TW201342651A - Improved method for forming metal contacts - Google Patents

Abstract

Methods of forming metal contacts with metal inks in the manufacture of photovoltaic devices are disclosed. The metal inks are selectively deposited on semiconductor coatings by inkjet and aerosol apparatus. The composite is heated to selective temperatures where the metal inks burn through the coating to form an electrical contact with the semiconductor. Metal layers are then deposited on the electrical contacts by light induced or light assisted plating.

Description

用於形成金屬接觸之改良方法 Improved method for forming metal contacts

本發明申請案主張依35 U.S.C.§119(e)要求享有於2010年10月14日向美國申請之臨時申請案第61/393,295號優先權，並將該案全文納入本案作為參考。 The present application claims the benefit of 35 U.S.C. § 119(e), the Provisional Application No. 61/393,295, filed on Jan. 14, 2010, the entire disclosure of which is incorporated herein by reference.

美國政府依據美國能源部及為國家再生能源實驗室合約操作者之永續能源聯盟，LLC間之編號DE-AC36-08GO28308合約，於本發明享有權利。 The U.S. government has rights under this invention in accordance with the U.S. Department of Energy and the Sustainable Energy Alliance for the National Renewable Energy Laboratory Contract Operator, LLC-DE36-GO36-08 contract.

半導體之以金屬為基底之接觸(如在光伏裝置中者)涉及於半導體前側(或是半導體經入射光照射之側)及背側(或是未被入射光照射之側)之電性傳導接觸之形成。該金屬塗層建立與半導體之歐姆接觸，致使電荷載體自該半導體射出至該電性傳導接觸，而無損失且有長生命期。為了避免電流損失，金屬化柵狀接觸具有適合的導電性，例如，高傳導性或足夠高之導體軌道截面。 Metal-based contact of semiconductors (as in photovoltaic devices) involves electrical conduction contacts on the front side of the semiconductor (or the side of the semiconductor that is illuminated by the incident light) and the back side (or the side that is not illuminated by the incident light). Formation. The metal coating establishes an ohmic contact with the semiconductor such that the charge carrier exits the semiconductor to the electrically conductive contact without loss and long life. In order to avoid current losses, the metallized grid contact has a suitable conductivity, for example a high conductivity or a sufficiently high conductor track cross section.

對於金屬塗覆太陽能電池之背側，有許多製程達到上述之要求。舉例而言，為了改良在該太陽能電池背側之電流傳導，增加於該背側正下方之p摻雜。通常，鋁係用於達成此目的。該鋁係藉由，舉例而言，由氣相沉積或由經印刷至該背側而被驅入或分別合金入而施加。當金屬塗覆該前側或被照射側時，該目標係達成最少量之主動半導體表面之遮蔽，以盡可能使用該表面以補捉光子。 For the back side of metal coated solar cells, there are a number of processes that meet the above requirements. For example, to improve current conduction on the back side of the solar cell, p-doping is added directly below the back side. Usually, aluminum is used for this purpose. The aluminum is applied by, for example, vapor deposition or by being driven into or printed separately onto the back side. When the metal is coated on the front side or the illuminated side, the target achieves a minimum amount of shadowing of the active semiconductor surface to use the surface as much as possible to capture photons.

用於商業上形成該太陽能電池中之前側接觸之方法係 該藉絲網印刷施加金屬糊料。該糊料含有金屬粒子(典型上為銀)以提供電性傳導性，以及含有玻料(glass frit)、流變改質劑、及高沸點溶劑，如萜品醇。於印刷之後，乾燥該電池，及之後典型上於溫度範圍為自約600至1000℃在帶狀爐中燒製(fire)。一但燒製，該玻料將與該前側之抗反射塗層(典型上係矽氮化物)反應(或「燒穿(burn-through)」)及幫助提供接著至該電池。絲網印刷糊料之使用係工業標準但卻有缺點。絲網印刷係接觸印刷方法，其須要對易碎矽太陽能電池大量處理，而導致明顯量之意外破損。其亦產生化學廢棄物、都市廢棄物、以及破損絲網之額外花費。結果，製造時可產生之最小線寬被絲網技術物理性限制在約80至100微米之範圍。在實驗室中由絲網印刷所得之較小線寬係可為物理上可能者，但現時卻較難以達成大量生產。 Method for commercially forming front side contact in the solar cell The screen printing is applied with a metal paste. The paste contains metal particles (typically silver) to provide electrical conductivity, as well as a glass frit, a rheology modifier, and a high boiling solvent such as terpineol. After printing, the battery is dried and then typically fired in a belt furnace at a temperature ranging from about 600 to 1000 °C. Once fired, the glass will react (or "burn-through") with the front side anti-reflective coating (typically tantalum nitride) and help provide the battery to the cell. The use of screen printing pastes is an industry standard but has drawbacks. Screen printing is a contact printing method that requires extensive processing of fragile tantalum solar cells, resulting in significant amounts of accidental breakage. It also generates additional costs for chemical waste, municipal waste, and damaged wire mesh. As a result, the minimum line width that can be produced at the time of manufacture is physically limited by the screen technology to a range of about 80 to 100 microns. Smaller line widths obtained by screen printing in the laboratory may be physically possible, but it is currently difficult to achieve mass production.

用於製造該前側接觸較複雜之製程，係使用雷射或光微影技術定義出電流軌道結構。現時這些技術可製造較窄的線，卻犧牲了總處理量。接著，該電流軌道被金屬化。一般而言，常使用多種金屬塗覆步驟以施加該金屬塗層而企圖達到足夠之接著(adhensive)強度及所欲之厚度以提供電性傳導性。舉例而言，當使用濕化學金屬塗覆程序時，第一精細金屬塗層係藉由鈀催化劑手段沉積於該電流軌道上。其又經常以鎳之無電沉積加以強化。為了增加該傳導性，可將銅藉由無電或電解沉積沉積於該鎳上。接著，該銅可塗覆錫或銀之精細層以防護氧化。 The process for manufacturing the front side contact is complicated, and the current track structure is defined by laser or photolithography. At present, these technologies can make narrower lines, but at the expense of total processing. The current track is then metallized. In general, a variety of metal coating steps are often employed to apply the metal coating in an attempt to achieve sufficient strength and desired thickness to provide electrical conductivity. For example, when a wet chemical metal coating procedure is used, the first fine metal coating is deposited on the current track by means of a palladium catalyst. It is often reinforced with electroless deposition of nickel. To increase this conductivity, copper can be deposited on the nickel by electroless or electrolytic deposition. The copper can then be coated with a fine layer of tin or silver to protect against oxidation.

或者，電流軌道可用光誘導鍍覆製程金屬化。此金屬化製程涉及使用傳統之印刷方法先金屬化太陽能電池之背側，及於惰氣環境下燒結電性傳導糊料。該等糊料可包含銀、鋁和玻璃料以及有機黏合劑。該糊料中其他金屬如鎳、鈀、銅、鋅及錫亦可燒入。該太陽能電池前側經矽氧化物或矽氮化物之鈍化或抗反射層板塗覆。電流軌道之凹槽係形成抗反射層板中並延伸至半導體。凹槽可用光微影、雷射寫入或機械侵蝕加以形成。之後，該前側之電流軌道係藉由光誘導鍍覆而鍍覆鎳。將該太陽能電池置於鎳鍍覆浴中，且將光施加至該太陽能電池，且於約1至2分鐘後於該半導體材料上產生鎳層。為了強化，可將又一層金屬層(如銅)直接產生於此鎳層上。該銅層可藉由將銀或錫薄層施加至該銅層板上以防止氧化。 Alternatively, the current track can be metallized using a light inducing plating process. This metallization process involves first metallizing the back side of the solar cell using conventional printing methods and sintering the electrically conductive paste in an inert gas environment. The pastes may comprise silver, aluminum and glass frits as well as organic binders. Other metals such as nickel, palladium, copper, zinc and tin may be burned in the paste. The front side of the solar cell is coated with a passivation or anti-reflective laminate of tantalum oxide or tantalum nitride. The grooves of the current track are formed in the anti-reflective laminate and extend to the semiconductor. The grooves can be formed by photolithography, laser writing or mechanical erosion. Thereafter, the front side current track is plated with nickel by photoinduced plating. The solar cell is placed in a nickel plating bath and light is applied to the solar cell, and a nickel layer is produced on the semiconductor material after about 1 to 2 minutes. For reinforcement, another layer of metal, such as copper, can be directly produced on the nickel layer. The copper layer can be prevented from oxidizing by applying a thin layer of silver or tin to the copper layer.

另一種於太陽能電池上形成金屬接觸之方法係如下所示。利用雷射選擇性移除抗反射層的某些部分以曝露下方半導體材料而形成電流軌道。然而，雷射應用係為高成本，且一般而言低成本之方法於工業上較佳。將含有約20 nm至1000 nm範圍之金屬奈米粒子之油墨藉由噴墨或氣溶膠裝置施加至經曝露半導體材料。該裝置經加熱至溫度約100℃至900℃，持續自一秒至三十分鐘以趕掉所有溶劑及形成該金屬接觸。之後，這些接觸係藉由電鍍覆額外之金屬層而予以強化。 Another method of forming a metal contact on a solar cell is as follows. Some portions of the anti-reflective layer are selectively removed by laser exposure to expose the underlying semiconductor material to form a current track. However, laser applications are costly, and generally low cost methods are industrially preferred. An ink containing metal nanoparticles ranging from about 20 nm to 1000 nm is applied to the exposed semiconductor material by an inkjet or aerosol device. The apparatus is heated to a temperature of from about 100 ° C to 900 ° C for from one second to thirty minutes to purge off all of the solvent and form the metal contact. These contacts are then strengthened by electroplating an additional layer of metal.

