201221660 六、發明說明 【發明所屬之技術領域】 本發明係關於使用於CIGS(Cu-In-Ga-Se四元合金）太 陽電池之光吸收層形成之含有鹼金屬的Cu-Ga合金濺鍍靶 之製造方法及Cu-Ga合金濺鍍靶。 【先前技術】 近年來，將以Cu-In-Ga-Se四元合金爲代表之薄膜化 合物半導體使用於光吸收層之薄膜太陽電池已被實用化。 此Cu-In-Ga-Se薄膜太陽電池係具有如以下之基本構 造：於玻璃基板上形成作爲正電極的Mo電極層、於此 Mo電極層上形成由 Cu-In-Ga-Se合金膜而成之光吸收 層、於此光吸收層上形成由ZnS、CdS等而成之緩衝層、 且於此緩衝層上形成作爲負電極之透明導電膜（例如，參 照專利文獻1)。 爲了使此Cu-In-Ga-Se薄膜太陽電池高性能化，有必 要於光吸收層添加鈉等之鹼金屬。 一般而言，將以鹼石灰爲主成分之鹼石灰玻璃等用於 基板時，基板中所含之鹼金屬會對光吸收層擴散，因此無 須特意添加鹼金屬。 另一方面，欲將耐熱性優良的無鹼玻璃或低鹼玻璃用 於基板時，或欲以製造可撓性太陽電池爲目的而使用金屬 基板或塑膠基板時，無法期待鹼金屬由基板擴散，故有必 要藉由使用鹼前驅物，使鹼金屬對光吸收層擴散（例如， -5 - 201221660 參照專利文獻2)。 專利文獻2中記載的方法’係形成鹼前驅物，且使鹼 金屬由該處對光吸收層擴散。此方法因爲設有鹼前驅物， 步驟數會増加’在產業上而言有缺陷。再者，使鹼金屬如 此地對光吸收層擴散的方法中，難以將鹼金屬的添加量控 制到微量。進一步，此方法在考慮到光吸收層的厚度方向 時，具有離鹼金屬源越近則鹼金屬的濃度越濃，相反地與 鹼金屬源相反側則鹼金屬的濃度變稀之傾向。這在謀求太 陽電池之高性能化而言，不能說是良好的手段。 因而，若於製造Cu-In-Ga-Se光吸收層時所使用的成 膜材料、亦即於濺鍍靶或蒸鍍材料中添加鹼金屬，則能夠 於Cu-In-Ga-Se光吸收層中添加入鹼金屬。但是，鹼金屬 爲反應性非常高的金屬，操作上有困難。因此，於薄膜太 陽電池之製造形成含有鹼金屬的光吸收層的濺鍍靶之方法 中，正尋求不使用鹼金屬單質而製造含有鹼金屬之濺鍍靶 的方法。 [先前技術文獻] [專利文獻] [專利文獻1 ]日本特開2 0 0 8 - 1 3 8 2 3 2號公報 [專利文獻2]國際公開第2009/1 1 6626號 【發明內容】 [發明所欲解決之課題] 因而，本發明係有鑑於如此長久以來的實情而提出 -6 - 201221660 者，其目的在提供不使用操作困難之鹼金屬單質，而製造 含有鹼金屬之Cu-Ga合金濺鍍靶的Cu-Ga合金濺鍍靶之 製造方法及藉由此製造方法而得的Cu-Ga合金濺鍍靶。 [用以解決課題之手段] 達成上述目的之本發明的Cu-Ga合金濺鍍靶之製造方 法，其特徵爲於Cu-Ga合金濺鍍靶中，以含有上述鹼金屬 〇.〇1〜5質量％的方式’至少燒結混合含有鹼金屬之有機 物、與含有鎵及銅的Cu-Ga合金粉末之混合粉末，藉以製 造含有鹼金屬〇.〇1〜5質量％之Cu-Ga合金濺鍍靶。 又，達成上述目的之本發明的Cu-Ga合金濺鍍祀，其 特徵爲，係至少燒結混合含有鹼金屬之有機物、與含有鎵 及銅的Cu-Ga合金粉末之混合粉末而得且至少含有銅、鎵 及0.01〜5質量％之鹼金屬。 [發明之效果] 本發明中’藉由至少燒結混合含有鹼金屬之有機物、 與含有鎵及銅的Cu_Ga合金粉末之混合粉末而製造Cu-Ga 合金濺鍍靶’因爲不使用反應性高的鹼金屬，故能夠使混 合粉末不發熱而安全地製造含有鹼金屬0.01〜5質量％之 Cu-Ga合金濺鑛靶。 【實施方式】 以下詳細說明應用了本發明之Cu-Ga合金濺鍍祀之製 201221660 造方法及藉由此製造方法而得之Cu-Ga合金濺銨靶。另 外，若無特殊限定，本發明並不受以下詳細說明所限定。201221660 VI. Description of the Invention [Technical Field of the Invention] The present invention relates to an alkali metal-containing Cu-Ga alloy sputtering target formed using a light absorbing layer of a CIGS (Cu-In-Ga-Se quaternary alloy) solar cell. Manufacturing method and Cu-Ga alloy sputtering target. [Prior Art] In recent years, thin film solar cells using a thin film compound semiconductor typified by a Cu-In-Ga-Se quaternary alloy have been put into practical use. The Cu-In-Ga-Se thin film solar cell system has a basic structure in which a Mo electrode layer as a positive electrode is formed on a glass substrate, and a Cu-In-Ga-Se alloy film is formed on the Mo electrode layer. A light-absorbing layer formed thereon, a buffer layer made of ZnS or CdS or the like is formed on the light-absorbing layer, and a transparent conductive film as a negative electrode is formed on the buffer layer (see, for example, Patent Document 1). In order to improve the performance of the Cu-In-Ga-Se thin film solar cell, it is necessary to add an alkali metal such as sodium to the light absorbing layer. In general, when soda lime glass containing soda lime as a main component is used for the substrate, the alkali metal contained in the substrate diffuses into the light absorbing layer, so that it is not necessary to add an alkali metal. On the other hand, when an alkali-free glass or a low-alkali glass which is excellent in heat resistance is used for a substrate, or when a metal substrate or a plastic substrate is used for the purpose of manufacturing a flexible solar cell, alkali metal cannot be expected to diffuse from the substrate. Therefore, it is necessary to diffuse the alkali metal to the light absorbing layer by using an alkali precursor (for example, -5 - 201221660, refer to Patent Document 2). The method described in Patent Document 2 forms an alkali precursor, and the alkali metal is diffused from the light absorbing layer there. Since this method is provided with an alkali precursor, the number of steps will increase, which is industrially defective. Further, in the method of diffusing an alkali metal to the light absorbing layer, it is difficult to control the amount of the alkali metal added to a trace amount. Further, in the case where the thickness direction of the light absorbing layer is taken into consideration, the concentration of the alkali metal becomes richer as it is closer to the alkali metal source, and conversely, the concentration of the alkali metal becomes thinner on the side opposite to the alkali metal source. This