1253121 九、發明說明： 【發明所屬之技術領域】 、、本發明是有關於-種提高紅外線感測器生產良率的方 ^別疋有關於-種增加懸浮薄膜接腳和基材的連接點 強度’以增加紅外線感測器生產良率的方法。 【先前技術】 ，隨著半導體工業與電子技術的快速進步，紅外線感測器 的製造技術也日益進步。紅外線感測器不僅僅可以利用在醫 學上’進行體溫的量測’更可湘於科學、商業及軍事上， 如雷射偵測、飛彈導向、紅外線光譜儀、遙控器、防盜器、 熱像谓察等用途上。而紅外線感測器主要可分為熱型 (thermal)及里子型（ph〇t〇n):大類。由於熱型紅外線感測器 在使用上較為方便，一般的應用也較為廣泛。 、 鈸而θ，熱型紅外線感測器包括熱電偶（thermocouple) 感測為、焦電（pyroelectnc)感測器、與熱阻型的紅外線感測 器（m1Crobolometer )。熱電偶型的紅外線感測器即熱電堆 (thermopile) ’其結構為一系列串連的熱電偶，熱接點 junction)排列在懸浮薄膜上，冷接點（c〇M juncti〇n)則棑列在 基材上，懸浮薄膜與基材之間的接腳必需通過一系列的熱電 偶線，故接腳很寬，通常接腳亦很短。 熱阻型的紅外線感測器，係利用一片具有高電阻溫度係 數（Temperature Coefficient of Resistance; TCR)的熱感測薄 膜，將其製作在感測器的懸浮薄膜上，由至少二支接腳將懸 1253121 浮薄膜支撐在基材上方 傳導到美材上。…、感測薄膜的電性亦由此二支接腳 電型的L卜^ 基材·^電路進行信_取與處理。焦 的旱是使用—片焦電薄膜材料，製作在感 ==。熱阻型與焦電型感測材料的懸浮薄膜， _基材的接腳之要求都-樣，基本上，在力學社 賴強的前題下，為了減少熱導（thermai_duetance):; 要求接腳越少、越長、越窄、越薄越好。 ί懸浮薄膜和接腳因為製程的緣故’通常會有剩餘 應力’适些應力會壓迫結構，尤其是結構的接合點。接合點 由於使用不同的製程和材料，力學強度會比較弱，若應力大 過於接合的強度’接合點即可能破裂。同時，欲進行接腳和 基材的接σ %，接腳的高度必須從懸浮薄膜的高度降到讀取 電路之導電層的表面，但是接腳上的導電薄膜很薄，因此形 成比較脆弱的電性連接。 【發明内容】 鑒於上述之先前技術說明中，傳統的紅外線感測器由於 接腳與讀取電路之導電層接合處的高度落差甚大，且相對於 接腳的覓度與厚度，接腳的長度又十分的長，使得接腳和基 材的連接之強度非常脆弱，進而影響到紅外線感測器的生產 良率。 因此，本發明的目的之一係提供一種增加懸浮薄膜接腳 和基材的連接之強度的方法，使提升紅外線感測薄膜的接腳 與基材中的讀取電路之結合強度。 1253121 本發明的另一目的是在提供一種增加懸浮薄膜接腳和 基材的連接點之強度的方法，使增加紅外線感測器的生產良 率。 根據上述之目的，本發明係提出一種增加懸浮薄膜接腳 和基材的連接點之強度的方法，此方法包含下列步驟，首先 一讀取電路晶片被提供，接著在讀取電路晶片之上形成一犧 牲層，然後於此犧牲層之中形成一電性接觸窗並露出讀取電 路晶片之一導電層。接著將一金屬層填入於電性接觸窗，並 形成一導電薄膜與金屬層電性耦合。 然後’依序形成一紅外線感測層與一上層介電層於導電 薄膜之上。當進行圖案化紅外線感測層，保留電性接觸窗上 方之紅外線感測層。同時，更可以在圖案化上層介電層時， 保留電性接觸窗上方紅外線感測層之上的上層介電層，以保 護接觸窗上方紅外線感測層。 其中，在形成上述之導電薄膜與紅外線感測層之前，更 可先形成一底層介電層。利用穿過上層介電層與下層介電層 之蝕刻窗，蝕刻犧牲層，使懸浮薄膜騰空。而上述之犧牲 ^的材料係為聚亞㈣’金屬層$可以利用減極電鑛錄等 製程，以填入金屬層於電性接觸窗之中。 、本發明之增加懸浮薄膜接腳和基材的連接之強度的方 法使熱型紅外線感測器的懸浮薄膜接腳和基材的連接點之 強度口而提升，更使接腳和基材的連接點的電性連接更能得 到保€且同g夺利用保留電性接觸窗上方之紅外線感測層與 上層’I電層’更可進一步增加接腳和基材的連接點之強度。 1253121 使熱型紅外線感測器，特別是熱阻型的紅外線感測器，不僅 生產良率為之提升，更有效提高其電性品質。 【實施方式】 本發明之增加懸浮薄膜接腳和基材的連接點之強度的 方法’有效提南紅外線感測薄膜接腳與基材中讀取電路之電 性結合強度，與增加接腳和基材的連接點之機械強度，可以 提高紅外線感測器生產時的良率。以下將以圖示及詳細說明 清楚說明本發明之精神，如熟悉此技術之人貢在瞭解本發明 之車乂佳實&例後’當可由本發明所教示之技術，加以改變及 修飾，其並不脫離本發明之精神與範圍。 第1 10圖係為本發明之增加懸浮薄膜接腳強度的方 法：不思圖’係以一熱型紅外線焦面陣列元件的讀取電 路曰a片為例來5兒明本發明之增加懸浮薄膜接腳強度的方 多閱第1圖熱型紅外線焦面陣列元件的讀取電路晶片 上先形成導電| 10,例如是銘、銘銅、或㈣銅合金等， 以及保護讀取電路的介電層i i。 接著參閱第2圖，製作一犧牲層2卜例如是聚亞醯胺 (P咖nude)，此犧牲層21在導電層1〇之上具有一開孔22。 二閱弟3圖讀取電路的介電層u，使開孔22到達導 電層10,此開孔22即形成紅外線感測薄膜接腳到基材中讀 ::路的電性接觸窗36。參閱第4_，填入一金屬層2〇於 :觸窗36中，使金屬層2〇的高度約與犧牲層21等高。 述之金屬層20較佳的係使用無電極電鍍 1253121 (electr〇less platmg)技術，以在導電層ι〇上方鍍上一層金 屬，例如是鎳、銅或其他任何導電金屬，使填滿整個電性接 觸窗36。本發明之增加懸浮薄膜接腳強度的方法並不限定 使用無電極電鍍技術，以填滿電性接觸窗36，任何其他可 填滿電性接觸窗36之技術，例如是沈積、濺鍍等方法，其 均不脫離本發明之精神與範圍。 接著參閱第5圖，在犧牲層21上，形成底層介電層31， 此底層介電層31在金屬填滿的電性接觸窗36上方亦形成一 開孔51。芩閱第6圖，接著製作導電薄膜32，作為讀取電 路到懸浮薄膜上的紅外線感測材料的電性連接。 翏閱第7圖，製作並圖案化紅外線感測層33，並保留 鍍在電性接觸窗36上的紅外線感測層33的材料。參閱第8 圖，、形成上層介電層34,以保護紅外線感測層33中的紅外 線感測材料。參閱第9圖，定義懸浮薄膜與接腳的區域，並 2開犧牲層21的蝕刻窗35。接著參閱第1〇圖，藉由蝕刻 窗35以蝕刻掉犧牲層21，使懸浮薄膜接腳3〇懸空。其中， 懸浮薄膜接腳30由於僅需與金屬層2〇接觸，即可完成讀取 電路與導電薄膜32的電性耦合。因此，導電薄膜32無須深 ^電性接觸窗36中，來與導電層1〇直接接觸。因此，懸浮 _接腳30的強度因而提升’且更有助於確保電性的= 質 〇 曰習知的熱型紅外線焦面陣列元件的製作中，通常都會先 在曰3片上製作讀取電路，此讀取電路的表層有介電層保嗖， 然後在具有讀取電路的晶片基材上製作紅外線感測日的微機 1253121 電結構。首先係在讀取電路之上製作—齡層，並在此犧牲 層與基材中，形成一電性接觸窗曝露基材中的讀取電路的導 電層。但疋，由於電性接觸窗的深度比導電薄膜的厚度大报 ' 多，造成導電薄膜須深入電性接觸窗之中，其將導致電性接 觸良率的降低，且使導電薄膜的機械強度降低。 為了克服上述之缺點，本發明之增加懸浮薄膜接腳和基 材的連接點之強度的方法，在製作導電薄膜之前，即在電性 接觸囪中填入一金屬層，例如是以無電極電鍍形成此金_ φ 層。此金屬層，一般約為2μιη，材料例如是鎳，將填滿整個 電性接觸窗，並連接基材裏曝露出來的導電層。然後懸浮薄 膜接腳和讀取電路之電性連接點將被有效的提高至電性接 觸自的上方，不僅使得接腳和基材的連接點之力學結構增 強’也能確保電性的連接。 熱阻型的紅外線感測器之感測材料通常為釩氧化物 (VOx)，經由蝕刻此釩氧化物以形成紅外線感測薄膜◦本發 明增加懸浮薄膜接腳強度的方法更保留接腳和基材的連接 點上的熱阻型感測材料，因此，在約6〇〇人〜9〇〇人的導電薄 膜之上，再加上約lkA導電的熱阻型感測材料，接腳和基 材的連接點的電性連接更能得到保證，接腳和基材的連接點 的力學結構也可進一步加強。本發明更可保留連接點上方之 上層介電層，一方面保護保留的熱阻型感測材料，更進一步 加強接腳和基材的連接點之力學結構。 