雖然已有於半導體上形成金屬接觸之方法，但仍有於半導體上製造初始金屬接觸之改良方法之需求。 While there have been methods of forming metal contacts on semiconductors, there is still a need for improved methods of fabricating initial metal contacts on semiconductors.

本發明方法之一個實施例包含提供燒穿金屬油墨；選擇性施加該燒穿金屬油墨至半導體基板上之抗反射塗層；燒製該具有抗反射塗層之半導體基板及該燒穿金屬油墨以提供來自該燒穿金屬油墨之金屬與該半導體基板間之歐姆接觸；以及藉由光誘導鍍覆，於來自該燒穿金屬油墨之金屬上沉積一層或更多層金屬層。 An embodiment of the method of the present invention comprises providing a burn through metal ink; selectively applying the burn-through metal ink to an anti-reflective coating on the semiconductor substrate; firing the semiconductor substrate having the anti-reflective coating and the burn-through metal ink Providing ohmic contact between the metal from the burn through metal ink and the semiconductor substrate; and depositing one or more metal layers on the metal from the burn through metal ink by photoinduced plating.

該燒穿金屬油墨包含一種或更多種金屬源及一種或更多種試劑，該試劑於燒製時燒穿該抗反射塗層而使得該油墨之金屬可與該下方半導體形成歐姆接觸。添加劑諸如溶劑、界面活性劑、分散劑、黏合劑、錯合劑、還原劑、流變改質劑及螫合劑亦可被包含於該燒穿金屬油墨中。 The burn through metal ink comprises one or more sources of metal and one or more agents that burn through the anti-reflective coating upon firing such that the metal of the ink can make ohmic contact with the underlying semiconductor. Additives such as a solvent, a surfactant, a dispersant, a binder, a binder, a reducing agent, a rheology modifier, and a chelating agent may also be included in the burn through metal ink.

依該方法製造之該金屬接觸增加了半導體裝置之表現，且因此提供相較於許多具有可相比擬尺寸和單位面積之傳統半導體裝置來得增加之功率輸出。該方法使得能有精細線金屬接觸之形成，其減少遮蔽及增進入射光之吸收。該燒穿製程藉由消去於該金屬接觸之形成中之諸如光微影及雷射寫入之步驟而減少該半導體物件之製造中步驟之數量，以及減少材料破損，因而減少整體生產半導體裝置之成本。除此之外，對照許多傳統半導體裝置，形成金屬種晶層之該燒穿製程(其後跟隨著於種晶層上光誘導鍍覆額外金屬層)，提供該金屬層及該半導體表面間改良之歐姆接觸。 The metal contact fabricated in accordance with this method increases the performance of the semiconductor device and thus provides an increased power output compared to many conventional semiconductor devices having comparable dimensions and unit area. This method enables the formation of fine line metal contacts which reduce shadowing and enhance absorption of incident light. The burn-through process reduces the number of steps in the fabrication of the semiconductor article and reduces material damage by eliminating steps such as photolithography and laser writing in the formation of the metal contact, thereby reducing overall fabrication of the semiconductor device. cost. In addition, in contrast to many conventional semiconductor devices, the burn-through process for forming a metal seed layer (which is followed by photo-induced plating of additional metal layers on the seed layer) provides improved between the metal layer and the semiconductor surface. Ohmic contact.

於整個說明書中使用時，名詞「沉積」以及「鍍覆」可互換使用。名詞「電流軌道」、「電流線」及「金屬接觸」可互換使用。名詞「組成物」及「浴」可互換使用。不定冠詞「一(a)」及「一(an)」意欲包含單數及複數兩者。名詞「前側」意指該半導體晶圓被照射側或曝於入射光之側。名詞「背側」意指該半導體晶圓之未被照射側或不曝於入射光之側。名詞「選擇性沉積」意指金屬沉積發生於基板上特定所欲之區域。名詞「單位面積」及「表面面積」於整個說明書中可互換使用。名詞「歐姆接觸」係半導體裝置上被製備成使得該裝置之電流-伏特(I-V)曲線係線性且對稱之區域。名詞「肖特基接觸(Schottky contact)」係半導體裝置上使得該裝置之電流-伏特(I-V)曲線係非線性且非對稱之區域。全電池效率係由下式表示：η=P_m/E x A_c，其中P_m係指最大功率點，E係指入射光照度(單位為每平方公尺瓦特)，以及A_c係指太陽能電池之表面面積(單位為平方公尺)。名詞「燒製」意指使組成分融化或反應，且一般而言於溫度為或高於約400℃完成。 The terms "deposit" and "plating" are used interchangeably throughout the specification. The terms "current track", "current line" and "metal contact" are used interchangeably. The terms "composition" and "bath" are used interchangeably. The indefinite articles "a" and "an" are intended to include both singular and plural. The term "front side" means that the semiconductor wafer is illuminated or exposed to the side of the incident light. The term "back side" means the side of the semiconductor wafer that is not illuminated or that is not exposed to incident light. The term "selective deposition" means that metal deposition occurs in a specific desired area on a substrate. The terms "unit area" and "surface area" are used interchangeably throughout the specification. The term "ohmic contact" is a region on a semiconductor device that is prepared such that the current-volt (IV) curve of the device is linear and symmetrical. The term "Schottky contact" is a region on a semiconductor device that makes the current-volt (IV) curve of the device nonlinear and asymmetrical. The full cell efficiency is expressed by: η = P _m / E x A _c , where P _{m is the} maximum power point, E is the incident illuminance (in watts per square meter), and A _{c is the} solar cell Surface area (in square meters). The term "firing" means to melt or react a component, and is generally completed at a temperature of about or above about 400 °C.

除內文明確另有指示，如下縮寫具有如下意義：℃=攝氏溫度；g=公克；mL=毫升；L=公升；A=安培；dm=公寸；cm=公分；mm=公厘；μm=微米；nm=奈米；cP=厘泊=10^-2泊=10^-3帕斯卡秒；Hz=赫；kHz=千赫；UV=紫外線；IR=紅外線；以及SEM=掃描式電子顯微鏡。 Unless otherwise indicated in the text, the following abbreviations have the following meanings: °C = Celsius; g = g; mL = ml; L = liter; A = amperes; dm = inches; cm = cm; mm = mm; = micron; nm = nanometer; cP = centipoise = 10 ^{- 2} poise = 10 ^-3 Pascal seconds; Hz = Hz; kHz = kilohertz; UV = ultraviolet; IR = infrared; and SEM = scanning electron microscope.

除另有指示者，所有百分比及比例皆以重量計。所有數值範圍接包含上、下限值，除了此等數值範圍顯然受到 總和至多100%之限制外，餘皆可以任何序順組合使用。 All percentages and ratios are by weight unless otherwise indicated. All numerical ranges include upper and lower limits, except that these numerical ranges are obviously subject to In addition to the limit of up to 100%, the balance can be used in any order.

光伏裝置及太陽能電池可由單晶、多晶或非晶矽半導體晶圓組成，但不限於此。當以下所述有關於矽半導體晶圓時，亦可使用其他適當的半導體晶圓，諸如鎵-鉀化物、矽-鍺、鍺以及鎘-碲半導體。當使用矽晶圓時，其典型上具有p型基底摻雜(base doping)。 The photovoltaic device and the solar cell may be composed of a single crystal, polycrystalline or amorphous germanium semiconductor wafer, but are not limited thereto. Other suitable semiconductor wafers, such as gallium-potassium, ytterbium-tellurium, antimony, and cadmium-tellurium semiconductors, may also be used when referring to germanium semiconductor wafers as described below. When a germanium wafer is used, it typically has a p-type base doping.

該半導體晶圓可具有廣泛種類之維度及表面電阻率。該等晶圓維度包含，但不限於，圓型，方形或矩形之形狀或可為任何其他適當的形狀。該等晶圓於其未被照設側亦可具有交指金屬接觸。 The semiconductor wafer can have a wide variety of dimensions and surface resistivity. The wafer dimensions include, but are not limited to, a circular, square or rectangular shape or may be any other suitable shape. The wafers may also have interdigitated metal contacts on their untouched sides.

一般而言，該晶圓之背側係經金屬化以提供低電阻晶圓。該半導體晶圓之表面電阻，亦名為片電阻，之範圍可為自40至90歐姆/單位面積(ohm/square)，或如自40歐姆/單位面積至60歐姆/單位面積，或如自60歐姆/單位面積至80歐姆/單位面積。 In general, the back side of the wafer is metallized to provide a low resistance wafer. The surface resistance of the semiconductor wafer, also known as sheet resistance, can range from 40 to 90 ohms per unit area (ohm/square), or as from 40 ohms per unit area to 60 ohms per unit area, or as 60 ohms/unit area to 80 ohms/unit area.