is not a good means for pursuing the high performance of solar cells. Therefore, when a film-forming material used for producing a Cu-In-Ga-Se light absorbing layer, that is, an alkali metal is added to a sputtering target or a vapor deposition material, Cu-In-Ga-Se light absorption can be performed. An alkali metal is added to the layer. However, the alkali metal is a highly reactive metal and is difficult to handle. Therefore, in the method of producing a sputtering target containing an alkali metal-containing light absorbing layer in the production of a thin film solar cell, a method of producing an alkali metal-containing sputtering target without using an alkali metal element is being sought. [PRIOR ART DOCUMENT] [Patent Document 1] [Patent Document 1] Japanese Patent Laid-Open Publication No. H0 8 - 1 3 8 2 3 2 [Patent Document 2] International Publication No. 2009/1 1 6626 [Summary of Invention] [Invention OBJECTS TO BE SOLVED BY THE INVENTION Therefore, the present invention has been proposed in view of such a long-standing fact, -6 - 201221660, which aims to produce a Cu-Ga alloy containing an alkali metal without using an alkali metal element which is difficult to handle. A method for producing a target Cu-Ga alloy sputtering target and a Cu-Ga alloy sputtering target obtained by the method of the present invention. [Means for Solving the Problem] The method for producing a Cu-Ga alloy sputtering target of the present invention which achieves the above object is characterized in that the Cu-Ga alloy sputtering target contains the above-mentioned alkali metal 〇.〇1 to 5 The % by mass method 'sintering at least a mixed powder containing an alkali metal-containing organic substance and a Cu-Ga alloy powder containing gallium and copper to produce a Cu-Ga alloy sputtering target containing an alkali metal lanthanum 〇1 to 5 mass% . Further, the Cu-Ga alloy sputtering target of the present invention which achieves the above object is characterized in that at least a mixed powder containing an alkali metal-containing organic substance and a Cu-Ga alloy powder containing gallium and copper is sintered and at least contained Copper, gallium and 0.01 to 5% by mass of an alkali metal. [Effects of the Invention] In the present invention, a Cu-Ga alloy sputtering target is produced by at least sintering and mixing a mixed metal containing an alkali metal and a Cu_Ga alloy powder containing gallium and copper, because a highly reactive alkali is not used. Since the metal is used, it is possible to safely produce a Cu-Ga alloy splash target containing 0.01 to 5% by mass of an alkali metal without causing the mixed powder to generate heat. [Embodiment] Hereinafter, a Cu-Ga alloy sputtering ruthenium-made method 201221660 to which the present invention is applied and a Cu-Ga alloy splatter target obtained by the production method will be described in detail. Further, the present invention is not limited by the following detailed description unless otherwise specified.
Cu-Ga合金濺鍍靶係爲含有銅與鎵之合金及鹼金屬 者。此Cu-Ga合金濺鍍靶係以如以下之方式，能夠不使用 鹼金屬而加以製造。The Cu-Ga alloy sputtering target system is an alloy containing copper and gallium and an alkali metal. This Cu-Ga alloy sputtering target can be produced without using an alkali metal as follows.
Cu-Ga合金濺鍍靶之製造方法，係藉由混合含有鎵及 銅之Cu-Ga合金粉末與含有鹼金屬之有機物，且燒結所得 到之混合粉末，以製造Cu-Ga合金濺鍍靶。The Cu-Ga alloy sputtering target is produced by mixing a Cu-Ga alloy powder containing gallium and copper with an organic substance containing an alkali metal, and sintering the obtained mixed powder to produce a Cu-Ga alloy sputtering target.
Cu_Ga合金粉末係含有鎵（Ga)l〜4 5質量％，剩餘部分 由銅（Cu)及不可避免的雜質構成，且粒徑爲10~5 00μΐΏ左 右的粉末。鎵的比例超過45質量％時，於之後進行之燒 結混合粉末的步驟中，熔點低的鎵會熔解，於一部分產生 液相，故變得無法得到均勻組織的濺鍍靶。The Cu_Ga alloy powder contains gallium (Ga) 1 to 45 mass%, and the remainder is composed of copper (Cu) and unavoidable impurities, and has a particle diameter of about 10 to 500 μm. When the proportion of gallium exceeds 45% by mass, in the step of sintering the mixed powder which is carried out later, gallium having a low melting point is melted, and a part of the liquid phase is generated, so that a sputtering target having a uniform structure cannot be obtained.
