200933906 九、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及其製造方法，尤其 關於一種具異質介面之太陽能電池及其製造方法。 【先前技術】 ' 太陽能電池是一種能量轉換的光電元件，它是經由 - 太陽光照射後，把光的能量轉換成電能，此種光電元件 〇 稱為太陽能電池（Solar Cell)。從物理學的角度來看，有 人稱之為光伏（Photovoltaic，簡稱PV)電池。 傳統的太陽能電池的主要材料，可以是石夕、珅化鎵 (GaAs)、磷化銦（InP)、蹄化録（CdTe)及疏化福（cdS)等。 利用這幾類材料所製造出的太陽能電池所吸收的光線的 波長範圍不同，也分別有其不同的應用領域。舉例而言， 基於矽材料之太陽能電池能轉換的光波長範圍是1 〇〇〇_ 13 00nm、基於珅化鎵（GaAs)材料之太陽能電池能轉換的 ❹光波長範圍是7〇〇-900nm、基於碲化錫（cdTe)材料之太 陽能電池能轉換的光波長範圍是500-9OOnm、而基於硫 - 化編（CdS)材料之太陽能電池能轉換的光波長範圍是4〇〇_ 600nm 〇 由於太陽光的波長分佈範圍报廣，單單利用石夕、石申 化鎵（GaAs)、麟化銦（InP)、碲化鑛（CdTe)或硫化録（cdS) 材料所製作出的太陽能電池僅有一部分的太陽光轉換成 電能。因此，習知技術一直無法克服此缺點。此外，習 知之太陽能電池之受光面通常形成有手指狀電極，因而 6 200933906 遮蔽部分受光面積，造成效率無法有效被提升。 【發明内容】 因此，本發明之一個目的係摇 _ a ^ j诉杈供一種具異質介面之 太陽能電池及其製造方法，其可 八j U吸收較大範圍的波長 的光線，並降低光線的遮蔽率。 提供一種具異質介面之太陽 一保護層、一背面電極層、 層°石夕基板具有一正面及一 Ο 為逹上述目的，本發明 能電池，其包含一矽基板、 一異質材料層及一透明導電 背面。保護層之一正面連結至矽基板之背面。背面電極 層電連接至石夕基板，並貫穿保護層而伸出保護層之一背 面。異質材料層形成㈣基板之正面上。異質材料層鱼 矽基板分別吸收不同波長範圍之光線而產生—電壓差。 透明導電層形成於異質材料層上。 本發明亦提供一種具異質介面之太陽能電池之製造 方法，包含以下步驟··提供一矽基板，矽基板具有一正 e面及一背面；於矽基板之背面上形成一保護層，保護層 之—正面面對矽基板之背面；於保護層之一背面形成— 背面電極層；燒結背面電極層，使背面電極層穿透保護 層而電連接至矽基板，·於矽基板之正面上形成一里質材 料層，異質材料層與矽基板分別吸收不同波長範圍之光 線而產生一電壓差；及於異質材料層上形成—透明導200933906 IX. Description of the Invention: [Technical Field] The present invention relates to a solar cell and a method of manufacturing the same, and more particularly to a solar cell having a heterogeneous interface and a method of fabricating the same. [Prior Art] 'A solar cell is an energy-converting photovoltaic element that converts light energy into electrical energy after being irradiated by sunlight. This photoelectric element is called a solar cell. From a physics point of view, some people call it Photovoltaic (PV) batteries. The main materials of conventional solar cells may be Shi Xi, gallium antimonide (GaAs), indium phosphide (InP), hoof (CdTe), and blush (cdS). The solar cells produced by these types of materials absorb different wavelengths of light, and each has its own different application fields. For example, a solar cell based on a germanium material can convert a light wavelength range of 1 〇〇〇 _ 1300 nm, and a solar cell based on a gallium arsenide (GaAs) material can convert a neon wavelength range of 7 〇〇 to 900 nm. Solar cells based on antimony telluride (cdTe) materials can convert light wavelengths in the range of 500-9OOnm, while solar cells based on sulfur-based (CdS) materials can convert light wavelengths in the range of 4〇〇 to 600nm. The wavelength range of light is widely reported, and only a part of the solar cells produced by using Shixi, Shishenhua gallium (GaAs), lining indium (InP), strontium ore (CdTe) or sulphide (cdS) materials are only partially used. The sunlight is converted into electrical energy. Therefore, conventional techniques have been unable to overcome this disadvantage. In addition, the light-receiving surface of a conventional solar cell is usually formed with a finger-shaped electrode, so that the light-receiving area of the shadow portion is partially blocked, and the efficiency cannot be effectively improved. SUMMARY OF THE INVENTION Accordingly, it is an object of the present invention to provide a solar cell having a heterogeneous interface and a method of fabricating the same, which can absorb light of a wide range of wavelengths and reduce light. Coverage rate. Providing a solar-protective layer having a heterogeneous interface, a back electrode layer, and a layer having a front surface and a top surface, the battery of the