本質上，全部背側可經金屬塗覆或該背側的一部分可經金屬塗覆，如形成網格者。該金屬化過程可由各種技術所提供，且可先於該晶圓前側之金屬化實施。於一具體實施例中，金屬塗層係以電性傳導糊料形式施加至該背側，該糊料諸如含銀糊料、含鋁糊料或含鋁及銀糊料；然而，亦可使用其他包含如鎳、鈀、銅、鋅或錫之金屬之糊料。該等導電糊料典型上包含導電導電粒子、玻料及有機黏合劑。導電糊料可藉由各種技術施加至該晶圓，例如絲網印刷。於施加糊料後，將其燒製以製造與矽之電性接觸且燒 去有機黏合劑。於燒製前，可視須要實施於較低溫度的乾燥步驟。當使用含有鋁之導電糊料時，該鋁係部分擴散入該晶圓背側，或若使用亦含銀之糊料時，可能與銀形成合金。該等含鋁糊料之使用可改良該電阻接觸及提供「p+」摻雜區。亦可藉由先施加鋁或硼並接著進行內擴散而製造高濃度摻雜「p+」型區。於一具體實施例中，可於進行未被照射側之金屬塗覆應用前施加和燒製含鋁糊料。來自經燒製含鋁糊料之殘餘物可視需要地於進行該金屬塗覆之應用前移除。於另一具體實施例中，種晶層可沉積於該晶圓背側上且可藉由無電或電解鍍覆將金屬塗層沉積於該種晶層上。 Essentially, all of the back side may be metal coated or a portion of the back side may be metal coated, such as forming a mesh. The metallization process can be provided by a variety of techniques and can be performed prior to metallization of the front side of the wafer. In a specific embodiment, the metal coating is applied to the back side in the form of an electrically conductive paste, such as a silver-containing paste, an aluminum-containing paste, or an aluminum-containing and silver paste; however, it can also be used. Other pastes containing metals such as nickel, palladium, copper, zinc or tin. The conductive paste typically comprises conductive conductive particles, a glass frit and an organic binder. The conductive paste can be applied to the wafer by various techniques, such as screen printing. After applying the paste, it is fired to make electrical contact with the crucible and burned. Go to the organic binder. It may be necessary to carry out a drying step at a lower temperature before firing. When a conductive paste containing aluminum is used, the aluminum portion partially diffuses into the back side of the wafer, or may be alloyed with silver if a silver paste is also used. The use of such aluminum-containing pastes improves the electrical resistance contact and provides a "p+" doped region. A high concentration doped "p+" type region can also be produced by first applying aluminum or boron followed by internal diffusion. In one embodiment, the aluminum-containing paste can be applied and fired prior to application to the metal coating on the unirradiated side. Residues from the fired aluminum-containing paste can optionally be removed prior to application for the metal coating. In another embodiment, a seed layer can be deposited on the back side of the wafer and a metal coating can be deposited on the seed layer by electroless or electrolytic plating.

該晶圓前側可視需要地進行結晶取向紋理蝕刻(crystal-oriented texture etching)以賦予該表面改良的光入射幾何結構(其減少反射)。為了製造半導體接面，於該晶圓前側發生磷擴散或鐵植入以產生n摻雜(n+或n++)區及提供具有PN接面之晶圓。該n摻雜區可視作為射極層。 The front side of the wafer can optionally undergo crystal-oriented texture etching to impart improved light incident geometry to the surface (which reduces reflection). In order to fabricate a semiconductor junction, phosphorus diffusion or iron implantation occurs on the front side of the wafer to create an n-doped (n+ or n++) region and to provide a wafer with a PN junction. The n-doped region can be regarded as an emitter layer.

抗反射塗層(ARC)或層係加至該晶圓之前側或射極層上。此外該抗反射層可作為鈍化層。適當的抗反射層包含，而不限於，矽氧化物層如SiO_x、矽氮化物層諸如Si₃N₄、或矽氧化物層及矽氮化物層之組合。典型上係用矽氮化物。於前述式中，x係氧原子數。典型上x係整數2。該抗反射層可藉由數種技術沉積，諸如藉由各種氣相沉積方法，舉例而言，化學氣相沉積及物理氣相沉積。 An anti-reflective coating (ARC) or layer is applied to the front side or the emitter layer of the wafer. Furthermore, the antireflection layer can serve as a passivation layer. Suitable anti-reflective layer comprises, without limitation, silicon oxide layers such as SiO _x, silicon nitride layer, or a combination of oxides such as Si ₃ N ₄ silicon nitride layer and the silicon layers. Typically, tantalum nitride is used. In the above formula, x is the number of oxygen atoms. Typically x is an integer of two. The antireflective layer can be deposited by several techniques, such as by various vapor deposition methods, for example, chemical vapor deposition and physical vapor deposition.

該晶圓前側含有金屬化圖案。該等金屬化圖案典型上 係集電線及電流匯流排；然而，其亦可包含，但不限於，離子化蝕刻圈線接觸。一般而言，集電線係典型上橫越該匯電條及典型上具有相對精細之結構，例如，相對於電流匯流排之維度。 The front side of the wafer contains a metallization pattern. The metallization patterns are typically The wires and current busbars are tied; however, they may also include, but are not limited to, ionized etched wire contacts. In general, the collection line typically traverses the bus bar and typically has a relatively fine structure, for example, relative to the dimensions of the current bus bar.

該金屬化圖案係藉由下述形成：利用燒穿金屬油墨(係使用常見之噴墨或氣溶膠裝置選擇性施加該油墨至該塗層或抗反射層)，接著燒製及光誘導鍍覆額外之金屬層而完成該電流軌道。該燒製或燒穿步驟導致在來自該燒穿油墨之金屬及位於該抗反射層下方之半導體晶圓間之牢固鍵結之形成。除此之外，該燒穿製程建立該半導體晶圓及該金屬間之歐姆接觸以及藉由光誘導鍍覆沉積之任何額外層。 The metallization pattern is formed by firing through a metallic ink (using a conventional inkjet or aerosol device to selectively apply the ink to the coating or antireflective layer) followed by firing and photoinduced plating. The current track is completed with an additional metal layer. The firing or burn-through step results in the formation of a strong bond between the metal from the ink-through ink and the semiconductor wafer underlying the anti-reflective layer. In addition, the burn through process establishes ohmic contact between the semiconductor wafer and the metal and any additional layers deposited by photoinduced plating.

利用噴墨及氣溶膠施加該燒穿金屬油墨係非接觸方法，致使該燒穿金屬油墨經施加而無須直接接觸裝置噴嘴及該半導體晶圓。此減少於製造製程中晶圓損傷的可能性。該燒穿金屬油墨利用噴墨抑或氣溶膠施加係允許窄電流軌道之形成，因而減少遮蔽且增加入射光吸收度，並同時使得能有更多待形成於該半導體晶圓上之電流軌道，進而增加輸出電流。電流軌道可小於或等於約75μm寬，且於另一種具體實施例中，可少於或等於約50μm寬，且於又另一種具體實施例中，可少於或等於約20μm至25μm寬。 The burn through metal ink non-contact method is applied by inkjet and aerosol, so that the burn through metal ink is applied without directly contacting the device nozzle and the semiconductor wafer. This reduces the likelihood of wafer damage during the manufacturing process. The burn through metal ink utilizes an ink jet or aerosol application system to allow the formation of a narrow current track, thereby reducing shadowing and increasing incident light absorbance, while at the same time enabling more current tracks to be formed on the semiconductor wafer, thereby Increase the output current. The current track may be less than or equal to about 75 [mu]m wide, and in another particular embodiment, may be less than or equal to about 50 [mu]m wide, and in yet another specific embodiment, may be less than or equal to about 20 [mu]m to 25 [mu]m wide.

該噴墨印刷法可為連續式噴墨法或控制液滴法(drop-on-demand method)。該連續式方法係一種藉由於該金屬油墨使用泵連續射出時調整電磁場以調整該金屬油墨方向之 印刷方法。該控制液滴法係只分注該金屬油墨於電子訊號有需求時之方法。控制液滴法可分成壓電油墨噴射法(其壓力係藉由使用壓電板產生，該壓電板造成隨電力產生機械改變)以及熱油墨噴射法(其使用由熱所造成之氣泡膨脹產生之壓力)。 The inkjet printing method may be a continuous inkjet method or a drop-on-demand method. The continuous method is to adjust the electromagnetic field to adjust the direction of the metal ink by continuously ejecting the metal ink using a pump. Printing method. The controlled droplet method is a method in which only the metal ink is dispensed when the electronic signal is required. The controlled droplet method can be divided into a piezoelectric ink jet method (the pressure is generated by using a piezoelectric plate which causes a mechanical change with electric power) and a thermal ink jet method (which uses a bubble expansion caused by heat). The pressure).

對比於該噴墨印刷法，該氣溶膠法首先形成該金屬油墨之氣溶膠。將該氣溶膠透過加壓噴嘴導引至該半導體基板且將該加壓噴嘴裝設於列印頭上。將該氣溶膠與聚焦氣體混合且以聚焦形式輸送至該加壓噴嘴。使用聚焦氣體來分注油墨係減少噴嘴堵塞的可能性且亦使較精細之電流軌道、較使用噴墨裝置所得者大之高寬比得以形成。於每程(per pass)印刷，該電流軌道之高寬比(高度/寬度)之範圍可於自約0.001至0.5，或例如自約0.002至0.4，或例如自約0.002至0.04。每程之高寬比愈高，該方法愈有效率。 In contrast to the ink jet printing method, the aerosol method first forms an aerosol of the metallic ink. The aerosol is guided to the semiconductor substrate through a pressurizing nozzle and the pressurizing nozzle is mounted on the printing head. The aerosol is mixed with a focusing gas and delivered to the pressurized nozzle in a focused form. The use of a focused gas to dispense the ink reduces the likelihood of nozzle clogging and also allows finer current tracks to be formed with greater aspect ratio than those obtained using ink jet devices. The aspect ratio (height/width) of the current track may range from about 0.001 to 0.5, or from about 0.002 to 0.4, or, for example, from about 0.002 to 0.04, per pass printing. The higher the aspect ratio of each pass, the more efficient the method.