Cu-Ga合金粉末之粒徑低於ΙΟμιη時，係於燒結混合 粉末的步驟中將混合粉末塡充於石墨模，但粉末容易由石 墨模的空隙漏出，故不適當。Cu-Ga合金粉末之粒徑超過 5 ΟΟμιη時，會成爲即使燒結混合粉末亦無法得到高密度之 燒結體的狀態。就Cu-Ga合金粉末之製造方法而言，霧化 法、及粉碎合金化後之錠塊之方法均可。 含有鹼金屬之有機物係爲含有於太陽電池之光吸收層 中含有的鹼金屬者。含有鹼金屬之有機物具體而言可列舉 以脂肪酸鹽之粉末或C、H、0'S、Na、Li、K等爲成分 之硫酸烷酯鹽、聚氧乙烯烷基醚硫酸酯鹽、苯磺酸烷酯鹽 等粉末。 -8- 5? 201221660 作爲鹼金屬者，就提高太陽電池之發電效率上，最佳 爲鈉（Na)。於Cu-Ga合金粉末中含有鈉時，係使用以C、 Η、0、S、Na爲成分之例如硫酸烷酯鈉鹽粉末。 此處，不使用金屬鈉單質的理由，係因鈉之反應性非 常高，難以操作之故。鈉在空氣中會顯現潮解性，且與水 會激烈反應而發熱。進一步地，鈉有腐蝕裝置之虞。再 者，如氟化鈉或氯化鈉之鈉鹵化物，雖無如金屬鈉般有發 熱之虞，但鹵素會作爲雜質而混入光吸收層，因此可能會 對太陽電池之特性帶來不良影響，故不適當。另一方面， 如上述之硫酸烷酯鈉粉末之含有鹼金屬之有機物，因操作 容易，且無腐蝕裝置之虞，亦不會於光吸收層混入雜質， 不會對太陽電池之特性帶來不良影響，因此爲適合。When the particle size of the Cu-Ga alloy powder is less than ΙΟμηη, the mixed powder is impregnated into the graphite mold in the step of sintering the mixed powder, but the powder is easily leaked from the void of the graphite mold, which is not appropriate. When the particle size of the Cu-Ga alloy powder exceeds 5 μm, the sintered body of high density cannot be obtained even if the mixed powder is sintered. As for the method for producing the Cu-Ga alloy powder, the atomization method and the method of pulverizing the alloyed ingot may be used. The organic substance containing an alkali metal is an alkali metal contained in a light absorbing layer of a solar cell. Specific examples of the organic substance containing an alkali metal include a powder of a fatty acid salt or an alkyl sulfate salt of a component of C, H, 0'S, Na, Li, K, or the like, a polyoxyethylene alkyl ether sulfate salt, and an alkylbenzenesulfonate. A powder such as an ester salt. -8- 5? 201221660 As an alkali metal, sodium (Na) is the best for improving the power generation efficiency of solar cells. When sodium is contained in the Cu-Ga alloy powder, for example, sodium salt of sodium sulphate as a component of C, Η, 0, S, and Na is used. Here, the reason why the metal sodium is not used is because the reactivity of sodium is extremely high and it is difficult to handle. Sodium will appear deliquescent in the air and will react violently with water to heat up. Further, sodium has a flaw in the corrosion device. Furthermore, sodium halides such as sodium fluoride or sodium chloride do not have the same heat as metal sodium, but halogens are mixed as impurities into the light absorbing layer, which may adversely affect the characteristics of solar cells. Therefore, it is not appropriate. On the other hand, the alkali metal-containing organic substance of the above sodium alkoxide sulfate powder is easy to handle, and is free from corrosion of the device, and does not mix impurities in the light absorbing layer, and does not cause deterioration of characteristics of the solar cell. The effect is therefore suitable.
Cu-Ga合金濺鍍靶之製造方法中，係使用混合上述 Cu-Ga合金粉末與含有鹼金屬之有機物而得之混合粉末， 作爲原料粉末。此混合粉末，係使Cu-Ga合金粉末與含有 鹼金屬之有機物，以所製造之Cu-Ga合金濺鍍靶中含有鹼 金屬0.01-5質量％的方式混合而製造。 例如，鹼金屬爲鈉的情況時，係以於所製造之Cu-Ga 合金濺鍍靶中，含有鈉0.01〜5質量％的方式，混合硫酸烷 酯鈉等與Cu-Ga合金粉末來製造混合粉末。所製造的濺鍍 靶中之鈉含量低於0.01質量％時，係與使用未添加鈉之濺 鍍靶來形成光吸收層的情況相同的狀態，超過5質量％ 時，會成爲在製造中時Cu-Ga合金濺鍍靶產生破裂的狀 態。因此，係以於所製造之Cu-Ga合金濺鍍靶中，鈉含量 -9 - 201221660 爲0.0 1 ~5質量％的方式來製造混合粉末。鈉以外之鹼金 屬，亦因爲同樣的理由，以於所製造之Cu-Ga合金濺鍍靶 中之含量爲〇·〇1〜5質量％的方式來製造混合粉末。此處， 製造混合粉末時應注意者，係在於Cu-Ga合金濺鍍靶如後 所述，能夠藉由燒結混合粉末而製造，因此必須考慮到硫 酸烷酯鹽粉末等之含有鹼金屬之有機物因熱分解導致之重 量減少，來製造混合粉末。 此處，於製造Cu-Ga合金濺鍍靶時，於濺鍍靶中含有 硫的情況時，硫會將結晶組織保持微細，且具有得到均 勻、且高密度之濺鍍靶的作用。因此，較佳爲於Cu-Ga合 金濺鍍靶之原料中含有硫。 硫成分較佳爲於所製造之Cu-Ga合金濺鍍靶中含有 0.01〜5質量％之範圍。低於0.01質量％時，會成爲無法將 結晶組織保持微細的狀態，超過5質量％時，相反地會成 爲靶之密度降低的狀態。因此，藉由使Cu-Ga合金濺鍍靶 中之硫成分含量在〇 . 〇 1〜5質量％的範圍內，能夠將結晶組 織保持微細、且得到高密度之靶。 於製造Cu-Ga合金濺鍍靶時，藉由調整含有鹼金屬及 硫之硫酸烷酯鹽等、與不含有硫之含有鹼金屬之有機物的 混合比例，而能夠調整所製造之Cu-Ga合金濺鍍靶中含有 之鹼金屬與硫的比率。作爲不含有硫之含有鹼金屬之有機 物者，可列舉脂肪酸鈉等之脂肪酸鹽爲例。 鹼金屬及硫的含量，可藉由原子吸光分析裝置或 ICP(Inductively Coupled Plasma)發光分光分析裝置等來 -10- 201221660 測定。 製造Cu-Ga合金濺鍍祀之方法，係將混合含有鎵及銅 之Cu-Ga合金粉末與含有鹼金屬之有機物的混合粉末加熱 後，進行燒結。 具體而言，燒結前的加熱步驟，係將混合粉末在真空 或惰性環境中’於3 00〜600°C進行加熱，以去除揮發成 分。藉由此加熱步驟，脂肪酸鹽或硫酸烷酯鹽等之含有鹼 金屬之有機物中的C、Η、Ο大部分會揮發，而不殘留在 所製造之Cu-Ga合金濺鍍靶中。若不進行此3 00〜600°C之 加熱，則揮發成分會殘留在Cu-Ga合金濺鍍靶中。 加熱混合粉末後，藉由在真空或惰性環境中於 40kg/cm2以上的加壓之下，於600〜900°C燒結混合粉末， 可得到濺鍍靶。此加熱及燒結步驟係使用加壓燒結爐，能 夠以連續予以加熱與燒結之程式來進行，亦能夠使用脫脂 爐與加壓燒結爐的2台裝置，將加熱與燒結在不同裝置進 行。 此製造Cu-Ga合金濺鍍靶的方法中，藉由在進行燒結 之前加熱混合粉末，能夠去除大部分之在混合粉末中所含 的C、H、0，因此能夠防止使用脂肪酸鹽或硫酸烷酯鹽 粉末等之含有鹼金屬之有機物，而導致雜質混入Cu-Ga合 金濺鍍靶。 