present invention comprising a germanium substrate, a heterogeneous material layer and a transparent Conductive back. One of the protective layers is bonded to the back side of the substrate. The back electrode layer is electrically connected to the stone substrate and extends through the protective layer to extend over the back side of one of the protective layers. A layer of heterogeneous material is formed on the front side of the (4) substrate. The heterogeneous material layer of the fish 矽 substrate absorbs light of different wavelength ranges to generate a voltage difference. A transparent conductive layer is formed on the layer of heterogeneous material. The invention also provides a method for manufacturing a solar cell with a heterogeneous interface, comprising the steps of: providing a substrate having a positive e-plane and a back surface; forming a protective layer on the back surface of the germanium substrate, the protective layer - facing the back side of the substrate; forming a back electrode layer on the back side of one of the protective layers; sintering the back electrode layer such that the back electrode layer penetrates the protective layer to electrically connect to the germanium substrate, and forms a front surface of the germanium substrate The lining material layer, the heterogeneous material layer and the ruthenium substrate respectively absorb light of different wavelength ranges to generate a voltage difference; and form a transparent guide on the heterogeneous material layer
Si 形成 矽基 藉由上述實施樣態’可以在薄型化的矽基板上 異質材料層，以建構出具異質介面之太陽能電池。 7 200933906 板吸收長波長的光線，異質材料層吸收短波長的光線， 透明導電層同時具有抗反射及收集載子的功效。因此， 不需要具有習知技術之手指狀電極，使得光線遮蔽率可 以有效被降低，進而提升太陽能電池的效率。由於矽基 板不需要太厚，可以有效降低成本，並減少對矽晶圓之 依賴。 - 為讓本發明之上述内容能更明顯易懂，下文特舉一 * 較佳實施例，並配合所附圖式，作詳細說明如下。 【實施方式】 立圖1顯示依據本發明第一實施例之太陽能電池之示 意圖。如圖1所示，本實施例之太陽能電池包含一矽基 板10保護層20、一背面電極層30、一異質材料層4〇 及一透明導電層50。 矽基板ίο具有一正面10F及一背面1〇B。保護層Si forms a ruthenium substrate. The heterogeneous material layer can be formed on a thinned tantalum substrate by the above-described embodiment to construct a solar cell having a heterogeneous interface. 7 200933906 The board absorbs long-wavelength light. The heterogeneous material layer absorbs short-wavelength light. The transparent conductive layer has anti-reflection and collects carriers. Therefore, a finger electrode having a conventional technique is not required, so that the light shielding rate can be effectively reduced, thereby improving the efficiency of the solar cell. Since the ruthenium substrate does not need to be too thick, it can effectively reduce the cost and reduce the dependence on the ruthenium wafer. In order to make the above description of the present invention more comprehensible, a preferred embodiment will be described below in detail with reference to the accompanying drawings. [Embodiment] Fig. 1 shows the schematic of a solar cell according to a first embodiment of the present invention. As shown in FIG. 1, the solar cell of the present embodiment comprises a protective layer 20 of a substrate 10, a back electrode layer 30, a heterogeneous material layer 4A, and a transparent conductive layer 50. The substrate ίο has a front surface 10F and a back surface 1 〇 B. The protective layer