於一具體實施例中，該燒穿金屬油墨係選擇性於空氣或惰氣環境(例如，氮氣或氬氣)中於室溫噴墨印刷於SiO_x或矽氮化物抗反射層板上。可用100 Hz至20000 Hz之液滴產生率，導致產生約0.02μm至10μm每程之沉積率。可由噴墨印刷多層得到較厚的沉積。 In one embodiment, the burn through metal ink is inkjet printed on a SiO _x or tantalum nitride antireflective sheet at room temperature in an air or inert atmosphere (eg, nitrogen or argon). A droplet production rate of from 100 Hz to 20,000 Hz can be used, resulting in a deposition rate of about 0.02 μm to 10 μm per pass. Thicker deposits can be obtained by ink jet printing of multiple layers.

該燒穿金屬油墨包含一種或多種之金屬、金屬前驅物、金屬有機前驅物、金屬錯合物、或金屬鹽類以提供該導電材料。該金屬油墨亦包含一種或多種之玻料、球磨或其他方式研磨之玻料、金屬有機前驅物、或金屬鹽類如該燒穿劑。典型上該導電材料及該燒穿劑係呈粒子形式。較 佳者，該燒穿金屬油墨包含金屬粒子及玻料粒子。 The burn through metal ink comprises one or more metals, metal precursors, metal organic precursors, metal complexes, or metal salts to provide the conductive material. The metallic ink also comprises one or more glass materials, ball milled or otherwise ground glass, metal organic precursors, or metal salts such as the burn-in agent. Typically the electrically conductive material and the burnthrough agent are in the form of particles. More Preferably, the burn through metal ink comprises metal particles and glass particles.

該粒子尺寸範圍可為自約5μm或更少，或例如自約0.1μm至1μm。較佳者，該粒子係奈米尺寸粒子。奈米尺寸粒子較更大維度者具有改善之表現，因為相較於較大之大型粒子，其單位質量之表面積增加，且其有著與較大直徑粒子不同之物理化學性質。典型上，該金屬奈米粒子直徑之範圍為自約1000 nm或更少，較佳者該金屬奈米粒子為自約25 nm至800 nm之範圍，且於另一種具體實施例中，自約100 nm至400 nm。金屬包含，但不限於，銀、銅、鎳、金、鈀及其鹽類及錯合物。典型上使用銀、銅，及鎳。可用可商購金屬源或可製造之。典型上，使用分散於溶劑介質中之金屬粒子，其中該金屬處於其金屬態。銀之鹽類包含，但不限於，硝酸銀、氧化銀、鹵化銀、氰化銀、乙酸銀、碳酸銀、草酸銀、三氟乙酸銀、乙醯丙酮酸銀、苯甲酸銀、檸檬酸銀、乳酸銀、環己烷丁酸銀、四氟硼酸銀、五氟丙酸銀、對甲苯磺酸銀、三氟甲烷磺酸銀。鎳鹽類包含，但不限於，脒化鎳(nickel amidinate)、乙醯丙酮酸鎳、乙酸鎳、碳酸鎳、檸檬酸鎳、環己烷丁酸鎳、酒石酸鎳、氧化鎳、酒石酸鎳、甲酸鎳。銅鹽類包含，但不限於，脒化銅、甲酸銅、氧化銅、環己烷丁酸銅、2-乙基己酸銅、乙醯丙酮酸銅、以及乙酸銅。典型上，金屬奈米粒子係以含量約0.1 wt%至10 wt%包含於該燒穿金屬油墨中，且於另一種具體實施例中其含量為自約05.wt%至5 wt%。 The particle size can range from about 5 [mu]m or less, or for example from about 0.1 [mu]m to 1 [mu]m. Preferably, the particles are nanosized particles. Nano-sized particles have improved performance over larger dimensions because their surface area per unit mass increases compared to larger, larger particles, and they have different physicochemical properties than larger diameter particles. Typically, the metal nanoparticle diameter ranges from about 1000 nm or less, preferably the metal nanoparticle ranges from about 25 nm to 800 nm, and in another embodiment, the self-approximately 100 nm to 400 nm. Metals include, but are not limited to, silver, copper, nickel, gold, palladium, and salts and complexes thereof. Silver, copper, and nickel are typically used. Commercially available metal sources are available or can be manufactured. Typically, metal particles dispersed in a solvent medium are used, wherein the metal is in its metallic state. Silver salts include, but are not limited to, silver nitrate, silver oxide, silver halide, silver cyanide, silver acetate, silver carbonate, silver oxalate, silver trifluoroacetate, silver acetylacetonate, silver benzoate, silver citrate, Silver lactate, silver cyclohexane butyrate, silver tetrafluoroborate, silver pentafluoropropionate, silver p-toluenesulfonate, silver trifluoromethanesulfonate. Nickel salts include, but are not limited to, nickel amidinate, nickel acetate pyruvate, nickel acetate, nickel carbonate, nickel citrate, nickel cyclohexanebutyrate, nickel tartrate, nickel oxide, nickel tartrate, formic acid nickel. Copper salts include, but are not limited to, copper telluride, copper formate, copper oxide, copper cyclohexanebutate, copper 2-ethylhexanoate, copper acetylacetonate, and copper acetate. Typically, the metal nanoparticle is included in the burn through metal ink at a level of from about 0.1 wt% to 10 wt%, and in another embodiment from about 05. wt% to about 5 wt%.

玻料係組成物，其可包含各種氧化物，諸如PbO、SiO₂、 B₂O₃、ZnO、Bi₂O₃、SnO₂及Al₂O₃。商用玻料係典型上維持其專有者但習知上包含一種或多種之該各種氧化物。一般而言，該玻料用之玻璃係於藉由於高溫(例如，高於約1000℃)迴流及同質化該氧化物，且之後研磨及輥輾該玻璃以產生玻料粉末(係提供於商用糊料中者)所形成。該玻料可使用傳統之球磨製程經球磨以得到具有直徑範圍為約1000 nm或更少之粒子，且於另一種具體實施例中自約50 nm至200 nm。或者，玻料可藉由合成技術合成為奈米範圍，該技術如火焰熔射製程者。典型上，玻料之奈米粒子係以含量約0.05 wt%至20 wt%包含於該燒穿金屬油墨中，且於另一種具體實施例中自約0.5 wt%至5.5 wt%。或者，金屬鹽或金屬有機(metal organic，MO)前驅物可用於取代玻料或奈米化玻料。此替代性燒穿劑可為含有Pb、Si、B、Zn、Bi、Sn、或Al、或其混合物或類似材料之金屬鹽或MO前驅物。 A glass frit composition which may comprise various oxides such as PbO, SiO ₂ , B ₂ O ₃ , ZnO, Bi ₂ O ₃ , SnO ₂ and Al ₂ O ₃ . Commercial glass systems typically maintain their proprietary but conventionally include one or more of these various oxides. In general, the glass for the glass is used to reflow and homogenize the oxide due to high temperatures (eg, above about 1000 ° C), and then grind and roll the glass to produce a glass frit (provided for commercial use) Formed in the paste). The glass frit can be ball milled using conventional ball milling processes to yield particles having a diameter ranging from about 1000 nm or less, and in another embodiment from about 50 nm to 200 nm. Alternatively, the glass material can be synthesized into a nanometer range by synthetic techniques, such as a flame spray process. Typically, the glass nanoparticles are included in the burn through metal ink in an amount from about 0.05 wt% to 20 wt%, and in another particular embodiment from about 0.5 wt% to 5.5 wt%. Alternatively, a metal salt or metal organic (MO) precursor can be used to replace the glass or nanoglass. The alternative burnthrough agent can be a metal salt or MO precursor containing Pb, Si, B, Zn, Bi, Sn, or Al, or mixtures thereof or similar materials.

一種或多種金屬源係與於一種或多種溶劑中之一種或多種該燒穿劑混和以形成液體粒子懸浮液，較佳者係奈米粒子，其適合於噴墨印刷或氣溶膠印刷。該燒穿金屬油墨係非糊料或膠體，而為於一種或多種於室溫以及噴墨溫度之溶劑中之物件(較佳者係奈米粒子)之液體或懸浮液。典型於25℃所測得之該等油墨之黏度係在約1至100 cP之範圍，且於另一種具體實施例中於25℃在約5至75 cP之範圍。溶劑包含，但不限於，水、乳酸乙酯、醛類、醇類(如乙醇、甲醇、異丙醇、乙二醇、二乙二醇、丙二醇單甲基 醚、丙二醇單甲基醚乙酸酯、萜品醇、三乙二醇、丙二醇、二丙二醇、己二醇或甘油)、聚醚類(如二甘醇二甲醚、三甘醇二甲醚、四甘醇二甲醚、乙二醇單-及二烷基醚類)或其混合物。溶劑可為該燒穿金屬油墨之餘量被包含於該燒穿金屬油墨中或可加入溶劑以提供約100 wt%。 The one or more metal sources are mixed with one or more of the burnthrough agents in one or more solvents to form a liquid particle suspension, preferably a nanoparticle suitable for ink jet printing or aerosol printing. The burn through metal ink is a non-paste or colloid, and is a liquid or suspension of one or more articles (preferably, nanoparticles) in a solvent at room temperature and ink jet temperature. The viscosity of such inks, typically measured at 25 ° C, is in the range of from about 1 to 100 cP, and in another embodiment is in the range of from about 5 to 75 cP at 25 °C. Solvents include, but are not limited to, water, ethyl lactate, aldehydes, alcohols (eg, ethanol, methanol, isopropanol, ethylene glycol, diethylene glycol, propylene glycol monomethyl) Ether, propylene glycol monomethyl ether acetate, terpineol, triethylene glycol, propylene glycol, dipropylene glycol, hexanediol or glycerol), polyethers (such as diglyme, triethylene glycol dimethyl ether) , tetraglyme, ethylene glycol mono- and dialkyl ethers) or mixtures thereof. The solvent may be included in the burn through metal ink or may be added to the solvent to provide about 100 wt%.