另外，作爲其他之使濺鑛靶中含有鹼金屬的方法，係 有例如於原料中添加鹼金屬之氟化物的方法，但此方法氟 會作爲雜質而混入光吸收層，因此可能會對太陽電池之特 -11 - 201221660 性帶來不良影響。然而，上述之本發明中，因爲能夠去除 於脂肪酸鹽或硫酸烷酯鹽粉末中所含之C、H、0，故雜 質不會混入光吸收層，不會對太陽電池的特性帶來不良影 響。 於混合粉末燒結後，藉由實施機械加工與對背板之接 合，能夠得到濺鍍靶。 如以上所述，Cu-Ga合金濺鍍靶之製造方法中，藉由 不使用反應性高的鹼金屬單質，而使用脂肪酸鹽或硫酸烷 酯鹽等之含有鹼金屬之有機物，能夠不發熱而輕易地使 Cu-Ga合金濺鍍中含有鹼金屬。又，此Cu-Ga合金濺鍍 靶之製造方法中，藉由使用硫酸烷酯鹽等，除了鹼金屬以 外亦可含有硫，因此能夠將結晶組織保持微細，且能夠輕 易地製造均勻且高密度的濺鍍靶。 進一步，此Cu-Ga合金濺鍍靶之製造方法中，藉由在 燒結混合粉末之前加熱，能夠去除在脂肪酸鹽或硫酸烷酯 鹽等之含有鹼金屬之有機物中含有的鹼金屬或硫以外之 C、H、0，且能夠防止雜質混入Cu-Ga合金濺鍍靶。 又進一步地，此Cu-Ga合金濺鍍靶之製造方法中，藉 由調整濺鍍靶中含有之鹼金屬的濃度’能夠控制光吸收層 中之鹼金屬的濃度。 由如以上之製造方法而得的Cu-Ga合金濺鍍靶’係至 少含有Cu-Ga合金、與〇·〇1〜5質量％之鹼金屬。具體而 言，Cu-Ga合金濺鍍靶中，鎵濃度爲45質量％以下、鈉等 鹼金屬之含量爲〇.〇1~5質量％、剩餘部分爲銅及不可避免 -12- 201221660 的雜質構成。藉由使Cu-Ga合金濺鍍靶中，鎵含量爲45 質量％以下、鹼金屬含量爲在〇.〇1〜5質量％之範圍，太陽 電池之光吸收層中會適量地含有所含之鹼金屬，並具有經 抑制因鎵的溶融所造成之液相的產生之均勻組織，且不會 有破裂等缺陷。 再者，此Cu-Ga合金灘鍍耙，於Cu-Ga合金及鹼金 屬之外，亦可含有硫。藉由含有硫，Cu-Ga合金濺鍍靶會 將結晶組織保持微細，成爲更均勻且高密度。硫的含量爲 0.01 ~5質量％。Cu-Ga合金濺鍍靶係藉由含有0.01〜5質量 %之硫，可因硫而使結晶組織保持微細，成爲更均勻且高 密度。 如以上所述，藉由以上述製造方法來製造Cu-Ga合金 濺鍍靶，係不含有使用脂肪酸鹽或硫酸烷酯鹽等之含有鹼 金屬之有機物而造成的雜質，且因預先添加鹼金屬或硫， 因此能夠輕易地製造含鹼金屬之太陽電池的光吸收層。因 此，於製造太陽電池之光吸收層時，藉由使用此Cu-Ga合 金濺鍍靶’即不須設有用以使鹼金屬對光吸收層擴散的鹼 前驅物，在產業上亦爲有利。 [實施例] 以下，說明應用本發明之具體實施例，但本發明並不 受該等實施例所限定。 (實施例1) -13- 201221660 實施例1中，含有鎵（Ga)30質量％、剩餘部分爲銅 (Cu)及不可避免的雜質所構成，於平均粒徑爲1〇〇μηι之 Cu-Ga合金粉末lOOOg中，於燒結後、亦即所製造之Cu-Ga合金濺鍍靶中，混合硫酸月桂酯鈉I88g，使得鈉含有 1. 5質量％，而作爲原料粉末。 接著’爲了以熱壓燒結此原料粉末1 1 8 8 g，則塡充於 石墨模中。熱壓的溫度程式，係5 0 0 °C、保持5小時後， 於7 0 0 °C保持1小時。又，加壓係於維持5 0 0 °C終了後開 始。壓力設爲200kg/cm2、環境爲氬氣。將所得之熱壓體 加工’作爲Cu-Ga合金濺鍍靶。Cu-Ga合金濺鍍靶中係含 有1.8質量％的硫。 (實施例2) 實施例2中’除了使Cu_Ga合金粉末中之Ga濃度爲 1質量％以外，係以與實施例1相同的方法來製造C u - G a 合金濺鍍靶。 (實施例3) 實施例3中，除了使Cu_ga合金粉末中之Ga濃度爲 4 5質量％以外’係以與實施例！相同的方法來製造c u - G a 合金濺銨靶。 (實施例4) 實施例4中’除了使鈉濃度爲〇 〇1質量。以外，係以 201221660 與實施例1相同的方法來製造Cu_Ga合金濺鍍靶。Cu-Ga 合金濺鑛靶中係含有0.01質量％的硫。 (實施例5) 實施例5中，除了使用硫酸月桂酯鈉與脂肪酸鈉作爲 含有鹼金屬之物，且使鈉含有5質量％、硫含有5質量％ 以外’係以與實施例1相同的方法來製造Cu-Ga合金濺鍍 IE。 (實施例6) 實施例6中，除了使用聚氧乙烯月桂醚硫酸鈉作爲含 有鹼金屬之有機物，且使鈉含有0.5質量％以外，係以與 實施例1相同的方法來製造Cu-Ga合金濺鍍靶。Cu-Ga合 金濺鍍靶中係含有0.6質量％的硫。 (實施例7) 實施例7中，除了使用磺基琥珀酸二烷酯鈉作爲含有 鹼金屬之有機物，且使鈉含有1 .5質量％以外，係以與實 施例1相同的方法來製造Cu-Ga合金濺鍍靶。 (實施例8) 實施例8中，除了使用硫酸月桂酯鈉與脂肪酸鈉作爲 含有鹼金屬之有機物，且使鈉含有1 .5質量％、硫含有 0.01質量％以外，係以與實施例1相同的方法來製造Cu- -15- 201221660In the method for producing a Cu-Ga alloy sputtering target, a mixed powder obtained by mixing the above-mentioned Cu-Ga alloy powder and an organic substance containing an alkali metal is used as a raw material powder. This mixed powder is produced by mixing a Cu-Ga alloy powder with an organic substance containing an alkali metal so as to contain 0.01 to 5% by mass of an alkali metal in the produced Cu-Ga alloy sputtering target. For example, when the alkali metal is sodium, the Cu-Ga alloy sputtering target to be produced is mixed with Cu-Ga alloy powder by mixing sodium alkoxide or the like so as to contain 0.01 to 5% by mass of sodium. powder. When the content of sodium in the sputtering target to be produced is less than 0.01% by mass, it is in the same state as in the case where a light absorbing layer is formed by using a sputtering target to which no sodium is added, and when it exceeds 5% by mass, it is in production. The Cu-Ga alloy sputtering target produces a cracked state. Therefore, a mixed powder was produced in a manner that the sodium content of -9 - 201221660 was 0.01 to 5% by mass in the manufactured Cu-Ga alloy sputtering target. For the same reason, the mixed powder is produced in such a manner that the content of the Cu-Ga alloy sputtering target produced is 〇·〇1 to 5 mass% for the same reason. Here, it should be noted that the Cu-Ga alloy sputtering target can be produced by sintering the mixed powder as described later, and therefore it is necessary to consider an alkali metal-containing organic substance such as an alkyl sulfate salt powder. The mixed powder is produced by the weight reduction due to thermal decomposition. Here, in the case of producing a Cu-Ga alloy sputtering target, when sulfur is contained in the sputtering target, sulfur maintains a fine crystal structure and has a function of obtaining a uniform and high-density sputtering target. Therefore, it is preferred to contain sulfur in the raw material of the Cu-Ga alloy