雖然本發明已以一較佳實施例揭露如上，然其並非用以 限定本發明，任何熟習此技藝者，在不脫離本發明之精神和 10 1253121 【圖式簡早說明】 為讓本發明之上述和其他目沾 θ的、特徵、優點與實施例能 更明顯易懂，所附圖式之詳細說明如下·· 浮薄膜接腳強度的方 第1〜10圖係為本發明之增加懸 法的流程示意圖。 【主要元件符號說明】1253121 IX. Description of the invention: [Technical field to which the invention pertains] The present invention relates to improving the production yield of an infrared sensor, and relates to a connection point for increasing the suspended film pin and the substrate. Strength' method to increase the yield of infrared sensors. [Prior Art] With the rapid advancement of the semiconductor industry and electronic technology, the manufacturing technology of infrared sensors is also progressing. Infrared sensors can not only be used in medical 'measurement of body temperature' but also in scientific, commercial and military, such as laser detection, missile guidance, infrared spectrometer, remote control, anti-theft device, thermal image Inspect for other purposes. The infrared sensor can be mainly divided into thermal type and lining type (ph〇t〇n): large class. Since the thermal infrared sensor is convenient to use, the general application is also extensive.钹 and θ, the thermal infrared sensor includes a thermocouple sensing, a pyrocouplenc sensor, and a thermal resistance type infrared sensor (m1Crobolometer). The thermocouple type infrared sensor, the thermopile 'structure is a series of series thermocouples, hot junction junctions, is arranged on the suspended film, and the cold junction (c〇M juncti〇n) is 棑Listed on the substrate, the pins between the suspended film and the substrate must pass through a series of thermocouple wires, so the pins are wide and the pins are usually short. The thermal resistance type infrared sensor uses a thermal sensing film having a high coefficient of temperature coefficient (TCR) to be fabricated on the suspension film of the sensor, and is formed by at least two pins. Suspended 1253121 floating film support is conducted over the substrate to the US material. ..., the electrical properties of the sensing film are also processed and processed by the two pins of the electric type. The coke drought is the use of a piece of coke film material, made in the sense ==. The suspension film of the thermal resistance type and the pyroelectric type sensing material, the requirements of the base of the substrate are all the same, basically, in the premise of the mechanics society Lai Qiang, in order to reduce the thermal conductivity (thermai_duetance): The fewer the feet, the longer, the narrower, the thinner the better. ί Suspension films and pins often have residual stresses due to process conditions. Suitable stresses can stress the structure, especially the joints of the structure. Joints Due to the different processes and materials used, the mechanical strength will be weaker, and if the stress is greater than the strength of the joint, the joint may break. At the same time, in order to make the connection between the pin and the substrate, the height of the pin must be lowered from the height of the suspended film to the surface of the conductive layer of the read circuit, but the conductive film on the pin is thin, so it is relatively fragile. Electrical connection. SUMMARY OF THE INVENTION In view of the foregoing prior art description, the conventional infrared sensor has a large difference in height due to the junction of the pin and the conductive layer of the read circuit, and the length of the pin relative to the tap and thickness of the pin. It is also very long, making the connection between the pin and the substrate very fragile, which in turn affects the production yield of the infrared sensor. Accordingly, it is an object of the present invention to provide a method of increasing the strength of the connection of the suspended film pins to the substrate to enhance the bonding strength of the pins of the infrared sensing film to the read circuitry in the substrate. 