或者，該金屬油墨可包含金屬有機前驅物(MO)及還原劑作為導電金屬源抑或是燒穿劑源。一種或多種如上所述之溶劑可被包含以形成奈米粒子懸浮液。廣泛種類之MO前驅物可用以製造燒穿金屬油墨。該MO前驅物包含金屬離子(M)，其於正於還原劑之還原電位(例如，甲酸鹽約至0.20V)之電位時，或在有還原劑存在下加熱時，還原至其金屬態。金屬之金屬離子包含，但不限於，銀、銅、鉛、鎳、金、鈀及鉑。 Alternatively, the metallic ink may comprise a metal organic precursor (MO) and a reducing agent as a source of conductive metal or a source of burnthrough. One or more solvents as described above may be included to form a nanoparticle suspension. A wide variety of MO precursors can be used to make burn through metal inks. The MO precursor comprises a metal ion (M) which is reduced to its metallic state at a potential which is at a reduction potential of the reducing agent (for example, formate to about 0.20 V) or when heated in the presence of a reducing agent. . Metal ions of metals include, but are not limited to, silver, copper, lead, nickel, gold, palladium, and platinum.

該還原劑可提供電子源以與該MO前驅物反應。於室溫中，該還原劑不與該MO前驅物反應。因此，該MO前驅物可維持可溶，例如，為適合於噴墨印刷之金屬油墨溶液。還原劑包含，但不限於，甲酸鹽類、鹵化物、硝酸鹽類、醇類、醛類、縮醛類、乙二醇、乙二醇二甲酸酯、苯甲醛、乙醛或其混合物。MO前驅物可以含量約0.1 wt%至70 wt%包含在該燒穿金屬油墨中，或例如自約15 wt%至50 wt%。 The reducing agent can provide an electron source to react with the MO precursor. The reducing agent does not react with the MO precursor at room temperature. Thus, the MO precursor can remain soluble, for example, as a metallic ink solution suitable for ink jet printing. The reducing agent includes, but is not limited to, formate salts, halides, nitrates, alcohols, aldehydes, acetals, ethylene glycol, ethylene glycol dicarboxylate, benzaldehyde, acetaldehyde or mixtures thereof. The MO precursor may be included in the burn through metal ink in an amount of from about 0.1 wt% to 70 wt%, or for example, from about 15 wt% to 50 wt%.

除了溶劑外，該燒穿金屬油墨可包含其他添加劑，如黏合劑、分散劑以及界面活性劑以強化該金屬油墨至該抗反射層板之沉積、解析度及接著性。可商購分散劑之實例係DISPERBYK分散劑，如DISPERBYK180、DISPERBYK181、 DISPERBYK182、及DISPERBYK183；BYK分散劑，如BYK301、BYK302、BYK306、及BYK320(皆可得自Byk Chemie,Wallingford,CT)；以及TAMOL^TM分散劑，如TAMOL 681、TAMOL 1124、TAMOL 1254、TAMOL 165A、以及TAMOL 2002分散劑(可得自The Dow Chemical Company,Midland,MI)。分散劑可以自0.01 wt%至高達10 wt%之範圍使用。可商購界面活性劑包含，但不限於，TERGITOL^TM TMN-10界面活性劑、TERGITOL 15-S-9、TERGITOL TMN-6、TERGITOL 15-S-30、PLURONIC 31R1、PLURONIC 103、以及PLURONIC 121。可商購黏合劑包含，但不限於，MORCRYL 350、MORCRYL 430 PLUS、以及LUCIDENE 604。 In addition to the solvent, the burn through metal ink may contain other additives such as binders, dispersants, and surfactants to enhance the deposition, resolution, and adhesion of the metal ink to the antireflective laminate. Examples of commercially available dispersants are DISPERBYK dispersants such as DISPERBYK 180, DISPERBYK181, DISPERBYK 182, and DISPERBY K183; BYK dispersants such as BYK 301, BYK 302, BYK 306, and BYK 320 (all available from Byk Chemie, Wallingford, CT); and TAMOL ^TM dispersants such as TAMOL 681, TAMOL 1124, TAMOL 1254, TAMOL 165A, and TAMOL 2002 dispersant (available from The Dow Chemical Company, Midland, MI). The dispersant can be used in a range from 0.01 wt% to as high as 10 wt%. Commercially available surfactant include, but are not limited to, TERGITOL ^TM TMN-10 surfactant, TERGITOL 15-S-9, TERGITOL TMN-6, TERGITOL 15-S-30, PLURONIC 31R1, PLURONIC 103, and PLURONIC 121. Commercially available adhesives include, but are not limited to, MORCRYL 350, MORCRYL 430 PLUS, and LUCIDENE 604.

燒穿可於溫度至少約400℃完成，且於另一種具體實施例中，約400℃至1000℃，且於另一種具體實施例中自約650℃至1000℃。該燒穿製程可於傳統之烘箱或紅外線(IR)帶狀爐中完成。該燒穿製程減少或全部消除傳統之成像、光微影、雷射寫入或蝕刻方法之需求(該等方法於金屬化前選擇性移除抗反射層板的某些部分)。該步驟之減少或消去係藉由減少製程時間以及先前使用於傳統製程材料之製造成本，而改良製造方法之效率。 Burn through can be accomplished at a temperature of at least about 400 ° C, and in another embodiment, from about 400 ° C to 1000 ° C, and in another embodiment from about 650 ° C to 1000 ° C. The burn through process can be accomplished in a conventional oven or infrared (IR) belt furnace. The burn-through process reduces or completely eliminates the need for conventional imaging, photolithography, laser writing or etching methods (these methods selectively remove portions of the anti-reflective laminate prior to metallization). The reduction or elimination of this step improves the efficiency of the manufacturing process by reducing process time and manufacturing costs previously used for conventional process materials.

利用該燒穿方法沉積之該金屬種晶層係於自約0.1至12微米，或例如自約0.25至2.5微米之範圍。之後，該種晶層係藉由光誘導鍍覆(light induced plating,LIP)建立至少一層額外之金屬層。額外之金屬層可包含，但不限於，如銀、銅、鎳、金、鈀或鉑之金屬。該額外之金屬 可為銀、銅或鎳或其類似物。光誘導鍍覆之完成係直至經鍍覆層之金屬厚度達到至少約1微米，或如約5至20微米，或如約10至15微米。 The metal seed layer deposited by the burn through method is from about 0.1 to 12 microns, or such as from about 0.25 to 2.5 microns. Thereafter, the seed layer is formed by at least one additional metal layer by light induced plating (LIP). Additional metal layers may include, but are not limited to, metals such as silver, copper, nickel, gold, palladium or platinum. The extra metal It may be silver, copper or nickel or the like. The photoinduced plating is completed until the metal thickness of the plated layer reaches at least about 1 micron, or such as about 5 to 20 microns, or such as about 10 to 15 microns.

無電和電解金屬鍍覆浴皆可用以沉積額外之金屬層。可使用無電和電解金屬鍍覆浴。若該金屬係銀，可使用無氰化物銀電鍍浴。若該金屬源係無電浴，鍍覆可於無外加電流使用下完成。若該金屬源係來自電解鍍覆浴，將施加後側電位(整流器)至該半導體晶圓基板。電流密度範圍可自約0.1 A/dm²至10 A/dm²，且於另一種具體實施例中，自約0.5 A/dm²至2 A/dm²。該電流要求係取決於該使用之半導體晶圓尺寸。該光線可為連續或脈衝形態。該半導體係沉浸於該金屬鍍覆浴中且施加光線至該半導體。可用於鍍覆製程之光線包含，但不限於，可見光、IR、紫外光(UV)及X-射線。光源包含，但不限於，白熾燈、發光二極體(LED)光源、IR燈、螢光燈、鹵素燈及雷射。 Both electroless and electrolytic metal plating baths can be used to deposit additional metal layers. Electroless and electrolytic metal plating baths can be used. If the metal is silver, a cyanide-free silver plating bath can be used. If the metal source is without an electric bath, the plating can be completed without using an external current. If the metal source is from an electrolytic plating bath, a backside potential (rectifier) is applied to the semiconductor wafer substrate. The current density can range from about 0.1 A/dm ² to 10 A/dm ² , and in another specific embodiment, from about 0.5 A/dm ² to 2 A/dm ² . This current requirement is dependent on the semiconductor wafer size used. The light can be in a continuous or pulsed form. The semiconductor is immersed in the metal plating bath and applies light to the semiconductor. Light that can be used in the plating process includes, but is not limited to, visible light, IR, ultraviolet light (UV), and X-rays. Light sources include, but are not limited to, incandescent lamps, light emitting diode (LED) sources, IR lamps, fluorescent lamps, halogen lamps, and lasers.