sputtering target. The sulfur component is preferably contained in the range of 0.01 to 5% by mass in the Cu-Ga alloy sputtering target to be produced. When the amount is less than 0.01% by mass, the crystal structure cannot be kept fine. When the amount is more than 5% by mass, the density of the target is lowered. Therefore, by setting the content of the sulfur component in the Cu-Ga alloy sputtering target to be in the range of 1 to 5 mass%, the crystal structure can be kept fine and a high-density target can be obtained. When a Cu-Ga alloy sputtering target is produced, the Cu-Ga alloy can be adjusted by adjusting the mixing ratio of an alkali metal-containing organic compound containing no alkali or sulfur and an alkali metal containing no sulfur. The ratio of alkali metal to sulfur contained in the sputtering target. Examples of the organic metal-containing organic substance containing no sulfur include fatty acid salts such as sodium fatty acid. The content of the alkali metal and sulfur can be measured by an atomic absorption spectrometer or an ICP (Inductively Coupled Plasma) spectroscopic analyzer, -10- 201221660. A method of producing a Cu-Ga alloy sputtering ruthenium is obtained by heating a mixed powder of a Cu-Ga alloy powder containing gallium and copper and an organic substance containing an alkali metal, followed by sintering. Specifically, the heating step before sintering is performed by heating the mixed powder in a vacuum or an inert atmosphere at 300 to 600 ° C to remove volatile components. By this heating step, most of C, cerium, and lanthanum in the alkali metal-containing organic substance such as a fatty acid salt or an alkyl sulfate salt volatilize without remaining in the produced Cu-Ga alloy sputtering target. If this heating is not carried out at 00 to 600 ° C, the volatile components remain in the Cu-Ga alloy sputtering target. After the mixed powder is heated, the mixed powder is sintered at 600 to 900 ° C under a pressure of 40 kg/cm 2 or more under vacuum or an inert atmosphere to obtain a sputtering target. This heating and sintering step can be carried out by a heating and sintering process using a pressure sintering furnace, and it is also possible to use two devices of a degreasing furnace and a pressure sintering furnace to perform heating and sintering in different apparatuses. In the method for producing a Cu-Ga alloy sputtering target, by heating the mixed powder before sintering, most of the C, H, and 0 contained in the mixed powder can be removed, thereby preventing the use of a fatty acid salt or an alkyl sulfate. An alkali metal-containing organic substance such as an ester salt powder causes impurities to be mixed into the Cu-Ga alloy sputtering target. Further, as another method of containing an alkali metal in the sputtering target, for example, a method of adding an alkali metal fluoride to a raw material is used. However, since fluorine is mixed as an impurity into the light absorbing layer, it may be a solar cell. -11 - 201221660 Sexually adverse effects. However, in the above-mentioned invention, since C, H, and 0 contained in the fatty acid salt or the alkyl sulfate salt powder can be removed, impurities do not mix into the light absorbing layer, and the characteristics of the solar cell are not adversely affected. . After the mixed powder is sintered, a sputtering target can be obtained by performing mechanical processing and bonding to the back sheet. As described above, in the method for producing a Cu-Ga alloy sputtering target, by using an alkali metal-containing organic substance such as a fatty acid salt or an alkyl sulfate salt without using a highly reactive alkali metal element, it is possible to prevent heat generation. The Cu-Ga alloy is easily sputtered with an alkali metal. In addition, in the method for producing a Cu-Ga alloy sputtering target, sulfur can be contained in addition to the alkali metal by using an alkyl sulfate salt or the like, so that the crystal structure can be kept fine, and uniform and high density can be easily produced. Sputter target. Further, in the method