1253121 Another object of the present invention is to provide a method of increasing the strength of the joint between the suspended film pins and the substrate to increase the production yield of the infrared sensor. In accordance with the above objects, the present invention is directed to a method of increasing the strength of a connection point between a suspended film pin and a substrate, the method comprising the steps of first providing a read circuit wafer and then forming a read circuit wafer. A sacrificial layer is then formed in the sacrificial layer to form an electrical contact window and expose a conductive layer of the read circuit wafer. A metal layer is then filled in the electrical contact window and a conductive film is electrically coupled to the metal layer. Then, an infrared sensing layer and an upper dielectric layer are sequentially formed on the conductive film. When the patterned infrared sensing layer is patterned, the infrared sensing layer above the electrical contact window is retained. At the same time, when the upper dielectric layer is patterned, the upper dielectric layer above the infrared sensing layer above the electrical contact window is retained to protect the infrared sensing layer above the contact window. Wherein, before forming the above-mentioned conductive film and the infrared sensing layer, an underlying dielectric layer may be formed first. The sacrificial layer is etched using an etched window through the upper dielectric layer and the lower dielectric layer to vacate the suspended film. The above-mentioned sacrificial material is a poly (four)' metal layer $ which can be processed by a subtractive electric ore recording process to fill the metal layer in the electrical contact window. The method for increasing the strength of the connection between the suspension film pin and the substrate of the present invention enhances the strength of the connection point of the suspension film pin of the thermal infrared sensor and the substrate, and further improves the pin and the substrate. The electrical connection of the connection point can be further protected and the strength of the connection point between the pin and the substrate can be further increased by using the infrared sensing layer above the retention electrical contact window and the upper layer 'I electrical layer'. 1253121 The thermal infrared sensor, especially the thermal resistance type infrared sensor, not only improves the production yield, but also effectively improves its electrical quality. [Embodiment] The method for increasing the strength of the connection point of the suspension film pin and the substrate of the present invention is effective to increase the electrical bonding strength of the infrared sensing film pin and the reading circuit in the substrate, and to increase the pin and The mechanical strength of the connection point of the substrate can improve the yield of the infrared sensor when it is produced. The spirit and scope of the present