該鍍覆池係以對於該金屬鍍覆浴為化學惰性且典型上具有最小光穿透率約40至60%之材料製作。或者，該晶圓可垂直移位於鍍覆池中且從上方照光，於此例中該鍍覆池不須具有該至少最小光穿透率。 The plating bath is made of a material that is chemically inert to the metal plating bath and typically has a minimum light transmission of about 40 to 60%. Alternatively, the wafer can be moved vertically in the plating bath and illuminated from above, in which case the plating bath need not have the at least minimum light transmission.

藉由用光能照射該半導體晶圓之前側或射極層，於該半導體晶圓之射極層發生鍍覆。該撞擊光能於該半導體晶圓中產生電流。該於前側之鍍覆率係主要藉由自電流源(典型上係整流器)施予之電流而為可控制。調整光密度、浴溫度、還原劑活性、起始晶圓條件、摻雜程度以及其他參數 亦可影響鍍覆率。 Plating is performed on the emitter layer of the semiconductor wafer by irradiating the front side or the emitter layer of the semiconductor wafer with light energy. The impinging light can generate a current in the semiconductor wafer. The plating rate on the front side is controllable mainly by the current applied from a current source (typically a rectifier). Adjust optical density, bath temperature, reducing agent activity, starting wafer conditions, doping levels, and other parameters It can also affect the plating rate.

依該方法製造之該金屬接觸增加了半導體裝置之效率，因而較許多具有可相比擬之尺寸和單位面積之傳統半導體裝置提供增加之輸出功率。依據該燒穿及光誘導鍍覆方法製造之半導體之參數(如開路電流(I_SC)，填充係數(FF)和全電池效率)係較許多傳統製造半導體裝置之製程者高。FF係決定整體半導體裝置行為之要項。較高FF產生較大效率。該用燒穿及LIP方法之半導體裝置之FF較許多具有可相比擬之尺寸和單位面積之傳統之半導體裝置具有較高FF。典型上，該等參數於工業上使用稱為太陽模擬器之裝置予以測量。該等太陽模擬器之實例係QuickSun® 120CA,540LA及700A電池太陽模擬器，得自Endeas Oy,Espoo,Finland。該等裝置係用於結晶及薄膜光伏產品兩者之定性。 The metal contact fabricated in this manner increases the efficiency of the semiconductor device and thus provides increased output power over many conventional semiconductor devices having comparable sizes and unit sizes. The parameters of the semiconductor fabricated according to the burn-through and photo-induced plating methods (such as open circuit current ( _ICC ), fill factor (FF) and full cell efficiency) are higher than those of many conventional semiconductor device manufacturers. The FF system determines the essentials of the overall semiconductor device behavior. Higher FF produces greater efficiency. The FF of the semiconductor device using the burn-through and LIP method has a higher FF than many conventional semiconductor devices having comparable sizes and unit sizes. Typically, these parameters are measured industrially using a device called a solar simulator. Examples of such solar simulators are the QuickSun® 120CA, 540LA and 700A battery solar simulators available from Endeas Oy, Espoo, Finland. These devices are used for the characterization of both crystalline and thin film photovoltaic products.

該方法亦使減少遮蔽及改良入射光吸收度之精細線電流軌道得以形成。該燒穿及光誘導鍍覆製程藉由消去替代性方法中之諸如光微影及雷射寫入等步驟，而減少了該半導體物件製造之步驟數量，且減少材料之破損，因而減少整體製造半導體裝置之花費。除此之外，相比於許多傳統之半導體裝置，該燒穿及光誘導鍍覆製程提供改良之該金屬層及該半導體表面間之歐姆接觸。此外，該方法導致較少金屬施加至該電池，因而導致較低材料成本。其係為人所欲，特別是於使用貴金屬於種晶層或建立金屬層時。除此之外，於一生產線上，印刷燒穿油墨與光誘導鍍覆之方 法可提供每秒一晶圓或較佳之產能。 This method also enables the formation of fine line current trajectories that reduce shadowing and improve the absorbance of incident light. The burn-through and light-induced plating process reduces the number of steps in the fabrication of the semiconductor article and reduces the damage of the material by eliminating steps such as photolithography and laser writing in an alternative method, thereby reducing overall manufacturing. The cost of semiconductor devices. In addition, the burn-through and photo-induced plating processes provide improved ohmic contact between the metal layer and the surface of the semiconductor compared to many conventional semiconductor devices. Moreover, this method results in less metal being applied to the battery, thus resulting in lower material costs. It is desirable, especially when using precious metals in seed layers or in establishing metal layers. In addition, on the production line, the printing burn-through ink and the light-induced plating side The method can provide one wafer per second or better capacity.

因例示說明之目的而引入下列實施例，但不意圖限制本發明之範疇。 The following examples are introduced for the purpose of illustration, but are not intended to limit the scope of the invention.

實施例1 Example 1

燒穿金屬油墨如下製備：混合20 wt%粉末之銀金屬奈米粒子(由B.Y.Ahn,E.B.Duoss,M.J.Motala,X.Guo,S.-I.Park,Y.Xiong,J.Yoon,J.Yoon,R.G.Nuzzo,J.A.Rogers,and J.A.Lewis，「Omnidirectional Printing of Flexible,Spanning,and Dtretchable Silver Microelectrodes」，Science,323,1590-93(2009)揭露之方法所製備)，含有玻料之可商購專有PbO糊料之5 wt%奈米粒子，及足夠使該金屬油墨組成物達100 wt%之含量之乙二醇溶劑；且形成均勻奈米粒子懸浮液。該銀奈米粒子具有平均直徑範圍250至350 nm且該PbO玻料糊之奈米粒子具有平均直徑範圍50至150 nm。該PbO玻料糊係與60 wt%乙二醇及40 wt%水之混合物混摻以形成均勻懸浮液。之後，於可商購TAMOL^TM681分散劑存在下，該懸浮液係用1至0.1至5 mm之氣化鋯球球磨24小時以提供奈米化粒子。 The burn through metal ink was prepared by mixing 20 wt% powder of silver metal nanoparticles (by BYAhn, EB Duoss, MJ Motala, X. Guo, S.-I. Park, Y. Xiong, J. Yoon, J. Yoon, RGNuzzo). , JA Rogers, and JA Lewis, "Omnidirectional Printing of Flexible, Spanning, and Dtretchable Silver Microelectrodes", Science, 323, 1590-93 (2009)), commercially available proprietary PbO paste containing glass 5 wt% of nanoparticle, and an ethylene glycol solvent sufficient to make the metallic ink composition up to 100 wt%; and form a uniform nanoparticle suspension. The silver nanoparticles have an average diameter ranging from 250 to 350 nm and the PbO glass paste nanoparticles have an average diameter ranging from 50 to 150 nm. The PbO glass paste was blended with a mixture of 60 wt% ethylene glycol and 40 wt% water to form a homogeneous suspension. Thereafter, in the presence of a commercially available TAMOL ^TM 681 dispersant, the suspension of zirconium-based balls vaporization from 1 to 0.1 to 5 mm ball milled for 24 hours to provide the nano-particles.

提供六十個經摻雜且其前側具有錐狀伸高及表面積為243 cm²之單晶及多晶矽晶圓(可自Wafernet,San Jose,CA商購而得)。每一個經摻雜之矽晶圓於該晶圓前側上具有n+摻雜區形成射極層。每一個晶圓於該射極層板之下具有pn接面。該每一個晶圓之前側係塗覆有由Si₃N₄組成之鈍化 或抗反射層。該每一個晶圓之背側係p+摻雜且經絲網印刷塗覆可商購鋁太陽能糊料(可自Electroscience Laboratories,King of Prussia,PA商購而得)。 Sixty-six single crystal and polycrystalline germanium wafers (commercially available from Wafernet, San Jose, CA) having doped sides and having a tapered extension and a surface area of 243 cm ² were provided. Each doped germanium wafer has an n+ doped region on the front side of the wafer to form an emitter layer. Each wafer has a pn junction below the emitter layer. The front side of each wafer is coated with a passivation or anti-reflection layer composed of Si ₃ N ₄ . The back side of each wafer was p+ doped and screen printed with commercially available aluminum solar paste (commercially available from Electroscience Laboratories, King of Prussia, PA).