for producing a Cu-Ga alloy sputtering target, it is possible to remove an alkali metal or sulfur contained in an alkali metal-containing organic substance such as a fatty acid salt or an alkyl sulfate salt by heating before sintering the mixed powder. C, H, 0, and can prevent impurities from being mixed into the Cu-Ga alloy sputtering target. Further, in the method for producing a Cu-Ga alloy sputtering target, the concentration of the alkali metal in the light absorbing layer can be controlled by adjusting the concentration of the alkali metal contained in the sputtering target. The Cu-Ga alloy sputtering target obtained by the above production method is an alkali metal containing at least Cu-Ga alloy and 1 to 5 mass% of ruthenium. Specifically, in the Cu-Ga alloy sputtering target, the gallium concentration is 45 mass% or less, the alkali metal content such as sodium is 〇.〇1 to 5% by mass, the balance is copper, and the impurity is inevitable -12-201221660. Composition. When the Cu-Ga alloy is sputtered into the target, the gallium content is 45% by mass or less, and the alkali metal content is in the range of 〜1 to 5% by mass, and the light absorbing layer of the solar cell contains an appropriate amount. Alkali metal, and has a uniform structure that suppresses the generation of a liquid phase caused by the melting of gallium, and does not have defects such as cracking. Further, the Cu-Ga alloy beach is ruthenium-plated, and may contain sulfur in addition to the Cu-Ga alloy and the alkali metal. By containing sulfur, the Cu-Ga alloy sputtering target keeps the crystal structure fine and becomes more uniform and high density. The sulfur content is 0.01 to 5% by mass. The Cu-Ga alloy sputtering target system contains 0.01 to 5% by mass of sulfur, and the crystal structure can be kept fine by sulfur to have a more uniform and high density. As described above, the Cu-Ga alloy sputtering target is produced by the above-described production method, and does not contain impurities caused by using an alkali metal-containing organic substance such as a fatty acid salt or an alkyl sulfate salt, and the alkali metal is added in advance. Or sulfur, so that the light absorbing layer of the alkali metal-containing solar cell can be easily produced. Therefore, in the production of the light absorbing layer of a solar cell, it is industrially advantageous to use the Cu-Ga alloy sputtering target ‘that is, it is not necessary to provide an alkali precursor for diffusing the alkali metal to the light absorbing layer. [Examples] Hereinafter, specific examples of the application of the present invention will be described, but the present invention is not limited by the examples. (Example 1) -13-201221660 In Example 1, the content of gallium (Ga) was 30% by mass, and the remainder was copper (Cu) and unavoidable impurities, and the Cu-particle having an average particle diameter of 1 〇〇μηι was used. 5质量百分比为为原料质量。 In the after-sintering, that is, in the Cu-Ga alloy sputtering target, the sodium lauryl sulfate sodium I88g was mixed, so that the sodium contained 1.5% by mass, as a raw material powder. Next, in order to sinter the raw material powder 1 1 8 8 g by hot pressing, it was filled in a graphite mold. The hot pressing temperature program was maintained at 500 ° C for 5 hours and then maintained at 700 ° C for 1 hour. Further, the pressurization is started after the end of the maintenance of 500 °C. The pressure was set to 200 kg/cm2 and the environment was argon. The obtained hot press was processed as a Cu-Ga alloy sputtering target. The Cu-Ga alloy sputtering target contained 1.8% by mass of sulfur. (Example 2) A Cu-G a alloy sputtering target was produced in the same manner as in Example 1 except that the Ga concentration in the Cu-Ga alloy powder was 1% by mass. (Example 3) In Example 3, except that the Ga concentration in the Cu_ga alloy powder was 45 mass%, it was the same as in the examples! The same method was used to fabricate a cu-G a alloy splash target. (Example 4) In Example 4, except that the sodium concentration was 〇 〇 1 by mass. A Cu_Ga alloy