invention will be apparent from the following description and the detailed description of the present invention, which can be modified and modified by the teachings of the present invention. It does not depart from the spirit and scope of the invention. The first 10th figure is the method for increasing the strength of the suspended film pin of the present invention: the non-thinking is based on the reading circuit 曰a piece of a thermal infrared focal plane array element as an example to increase the suspension of the present invention. The film pin strength is more than the first drawing of the thermal infrared focal plane array component read circuit on the wafer first formed conductive | 10, such as Ming, Ming copper, or (four) copper alloy, and the protection of the read circuit Electrical layer ii. Next, referring to Fig. 2, a sacrificial layer 2 is formed, for example, a polyimide, and the sacrificial layer 21 has an opening 22 above the conductive layer 1?. The second layer 3 reads the dielectric layer u of the circuit, and the opening 22 reaches the conductive layer 10. The opening 22 forms an infrared sensing film pin to the electrical contact window 36 of the substrate. Referring to Fig. 4_, a metal layer 2 is filled in the contact window 36 such that the height of the metal layer 2 is approximately the same as that of the sacrificial layer 21. The metal layer 20 is preferably electrolessly plated with 1253121 (electr〇less platmg) technology to coat a layer of metal, such as nickel, copper or any other conductive metal, over the conductive layer to fill the entire electricity. Sexual contact window 36. The method of the present invention for increasing the strength of the suspended film pins does not limit the use of electroless plating techniques to fill the electrical contact windows 36, any other technique that can fill the electrical contact windows 36, such as deposition, sputtering, etc. They do not depart from the spirit and scope of the invention. Referring to FIG. 5, on the sacrificial layer 21, an underlying dielectric layer 31 is formed. The underlying dielectric layer 31 also defines an opening 51 above the metal filled electrical contact window 36. Referring to Figure 6, a conductive film 32 is then formed as an electrical connection of the read circuit to the infrared sensing material on the suspended film. Referring to Figure 7, the infrared sensing layer 33 is fabricated and patterned, and the material of the infrared sensing layer 33 plated on the electrical contact window 36 is retained. Referring to FIG. 8, an upper dielectric layer 34 is formed to protect the infrared sensing material in the infrared sensing layer 33. Referring to Figure 9, the area of the suspended film and the pins is defined, and the etching window 35 of the sacrificial layer 21 is opened. Referring to Fig. 1 again, the sacrificial layer 21 is etched away by etching the window 35 to suspend the suspended film pins 3'. The suspension film pin 30 can be electrically coupled to the conductive film 32 by only contacting the metal layer 2〇. Therefore, the conductive film 32 does not need to be in the deep contact window 36 to be in direct contact with the conductive layer 1A. Therefore, the strength of the suspension_pin 30 is thus improved, and it is more helpful to ensure electrical properties. In the fabrication of a conventional thermal-type infrared focal plane array component, a read circuit is usually fabricated on the 曰3 