amorphous Between the layer 12 and the microcrystalline layer 13. Alternatively, the thin film solar power 201230357 pool element 1 can simultaneously contain the essential amorphous layer 18, 19, and the intrinsic amorphous layer 18 19 can function as an electron hole composite (rec〇nibinati The resistive layer of 〇n) further enhances the photoelectric conversion efficiency. Further, the microcrystalline germanium layer 13 of the present embodiment may be, for example, an intrinsic microcrystalline germanium layer, or a P-type microcrystalline litmus layer, or an N-type microcrystalline litmus. Floor.
另外，P型非晶矽層11、或N型非晶矽層12、或本 質非晶矽層18、19可摻雜元素表中瓜a至族之其中至 '兀素。例如，非晶矽層可以做成非晶鍺化矽（a-SiGe:H) 層’其中可以§周整錯的含量以改變非晶鍺化砂（以脱丑） 每的此，使其與埋入之微晶矽層能有更好之能階匹配以 進一步增加光電轉換效率。 山、’’不上所述，本發明在非晶矽薄膜太陽能電池中設置一 微晶石夕層。相較於神晶層，微”層可吸收較長波長之 光、泉而彌補非矽晶之不足，進而提升電池轉換效率；例 ^ ’微㈣能階約為UeV，其吸收級長範圍為5〇〇〜 」〇聰’將可有效彌補非㈣無法吸收之光波長進而增加 二之轉換效率。此外’相較於非晶石夕層，微晶梦層具有 照衰退抵抗能力’而提升7^件效能。並且本發明 二薄膜太陽能電池中設置—微晶石夕層，可減少 由二^ 度’進而有效降低光照衰退現象。此外， 之人各層都可以在破璃基板上全部一次沈積完 吊U現有矽薄膜太陽電池產業引用直。 以上所述僅為舉例性，而 本發明之精神與㈣，而行2何未脫離 、運仃之寺效修改或變更，均 201230357 應包含於後附之申請專利範圍中。 【圖式簡單說明】 圖1為本發明第一實施例之一 的示意圖；以及 種薄膜太陽能電 池元件 圖2為本發明第 的示意圖。 二實施例之一種薄膜太陽能電池元件Further, the P-type amorphous germanium layer 11, or the N-type amorphous germanium layer 12, or the intrinsic amorphous germanium layer 18, 19 may be doped to the elemental melon in the elemental table. For example, the amorphous germanium layer can be made of an amorphous germanium telluride (a-SiGe:H) layer, which can be used to change the amount of amorphous germanium sand (to remove ugly). The buried microcrystalline germanium layer can have better energy level matching to further increase the photoelectric conversion efficiency. The present invention provides a microcrystalline layer in an amorphous germanium thin film solar cell. Compared with the crystal layer, the micro-layer can absorb longer wavelength light and spring to make up for the lack of non-crystal, and thus improve the battery conversion efficiency; for example, 'micro (four) energy level is about UeV, and its absorption level is 5 〇〇~ "〇聪" will effectively compensate for the wavelength of light that cannot be absorbed by (4) and thus increase the conversion efficiency. In addition, the microcrystalline dream layer has the ability to resist recession and improve the efficiency of the film compared to the amorphous layer. Further, in the second thin film solar cell of the present invention, the microcrystalline layer can be reduced to reduce the light decay phenomenon by the second degree. In addition, all layers of the human body can be deposited on the glass substrate all at once. The above description is only exemplary, and the spirit of the present invention and (4), and the reason why the line 2 has not been detached, and the modification or modification of the effect of the invention, 201230357 shall be included in the scope of the appended patent application. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic view showing a first embodiment of the present invention; and a thin film solar cell element. Fig. 2 is a schematic view showing the first embodiment of the present invention. A thin film solar cell component of two embodiments
【.主Μ要元件符號說明】 •薄膜太陽能電池元件 11 · Ρ型非晶石夕層 12: Ν型非晶矽層 13 .微晶石夕層 14:透光基板 、17:透明電極層 16:金屬電極層 18、1 Q ·丄[Description of main component symbols] • Thin film solar cell element 11 • Amorphous amorphous layer 12: Ν-type amorphous germanium layer 13. Microcrystalline layer 14: transparent substrate, 17: transparent electrode layer 16 : Metal electrode layer 18, 1 Q ·丄
•本質非晶矽層 10• Essential amorphous layer 10