該銀油墨係置於DirectMask^TM DoD 65噴墨印刷裝置(可自SCMID GmbH and Co.,Freudenstadt,Germany商購而得)之儲庫。二十個經摻雜單晶晶圓係以一次一片的方式置於該噴墨裝置之施加(或稱塗覆)板上，且該銀油墨係選擇性沉積於Si₃N₄抗反射層板上以形成複數條平行電流軌道。該噴墨噴嘴通過每一個沉積處五次以形成電流軌道。該印刷頭溫度係35℃，且該材料沉積寬度係80微米。該印刷頭滴料頻率係5 kHz。該平台(階)係加熱至70℃。該印刷圖案含有2匯流排(2mm寬)及69條電流線。該印刷電流線之線寬係80微米。於種晶層施用後，每一個晶圓係風乾且之後於IR帶狀爐(可自Sierra Therm,Watsonville,CA商購而得)燒製。該晶圓係加熱至850℃經5秒以趕掉銀油墨中之溶劑，且讓該銀金屬油墨燒穿該Si₃N₄抗反射塗層及與下方之半導體晶圓之射極層形成歐姆接觸。之後，該晶圓係自烘箱移出且使之冷卻至室溫。 The silver-based ink placed DirectMask ^TM DoD 65 inkjet printer (available from SCMID GmbH and Co., Freudenstadt, Germany commercially obtained) of the reservoir. Twenty doped single crystal wafers are placed on the application (or coating) plate of the inkjet device one at a time, and the silver ink is selectively deposited on the Si ₃ N ₄ anti-reflection laminate Upper to form a plurality of parallel current tracks. The inkjet nozzle passes through each deposition five times to form a current track. The print head temperature was 35 ° C and the material deposition width was 80 microns. The print head drool frequency is 5 kHz. The platform (stage) is heated to 70 °C. The printed pattern contains 2 bus bars (2 mm wide) and 69 current lines. The line of the printed current line is 80 microns wide. After application of the seed layer, each wafer was air dried and then fired in an IR ribbon furnace (commercially available from Sierra Therm, Watsonville, Calif.). The wafer is heated to 850 ° C for 5 seconds to remove the solvent in the silver ink, and the silver metal ink is burned through the Si ₃ N ₄ anti-reflective coating and forms an ohmic with the emitter layer of the underlying semiconductor wafer. contact. Thereafter, the wafer was removed from the oven and allowed to cool to room temperature.

之後，每一個晶圓係經Amray 1830掃描式電子顯微鏡(SEM)檢驗(可自Amray Inc.,Bedford,MA商購而得)，以對每一個電流軌道銀種晶層之高度及寬度予以測量。測量到之平均高度係0.5微米且測量到之平均寬度係80微米。 Each wafer was then inspected by Amray 1830 scanning electron microscopy (SEM) (commercially available from Amray Inc., Bedford, MA) to measure the height and width of each current orbital silver seed layer. . The average height measured was 0.5 microns and the average width measured was 80 microns.

將該噴墨印刷電流軌道方法重復於剩餘晶圓上。二十個晶圓接受十程之銀油墨，而二十個晶圓接受二十程之銀 油墨，以於每一個晶圓上形成69條電流軌道。該經歷10程材料之晶圓平均有1微米厚度及平均寬度80微米。該經歷20程材料之晶圓平均有2微米厚度及平均寬度80微米。將該晶圓加熱至850℃經5秒以改掉銀油墨中之溶劑，且讓該銀金屬油墨燒穿該Si₃N₄抗反射塗層及與下方之半導體晶圓之射極層形成歐姆接觸。將該晶圓置於對流烘箱中並於800℃至825℃加熱10分鐘以趕掉銀油墨中之溶劑，且讓該銀金屬油墨燒穿該Si₃N₄抗反射塗層及與下方之半導體晶圓之射極層形成歐姆接觸。之後，該晶圓自烘箱移出且使之冷卻至室溫。 The inkjet printing current track method is repeated on the remaining wafers. Twenty wafers received ten silver inks, while twenty wafers received twenty silver inks to form 69 current tracks on each wafer. The wafers subjected to the 10-pass material have an average thickness of 1 micron and an average width of 80 micrometers. The wafers of the 20-pass material have an average thickness of 2 microns and an average width of 80 microns. The wafer is heated to 850 ° C for 5 seconds to remove the solvent in the silver ink, and the silver metal ink is burned through the Si ₃ N ₄ anti-reflective coating and forms an ohmic with the emitter layer of the underlying semiconductor wafer. contact. The wafer is placed in a convection oven and heated at 800 ° C to 825 ° C for 10 minutes to remove the solvent in the silver ink, and the silver metal ink is burned through the Si ₃ N ₄ anti-reflective coating and the semiconductor underneath The emitter layer of the wafer forms an ohmic contact. Thereafter, the wafer was removed from the oven and allowed to cool to room temperature.

每一個晶圓係之後經相同的SEM檢驗，以對每一個電流軌道之高度及寬度予以測量。經10程油墨之晶圓之經測量平均高度係1微米且經測量平均寬度係80微米。該經20程油墨之晶圓之經測量平均高度係2微米且經測量平均寬度係80微米。 Each wafer system is then subjected to the same SEM inspection to measure the height and width of each current track. The measured average height of the wafer of 10 passes of ink was 1 micron and the measured average width was 80 microns. The 20-pass ink wafer has a measured average height of 2 microns and a measured average width of 80 microns.

之後，該晶圓之半數電流軌道係藉由使用如下表所揭露之水性無氰化物銀金屬電鍍浴之光誘導鍍覆，鍍覆10微米銀金屬層。 Thereafter, the half current track of the wafer was plated with a 10 micron silver metal layer by photoinduced plating using an aqueous cyanide free silver metal plating bath as disclosed in the following table.

足夠體積之銀電鍍浴係置於複數個鍍覆池中以填滿池。該浴之pH值範圍自9.5至10.5。該浴溫度係於鍍覆期間維持在25℃至35℃。該鍍覆池裝設有250瓦燈泡和銀陽極。將一半之該晶圓沉浸於裝有該浴之鍍覆池中。以傳統整流器提供電流源。該浴、晶圓、銀陽極以及整流器係彼此電性連接。伴隨燈泡照射，施予1至5 A/dm²之電流密度。鍍覆15分鐘以沉積10微米電鍍銀層於銀種晶層上。 A silver plating bath of sufficient volume is placed in a plurality of plating baths to fill the pool. The pH of the bath ranges from 9.5 to 10.5. The bath temperature is maintained between 25 ° C and 35 ° C during plating. The plating cell is equipped with a 250 watt bulb and a silver anode. Half of the wafer was immersed in a plating bath containing the bath. A current source is provided by a conventional rectifier. The bath, wafer, silver anode, and rectifier are electrically connected to each other. The current density of 1 to 5 A/dm ^{2 was} applied with the bulb irradiation. Plated for 15 minutes to deposit a 10 micron electroplated silver layer onto the silver seed layer.

之後，該電鍍之銀係用IPC-TM-650 2.4.1膠帶測試法評估接著性。將一條1.27 cm寬之3M 600品牌膠帶(可自3M Company,St.Paul,MN商購而得)貼至樣品上。於移除任何包埋之空氣且接著少於一分鐘後，將該膠帶輕快地以90度角自該晶圓表面移除。於膠帶測試後觀察到無銀自該晶圓上移除。 Thereafter, the electroplated silver was evaluated for adhesion using the IPC-TM-650 2.4.1 tape test method. A 1.27 cm wide 3M 600 brand tape (commercially available from 3M Company, St. Paul, MN) was applied to the sample. After removing any embedded air and then less than one minute, the tape was lightly removed from the wafer surface at a 90 degree angle. No silver was observed to be removed from the wafer after the tape test.

實施例2 Example 2

之後，該每一個晶圓之I_SC係利用可商購之QuickSun® 120CA電池太陽模擬器搭配照度減退電池分析法(irradiance decay cell analysis method，IDCAM)測量。具有種晶層厚度0.5微米、1微米、及2微米之樣品於850℃燒製5秒。該每一個晶圓之I_SC係以安培為單位測量。之後藉由於實施例1所述浴中以電流密度1.5 ASD光誘導鍍覆而電鍍樣品。圖示比較平均值，如第1圖所示者。經燒製及光誘導鍍覆加以鍍覆兩者之晶圓具有最高的平均I_SC值。具有1或2微米種晶層之晶圓顯示出最高平均I_SC值約8安培。於該種晶層上加上光誘導鍍覆銀層係改善了光產生電流。 Thereafter, the I _SC of each wafer was measured using a commercially available QuickSun® 120CA battery solar simulator with an irradiance decay cell analysis method (IDCAM). A sample having a seed layer thickness of 0.5 μm, 1 μm, and 2 μm was fired at 850 ° C for 5 seconds. The I _SC of each wafer is measured in amps. The sample was then plated by photoinduced plating at a current density of 1.5 ASD in the bath described in Example 1. The graph compares the average values as shown in Figure 1. Wafers that are both fired and photoinduced plated have the highest average I _SC value. Wafers with 1 or 2 micron seed layers showed a maximum average I _SC value of about 8 amps. Adding a light-induced silver plating layer to the seed layer improves the light generating current.

實施例3 Example 3

於實施例2中討論的每一個晶圓之池室效率(cell efficiency，CE)係由QuickSun® 120CA電池太陽模擬器搭配照度減退電池分析法(IDCAM)測量。每一個晶圓之CE係以百分比測量。圖示比較平均值，如第2圖所示者。經燒製及光誘導鍍覆加以鍍覆兩者之晶圓具有最高的平均百分效率值。具有1或2微米種晶層之晶圓顯示出最高平均百分效率值約12%。於該種晶層上加上光誘導鍍覆銀層係改善了半導體效率。 The cell efficiency (CE) for each wafer discussed in Example 2 was measured by the QuickSun® 120CA Battery Solar Simulator with Illumination Reduction Battery Analysis (IDCAM). The CE of each wafer is measured as a percentage. The graph compares the averages as shown in Figure 2. Wafers that have been fired and photoinducedly plated have the highest average percent efficiency values. Wafers with 1 or 2 micron seed layers showed a maximum average percent efficiency value of about 12%. Adding a light-induced silver plating layer to the seed layer improves semiconductor efficiency.