wafer. The surface of the read circuit has a dielectric layer protection, and then an infrared sensing system 1253121 is fabricated on the wafer substrate having the read circuit. First, an ageing layer is formed on the read circuit, and an electrically conductive layer is formed in the sacrificial layer and the substrate to form a conductive layer for exposing the read circuit in the substrate. However, since the depth of the electrical contact window is greater than the thickness of the conductive film, the conductive film must penetrate into the electrical contact window, which will result in a decrease in the electrical contact yield and the mechanical strength of the conductive film. reduce. In order to overcome the above disadvantages, the method for increasing the strength of the connection point between the suspension film pin and the substrate of the present invention is to fill a metal layer in the electrical contact bake before the electroconductive film is formed, for example, electroless plating. This gold _ φ layer is formed. The metal layer, typically about 2 μm, of material such as nickel, will fill the entire electrical contact window and connect the exposed conductive layer in the substrate. Then, the electrical connection points of the suspension film pins and the read circuit are effectively raised to the upper side of the electrical contact, which not only enhances the mechanical structure of the connection point of the pin and the substrate, but also ensures electrical connection. The sensing material of the thermal resistance type infrared sensor is usually vanadium oxide (VOx), and the vanadium oxide is etched to form an infrared sensing film. The method for increasing the strength of the suspended film pin of the invention further retains the pin and the base. The thermal resistance type sensing material on the connection point of the material, therefore, on the conductive film of about 6 〜 to 9 〇〇, plus about lkA conductive thermal resistance type sensing material, pin and base The electrical connection of the connection points of the materials can be ensured, and the mechanical structure of the connection points of the pins and the substrate can be further strengthened. The invention further preserves the upper dielectric layer above the connection point, and on the one hand protects the retained thermal resistance type sensing material, and further strengthens the mechanical structure of the connection point of the pin and the substrate. The present invention has been described above with reference to a preferred embodiment, and is not intended to limit the invention, and the skilled in the art, without departing from the spirit of the invention and 10 1253121. The above and other objects, features, advantages and embodiments of the present invention can be more clearly understood, and the detailed description of the drawings is as follows: The first to tenth figures of the floating film pin strength are the additional suspension method of the present invention. Schematic diagram of the process. [Main component symbol description]
10 導電層 20 金屬層 22 開孔 31 底層介電層 33 紅外線感測層 35 蝕刻窗 51 開孑L 11 :介電層 21 :犧牲層 30 :懸浮薄膜接腳 32:導電薄膜 34:上層介電層 36:電性接觸窗10 Conductive layer 20 Metal layer 22 Opening 31 Underlying dielectric layer 33 Infrared sensing layer 35 Etching window 51 Opening L 11 : Dielectric layer 21: Sacrificial layer 30: Suspended film pin 32: Conductive film 34: Upper dielectric Layer 36: electrical contact window