sputtering target was produced in the same manner as in Example 1 in 201221660. The Cu-Ga alloy splash target contains 0.01% by mass of sulfur. (Example 5) In the same manner as in Example 1, except that sodium lauryl sulfate and sodium fatty acid were used as the alkali metal-containing substance, and sodium was contained in an amount of 5% by mass and sulfur was contained in an amount of 5% by mass. To manufacture Cu-Ga alloy sputtering IE. (Example 6) A Cu-Ga alloy was produced in the same manner as in Example 1 except that polyoxyethylene lauryl ether sulfate was used as the organic substance containing an alkali metal and sodium was contained in an amount of 0.5% by mass. Sputter target. The Cu-Ga alloy sputtering target contained 0.6% by mass of sulfur. (Example 7) In Example 7, Cu was produced in the same manner as in Example 1 except that sodium dialkyl sulfosuccinate was used as the organic substance containing an alkali metal and sodium was contained in an amount of 1.5% by mass. -Ga alloy sputtering target. (Example 8) In Example 8, except that sodium lauryl sulfate and sodium fatty acid were used as the organic substance containing an alkali metal, and sodium was contained in an amount of 1.5% by mass and sulfur was contained in an amount of 0.01% by mass, it was the same as in Example 1. Way to make Cu- -15- 201221660
Ga合金濺鍍靶。 (實施例9) 實施例9中’除了使用硫酸月桂酯鈉與脂肪酸鈉作爲 含有鹼金屬之有機物’且使鈉含有5質量％、硫含有〇.〇1 質量％以外，係以與實施例1相同的方法來製造Cu-Ga合 金濺鍍靶。 (實施例10) 實施例10中’除了使用脂肪酸鈉作爲含有鹼金屬之 有機物’且使鈉含有0.0 1質量％以外，係以與實施例丨相 同•的方法來製造Cu-Ga合金灘鍍耙。另外，實施例1〇 中，Cu-Ga合金濺鍍靶中不含有硫。 (實施例1 1) 實施例1 1中’除了使用脂肪酸鈉作爲含有鹼金屬之 有機物，且使鈉含有5質量％以外，係以與實施例1相同 的方法來製造Cu-Ga合金濺鍍靶。另外，實施例n中， Cu-Ga合金灘鍍靶中不含有硫。 (比較例1) 比較例1中’含有Ga 3 0質量％，剩餘部分爲Cu與 不可避免的雜質所構成，於平均粒徑爲1〇()μιη之Cu-Ga 合金粉末中’於燒結後、亦即於Cu-Ga合金濺鍍靶中混合 201221660 金屬鈉’使得鹼金屬含有丨·5質量％，而作爲原料粉末。 比較例1中，因爲金屬鈉混入原料粉末，故與空氣中 的水分反應’使混合粉末發熱。比較例1中，產生了因發 熱而無法繼續作業的缺陷。 (比較例2) 比較例2中’混合並溶解各別之原料，使其成爲由 G a 3 0質量％、金屬鈉1 .5質量％、剩餘部分爲c u及不可 避免的雜質所構成。 比較例2中，因爲金屬鈉混入原料粉末，故與空氣中 的水分反應’使原料發熱。 (比較例3) 比較例3中，除了使鈉、硫含有6質量％以外，係以 與實施例1相同的方法來製造Cu-Ga合金濺鍍靶。其結 果’ Cu-G a合金濺鍍靶在機械加工的階段產生了破裂之缺 陷。 於以下表1顯示實施例1〜實施例1 1、比較例1〜比較 例3之主要組成、含有鹼金屬之有機物、發熱及Cu-Ga合 金濺鍍靶破裂的有無。另外，鹼金屬之含量係使用 Jarrell-Ash公司製之原子吸光分析裝置AA —8200、硫之 含量係使用島津製造所股份有限公司之ICP發光分光分析 裝置ICPS-8000作爲分析裝置來測定。 -17- 201221660 [表1]Ga alloy sputtering target. (Example 9) In Example 9, except that sodium lauryl sulfate and sodium fatty acid were used as the organic substance containing an alkali metal, and sodium was contained in an amount of 5% by mass and sulfur was contained in an amount of 〇. The same method was used to fabricate a Cu-Ga alloy sputtering target. (Example 10) In Example 10, a Cu-Ga alloy beach ruthenium was produced by the same method as in Example ' except that sodium fatty acid was used as the organic substance containing an alkali metal and sodium was contained in an amount of 0.01% by mass. . Further, in Example 1A, the Cu-Ga alloy sputtering target does not contain sulfur. (Example 1 1) In Example 1 1 , a Cu-Ga alloy sputtering target was produced in the same manner as in Example 1 except that sodium fatty acid was used as the organic substance containing an alkali metal and sodium was contained in an amount of 5% by mass. . Further, in Example n, the Cu-Ga alloy beach plating target did not contain sulfur. (Comparative Example 1) In Comparative Example 1, 'containing Ga 3 0% by mass, the remainder being Cu and unavoidable impurities, in the Cu-Ga alloy powder having an average particle diameter of 1 〇 () μη' after sintering That is, the 201221660 metal sodium was mixed in the Cu-Ga alloy sputtering target so that the alkali metal contained 丨·5% by mass as a raw material powder. In Comparative Example 1, since sodium metal was mixed with the raw material powder, it reacted with moisture in the air to cause the mixed powder to generate heat. In Comparative Example 1, there was a defect that the operation could not be continued due to heat generation. (Comparative Example 2) In Comparative Example 2, the respective raw materials were mixed and dissolved to have an amount of G a 30% by mass, metallic sodium of 1.5% by mass, and the remainder being c u and