係由氮化矽或二氧化矽所構成。保護層2〇之一正面2〇F 〇連結至矽基板1〇之背面1〇B。背面電極層3〇電連接至 矽基板10,並貫穿保護層2〇而伸出保護層2〇之一背面 2〇B ^異質材料層4〇形成於矽基板1〇之正面i〇f上，異 質材料層40與矽基板1〇分別吸收不同波長範圍之光線 ，產生一電壓差。透明導電層5〇係由氧化銦鍚（ιτ〇)或 氧化辞（ΖηΟ)所構成，且透明導電層5〇形成於異質材料 層40上。 於本實施例中，矽基板10係為一 ρ型矽層，且異質 材料層40係為一 Ν型半導體層，其材料譬如是砷化鎵 200933906 (GaAs)、磷化銦（InP)、碲化鎘（cdTe)及硫化鎘（CdS)。或 者，矽基板10係為一 N型矽層，且異質材料層4〇係為 一 P型半導體層，其材料譬如是砷化鎵（GaAs)、磷化銦 (InP)、碲化鎘（CdTe)及硫化鎘（CdS)。異質材料層4〇可 以藉由沈積、濺鍍及蒸鍍法形成，藉由控制材料的成分 及濃度’即可控制所沈積材料為p型或N型。 - 圖2顯示依據本發明第二實施例之太陽能電池之示 . 意圖。如圖2所示，本實施例係類似於第一實施例，不 〇 同之處在於矽基板10係由一 P/N型矽層12及一 N/P型 石夕層14所組成，且異質材料層4〇係由一 p/N型半導體 層42及一 N/P型半導體層44所組成。 P/N i半導體層42之材料譬如是坤化錄（GaAs)、鱗 化銦（InP)、碲化鎘（cdTe)及硫化鎘（CdS)。N/P型半導體 層44之材料譬如是砷化鎵（GaAs)、磷化銦（Inp)、碲化鎘 (CdTe)及硫化鑛（CdS)。 圖3顯不依據本發明之太陽能電池之製造方法之流 ❹程圖。如圖3所示，本發明之太陽能電池之製造方法包 ， 含以下步驟。 • 首先，於步驟S1，提供一矽基板10。矽基板1〇具 有一正面10F及一背面1〇B。 接著’於步驟S2，於矽基板10之背面ιοΒ上形成 一保濩層20。保護層20之一正面20F面對矽基板1〇之 背面10B。 然後，於步驟S3，於保護層2〇之一背面2〇B形成 一背面電極層30。背面電極層30之材料通常為銀膠。 200933906 接著，於步驟S4’燒結背面電極層3〇，使背面電極 層30穿透保護層20而電連接至矽基板1 〇。 然後’於步驟S5’於石夕基板1〇之正面上形成 一異質材料層40。異質材料層40與矽基板1 〇分別吸收 不同波長範圍之光線而產生一電壓差。 最後’於步驟S6，於異質材料層4〇上形成一透明 導電層50。各層的特性已經說明於上述内容中，於此不 再詳述。 〇 藉由本發明之上述構造，可以在薄型化的矽基板上 形成異質材料層，以建構出具異質介面之太陽能電池。 矽基板吸收長波長的光線，異質材料層吸收短波長的光 線，透明導電層同時具有抗反射及收集載子的功效。因 此’不需要具有習知技術之手指狀電極，使得光線遮蔽 率可以有效被降低，進而提升太陽能電池的效率。由於 矽基板不需要太厚，可以有效降低成本，並減少對矽晶 ❹ 在較佳實施例之詳細說明中所提出之㈣實施㈣ -用以方便說明本發明之技術内容，而非將本發明 ‘：制於上述實施例，在不超出本發明之精神及以下” 之範：圍之情況’所做之種種變化實施’皆屬於本發： 10 200933906 【圖式簡單說明】 圖1顯不依據本發明第一實施例之太陽能電池之示 意圖。 圖2顯示依據本發明第二實施例之太陽能電池之示 意圖。 圖3顯示依據本發明之太陽能電池之製造方法 ' 程圖。 • 【主要元件符號說明】 ® Sl-S6 :方法步驟 10 :碎基板 10B :背面 10F :正面 12 : P/N型矽層 14 : N/P型矽層 2〇 :保護層 20B :背面 ❹ 2〇F :正面 3 0 .背面電極層 4〇 :異質材料層 42 : P/N型半導體層 44 ·· N/P型半導體層 5〇 :透明導電層 11It is composed of tantalum nitride or hafnium oxide. One of the front faces of the protective layer 2 is connected to the back surface 1B of the substrate 1 . The back electrode layer 3 is electrically connected to the ruthenium substrate 10 and extends through the protective layer 2 〇 and protrudes from the back surface of the protective layer 2 〇 2 〇 B ^ the heterogeneous material layer 4 〇 is formed on the front surface 〇 of the 矽 substrate 1 , The heterogeneous material layer 40 and the ruthenium substrate 1 吸收 absorb light of different wavelength ranges, respectively, to generate a voltage difference. The transparent conductive layer 5 is made of indium oxide bismuth (ΖτΟ) or oxidized (ΖηΟ), and a transparent conductive layer 5 is formed on the heterogeneous material layer 40. In the present embodiment, the germanium substrate 10 is a p-type germanium layer, and the heterogeneous material layer 40 is a germanium-type semiconductor layer, such as gallium arsenide 200933906 (GaAs), indium phosphide (InP), germanium. Cadmium (cdTe) and cadmium sulfide (CdS). Alternatively, the germanium substrate 10 is an N-type germanium layer, and the heterogeneous material layer 4 is a P-type semiconductor layer, such as gallium arsenide (GaAs), indium phosphide (InP), and cadmium telluride (CdTe). ) and cadmium sulfide (CdS). The heterogeneous material layer 4 can be formed by deposition, sputtering, and evaporation, and the deposited material can be controlled to be p-type or N-type by controlling the composition and concentration of the material. - Figure 2 shows an illustration of a solar cell in accordance with a second embodiment of the present invention. As shown in FIG. 2, the present embodiment is similar to the first embodiment, and the difference is that the germanium substrate 10 is composed of a P/N type germanium layer 12 and an N/P type stone layer 14, and The heterogeneous material layer 4 is composed of a p/N type semiconductor layer 42 and an N/P type semiconductor layer 44. The material of the P/N i semiconductor layer 42 is, for example, Kunhua (GaAs), indium arsenide (InP), cadmium telluride (cdTe), and cadmium sulfide (CdS). The material of the N/P type semiconductor layer 44 is, for example, gallium arsenide (GaAs), indium phosphide (Inp), cadmium telluride (CdTe), and sulfide ore (CdS). Fig. 3 is a flow chart showing a method of manufacturing a solar cell according to the present invention. As shown in Fig. 3, the method for manufacturing a solar cell of the present invention comprises the following steps. • First, in step S1, a substrate 10 is provided. The substrate 1 has a front surface 10F and a back surface 1B. Next, in step S2, a protective layer 20 is formed on the back surface of the substrate 10. The front surface 20F of one of the protective layers 20 faces the back surface 10B of the crucible substrate 1A. Then, in step S3, a back electrode layer 30 is formed on the back surface 2B of one of the protective layers 2''. The material of the back electrode layer 30 is usually silver paste. 200933906 Next, the back electrode layer 3 is sintered in step S4', and the back electrode layer 30 is penetrated through the protective layer 20 to be electrically connected to the germanium substrate 1 . Then, a layer of the heterogeneous material 40 is formed on the front surface of the Shixi substrate 1' in step S5'. The heterogeneous material layer 40 and the germanium substrate 1 吸收 respectively absorb light of different wavelength ranges to generate a voltage difference. Finally, in step S6, a transparent conductive layer 50 is formed on the heterogeneous material layer 4?. The characteristics of each layer have been described in the above, and will not be described in detail herein. With the above configuration of the present invention, a heterogeneous material layer can be formed on a thinned germanium substrate to construct a solar cell having a heterogeneous interface. The ruthenium substrate absorbs long-wavelength light, and the heterogeneous material layer absorbs short-wavelength light. The transparent conductive layer has both anti-reflection and carrier-collecting effects. Therefore, a finger electrode having a conventional technique is not required, so that the light shielding rate can be effectively reduced, thereby improving the efficiency of the solar cell. Since the ruthenium substrate does not need to be too thick, the cost can be effectively reduced, and the (4) implementation (4) proposed in the detailed description of the preferred embodiment is reduced to facilitate the description of the technical contents of the present invention, instead of the present invention. ': The above embodiment is carried out without departing from the spirit of the present invention and the following: "The various changes made by the situation" are all in this issue: 10 200933906 [Simple description of the diagram] Figure 1 shows no basis 2 is a schematic view of a solar cell according to a second embodiment of the present invention. Fig. 2 is a view showing a solar cell according to a second embodiment of the present invention. Fig. 3 is a view showing a method of manufacturing a solar cell according to the present invention. 】 ® Sl-S6 : Method Step 10 : Broken Substrate 10B : Back 10F : Front 12 : P/N Type 矽 Layer 14 : N/P Type 矽 Layer 2 〇 : Protective Layer 20B : Back ❹ 2 〇 F : Front 3 0 Back surface electrode layer 4: Heterogeneous material layer 42: P/N type semiconductor layer 44 · N/P type semiconductor layer 5: Transparent conductive layer 11