實施例4 Example 4

將該實施例1之油墨填裝入Optomec品牌單噴嘴R&D等級氣溶膠印刷機(可自Optomec,St.Paul,MN商購而得)之儲庫中。使用該印刷機，以與實施例1之相同條件印刷 具有69條電流線和二匯流排之圖案於5個太陽能電池晶圓之表面。該印刷機通過每一個晶圓五十次以沉積該圖案。於印刷後該印刷線寬平均有寬度50微米及高度10微米。該晶圓係經與實施例1之相同條件燒製，且該電池亦與實施例1之相同銀鍍覆浴於相同條件下經LIP印鍍覆。 The ink of Example 1 was filled into a reservoir of an Optomec brand single nozzle R&D grade aerosol printer (commercially available from Optomec, St. Paul, MN). Printing using the same conditions as in Example 1 using the printing machine There are 69 current lines and two bus bars on the surface of 5 solar cell wafers. The printer passes the wafer fifty times per wafer to deposit the pattern. The printed line width has an average width of 50 microns and a height of 10 microns after printing. The wafer was fired under the same conditions as in Example 1, and the battery was also plated with LIP printing under the same conditions as the silver plating bath of Example 1.

此外，含有商用糊料之樣品A、B以及C係絲網印刷於與實施例1相同種類之晶圓上，以形成80微米寬之69條電流線及2 mm寬之2個匯流排。這些商用糊料係工業上典型者，含有大型3至5微米銀片粒子與含有PbO之玻料。該糊料樣品之平均線寬係於80至100微米及8至10微米厚。之後，電池係使用與實施例1之電池相同條件燒製及電鍍。於鍍覆之後，以晶圓切割機小心地切下這些電池之2.3 cm寬條帶。使用晶圓切割機，自具有藉由氣溶膠印刷機沉積之種晶層之電池上切下相似的2.3 cm寬之條帶。這些自每一例中之每一電池切下之2.3 cm寬條帶以平行於匯流排之方向切割，且由一系列電性絕緣之2.3 cm長平行線組成。自該一系列之線，該接觸電阻可經傳輸線路法予以測量。使用四點探針測量搭配源測量器(可自Keithley Series A 2600A SourceMeter,Cleveland,OH商購而得)與該傳輸線路法，計算該每一個樣品之接觸電阻，且繪製於第3圖。經氣溶膠印刷之電池顯示出全樣品中最低之平均接觸電阻。具有光誘導鍍覆銀之經氣溶膠印刷之電池相較於具有光誘導鍍覆銀之經絲網印刷之電池具有改良之接觸電阻。經氣溶膠印刷之種晶層樣品之平均接觸電阻係3 毫歐姆-平方公分。該方盒代表數據之數值範圍，且該方盒之中心線代表平均值。較低之接觸電阻顯示該電池之整體電阻有所減少，以致使有較高效率。 Further, samples A, B, and C containing a commercial paste were screen-printed on the same type of wafer as in Example 1 to form 69 current lines of 80 μm width and 2 bus bars of 2 mm width. These commercial pastes are typical in the industry and contain large 3 to 5 micron silver flakes and glass containing PbO. The average line width of the paste sample was between 80 and 100 microns and 8 to 10 microns thick. Thereafter, the battery was fired and plated under the same conditions as those of the battery of Example 1. After plating, the 2.3 cm wide strips of these cells were carefully cut with a wafer cutter. A similar 2.3 cm wide strip was cut from a cell having a seed layer deposited by an aerosol printer using a wafer dicing machine. These 2.3 cm wide strips cut from each of the cells in each case were cut parallel to the direction of the busbars and consisted of a series of electrically insulated 2.3 cm long parallel lines. From this series of lines, the contact resistance can be measured by the transmission line method. The contact resistance of each of the samples was calculated using a four-point probe measurement collocation source measureer (commercially available from Keithley Series A 2600A SourceMeter, Cleveland, OH) and plotted in Figure 3. The aerosol printed battery showed the lowest average contact resistance in the full sample. Aerosol-printed cells with light-induced silver plating have improved contact resistance compared to screen-printed cells with light-induced silver plating. Average contact resistance of aerosol-coated seed layer samples 3 Milliohm-square centimeters. The box represents the range of values for the data, and the centerline of the box represents the average. The lower contact resistance indicates that the overall resistance of the battery is reduced to result in higher efficiency.

第1圖說明具有以燒製玻料銀油墨製備之銀金屬接觸之結晶矽半導體晶圓之短路電流對比具有以燒製玻料銀油墨製備之銀金屬接觸及依據實施例之額外光誘導鍍覆銀層之半導體晶圓之短路電流；第2圖說明具有以燒製玻料銀油墨製備之銀金屬接觸之結晶矽半導體晶圓之效率對比具有以燒製玻料銀油墨製備之銀金屬接觸及依據實施例之額外光誘導鍍覆銀層之半導體晶圓之效率；以及第3圖說明燒穿後接著光誘導鍍覆銀所製造之金屬接觸對比依據一個實施例之使用燒穿糊料但未進行光誘導鍍覆之接觸之電流線之接觸電阻(單位為毫歐姆-平方公分(mOhm-cm²))。 Figure 1 illustrates the short circuit current of a crystalline germanium semiconductor wafer having a silver metal contact prepared by firing a glassy silver ink versus silver metal contact prepared with a fired glass silver ink and additional light induced plating according to an embodiment. Short-circuit current of a semiconductor wafer of a silver layer; FIG. 2 illustrates the efficiency of a crystalline germanium semiconductor wafer having a silver metal contact prepared by firing a glassy silver ink versus silver metal contact prepared by firing a glass silver ink and The efficiency of the additional light-induced silver-plated semiconductor wafer according to the embodiment; and Figure 3 illustrates the metal contact of the light-induced silver plating after burn-through followed by the burn-through paste according to one embodiment but not The contact resistance of the current line contacting the light-induced plating (in milliohm-square centimeters (mOhm-cm ² )).

由於本案的圖為結果數據，並非本案的代表圖。故本案無指定代表圖。 Since the picture in this case is the result data, it is not the representative figure of this case. Therefore, there is no designated representative map in this case.

Claims (10)

一種方法包括：a)提供燒穿金屬油墨；b)選擇性施加該燒穿金屬油墨至半導體基板上之抗反射塗層；c)燒製該具有抗反射塗層之半導體基板及該燒穿金屬油墨以提供來自該燒穿金屬油墨之金屬及該半導體基板間之歐姆接觸；以及d)藉由光誘導鍍覆，於該來自燒穿金屬油墨之金屬上沉積一層或多層金屬層。 A method comprising: a) providing a burn through metal ink; b) selectively applying the burn-through metal ink to an anti-reflective coating on the semiconductor substrate; c) firing the semiconductor substrate having the anti-reflective coating and the burn-through metal An ink to provide an ohmic contact between the metal from the burn through metal ink and the semiconductor substrate; and d) depositing one or more metal layers on the metal from the burn through metal ink by photoinduced plating. 如申請專利範圍第1項所述之方法，其中，該燒穿金屬油墨包括呈金屬粉末、金屬鹽類、金屬有機化合物、金屬錯合物或其混合物形態之金屬。 The method of claim 1, wherein the burn through metal ink comprises a metal in the form of a metal powder, a metal salt, a metal organic compound, a metal complex or a mixture thereof. 如申請專利範圍第2項所述之方法，其中，該金屬係具有直徑約1000 nm或更少之粒子。 The method of claim 2, wherein the metal has particles having a diameter of about 1000 nm or less. 如申請專利範圍第2項所述之方法，其中，該金屬係選自銀、金、鈀、鉑、銅、錫、鎳、鈷、鐵以及鉛。 The method of claim 2, wherein the metal is selected from the group consisting of silver, gold, palladium, platinum, copper, tin, nickel, cobalt, iron, and lead. 如申請專利範圍第1項所述之方法，其中，該燒穿金屬油墨包括下述之一者或多者：玻料、金屬鹽類、金屬錯合物以及金屬有機化合物。 The method of claim 1, wherein the burn through metal ink comprises one or more of the following: glass, metal salts, metal complexes, and metal organic compounds. 如申請專利範圍第5項所述之方法，其中，該玻料係具有直徑約1000 nm或更少之粒子。 The method of claim 5, wherein the glass frit has particles having a diameter of about 1000 nm or less. 如申請專利範圍第1項所述之方法，其中，加熱係於溫度至少約400℃完成。 The method of claim 1, wherein the heating is performed at a temperature of at least about 400 °C. 如申請專利範圍第1項所述之方法，其中，該藉由光誘導鍍覆而沉積之金屬層係選自銀、金、鈀、鉑、銅、錫、鎳、鈷、鐵以及鉛。 The method of claim 1, wherein the metal layer deposited by photoinduction plating is selected from the group consisting of silver, gold, palladium, platinum, copper, tin, nickel, cobalt, iron, and lead. 如申請專利範圍第1項所述之方法，其中，該藉由光誘導鍍覆而沉積之金屬層係約5微米至20微米厚。 The method of claim 1, wherein the metal layer deposited by photoinduction plating is about 5 microns to 20 microns thick. 如申請專利範圍第1項所述之方法，其中，該燒穿金屬油墨係藉由噴墨或氣溶膠施加。 The method of claim 1, wherein the burn through metal ink is applied by inkjet or aerosol.