unavoidable impurities. In Comparative Example 2, since sodium metal was mixed with the raw material powder, it reacted with moisture in the air to cause the raw material to generate heat. (Comparative Example 3) A Cu-Ga alloy sputtering target was produced in the same manner as in Example 1 except that sodium and sulfur were contained in an amount of 6% by mass. As a result, the Cu-G a alloy sputtering target has a defect of cracking at the stage of machining. The main components of Examples 1 to 1 1 and Comparative Examples 1 to 3, the organic materials containing an alkali metal, heat generation, and the presence or absence of cracking of the Cu-Ga alloy sputtering target are shown in Table 1 below. Further, the content of the alkali metal was measured by using an atomic absorption spectrometer AA-8200 manufactured by Jarrell-Ash Co., Ltd., and the sulfur content was measured using an ICP emission spectroscopic analyzer ICPS-8000 manufactured by Shimadzu Corporation. -17- 201221660 [Table 1]
Ga量 /質量％ 鹸金屬添加量/ 質量％ 硫量 /質量％ 含有鹸金屬之有機物 發熱 靶破裂 實施例1 30 1.5 1.8 硫酸月桂酯鈉 無 JhtT 撕 實施例2 1.5 1.6 硫酸月桂酯鈉 無 Jhrr 無 K施例3 45 1.5 1.8 硫酸月桂酯鈉 撕 無 實施例4 30 0.01 0.01 硫酸月桂酷鈉 無 無 實施例5 30 5 5 硫酸月桂酯鈉 脂肪酸鈉 «frrC m 無 實施例6 30 0.5 0.6 聚氧乙烯月桂醚硫酸鈉 無 Jhrr 撕 實施例7 30 1.5 1.8 磺基號珀酸二烷酯鈉 無 Λητ. 撕 實施例8 30 1.5 0.01 硫酸月桂酯鈉 脂肪酸鈉 無 無 贵施例3 30 5 0.01 硫酸月桂酯鈉 脂肪酸鈉 無 無 實施例10 30 0.01 0 脂肪酸鈉 無 Jhrr. Μ 實施例11 30 5 0 脂肪酸鈉 無 無 比較例1 30 1.5 0 金屣鈉 有 - 比較例2 30 1.5 0 金屬鈉 有 - 比較例3 30 6 6 硫酸月桂酯鈉 Anr. m 有 如表1所示，實施例1〜實施例11中，藉由不使用金 屬鈉，而使用硫酸月桂酯鈉或脂肪酸鈉等之含有鹼金屬之 有機物，於製造Cu-Ga合金濺鍍靶時不產生發熱。 相對於該等實施例，比較例1及比較例2中，因爲使 用了金屬鈉，故於製造濺鍍靶時會發熱，而產生無法繼續 作業之缺陷。又，如比較例1所示’即使使用了 c u -G a合 金粉末，或如比較例2所示即使不使用Cu-Ga合金粉末’ 而混合G a、C u及金屬鈉時，由於使用了金屬鈉’故產生 -18- 201221660 發熱。又，比較例3中，鹼金屬之含量爲6質量％，因爲 鹼金屬之含量多，故Cu-Ga合金濺鍍靶產生破裂。 由以上之實施例及比較例，可知在製造含有鹼金屬之 Cu-Ga合金濺鍍靶時，藉由使用含有鹼金屬之有機物，能 夠在不發熱、且不產生Cu-Ga合金濺鍍靶之破裂等缺陷 下，容易地製造含有鹼金屬之Cu-Ga合金濺鍍靶。 -19-Ga amount/mass% 鹸 metal addition amount/mass% sulphur content/mass% Organic matter heat-generating target rupture Example 1 30 1.5 1.8 Sodium lauryl sulfate without JhtT Tear Example 2 1.5 1.6 Sodium lauryl sulfate without Jhrr None K Example 3 45 1.5 1.8 Sodium lauryl sulfate torn without Example 4 30 0.01 0.01 Lauric sodium sulfate No Example 5 30 5 5 Sodium lauryl sulfate sodium fatty acid «frrC m No Example 6 30 0.5 0.6 Polyoxyethylene Sodium lauryl ether sulfate without Jhrr tearing Example 7 30 1.5 1.8 Sodium sulfo-sodium sulfonate without Λητ. Tear Example 8 30 1.5 0.01 Sodium lauryl sulfate sodium fatty acid No expensive Example 3 30 5 0.01 Lauryl sulfate Sodium fatty acid sodium No Example 10 30 0.01 0 Fatty acid sodium without Jhrr. 实施 Example 11 30 5 0 Fatty acid sodium No Comparative Example 1 30 1.5 0 Gold strontium sodium - Comparative Example 2 30 1.5 0 Metal sodium has - Comparative Example 3 30 6 6 sodium lauryl sulfate Anr. m As shown in Table 1, in Examples 1 to 11, the use of alkali metal containing sodium lauryl sulfate or sodium fatty acid was used without using sodium metal. Was manufactured in the Cu-Ga alloy does not generate heat when the sputtering target. With respect to these examples, in Comparative Example 1 and Comparative Example 2, since metallic sodium was used, heat was generated when the sputtering target was produced, and the defect that the operation could not be continued was caused. Further, as shown in Comparative Example 1, even if cu-G a alloy powder was used, or as shown in Comparative Example 2, G a, Cu and metallic sodium were mixed without using Cu-Ga alloy powder, Metal sodium 'produces -18- 201221660 fever. Further, in Comparative Example 3, the content of the alkali metal was 6% by mass, and since the content of the alkali metal was large, the Cu-Ga alloy sputtering target was cracked. From the above examples and comparative examples, it is understood that when an alkali metal-containing Cu-Ga alloy sputtering target is produced, by using an organic substance containing an alkali metal, it is possible to generate no Cu-Ga alloy sputtering target without generating heat. An alkali metal-containing Cu-Ga alloy sputtering target is easily produced under defects such as cracking. -19-