五 經濟部中央標準局員工消費合作社印裝 A7 B7 發明説明（l ) 發明領域 本發明與半導體元件有關，更詳細說，與在半導體元 件上成形球栅陣列接點有關。 發明背景 近年來，積體電路為了符合高性能的要求，積體電路 的密度不斷增加。同樣為了符合高性能的要求，積體電路 的封裝體積也愈來愈小，致使封裝需要較高的接腳密度。 接腳密度愈高，I/O連接引線的間距也更細微。球柵陣列 封裝(BGA封裝)符合高密度接腳的要求，且由於BGA優於 傳統的方扁平封裝(QFP封裝），因此可用以取代目前的QFP 封裝。 BGA封裝的共面問題較小，具有自準直的能力，良 品率也比QFP封裝高。目前有很多種球附著的技術可供選 用，但製作球附著的過程都很複雜，而且很難在基材上得 到均勻的球體。 球附著製程的例子之一是使用散佈機(dispensing machine)在基材上散佈焊料(solder paste)。布列於基材上 之焊球的體積不同，其所含的金屬成分也有差異。焊球的 高度也很難控制。散布法的生產力很低，但主要的問題還 是焊球的高度不夠。 另一種製程是附著預先成形的球。此有兩種方法，一 是塑膠封裝，另一是陶瓷封裝。低鎔點的焊球使用塑膠 BGA封裝，高鎔點焊球使用陶瓷BGA封裝。 -3- 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐） II 1 (. ^^^^1 I ml nn ml (請先閲讀背面之注意事項再填寫本頁) 經濟部中央標準局員工消費合作社印裝 A7 ------------B7 五、發明説明（2 ) 還有一種製程是用焊線黏接(bond)構成BGA球。束線 將結合在基材的引線墊上。此種製程的生產力也低，也有 焊球高度的問題。 以上所有製作方法都不能保證球的高度與大小一致， 且無法令半導體表面上的每個球都在它所該在的位置。 發明概述 本發明是在球栅陣列半導體元件的接點區成形焊接點 的方法。半導體先經預、熱，從焊料片上將許多預成形的焊 料模型直接沖到半導體基材的接點區上。基材與焊料被加 熱以使焊料回流，在半導體基材上形成接點。 從以下對本發明之較佳具體實例的描述，並配合所附 圖式’以及所附之申請專利範圍中所述的創新特徵，將可 瞭解本發明技術的進步以及它的目的。 圖式簡述 圖1顯示半導鱧元件與球柵陣列接點； 圖2顯示一個半導體元件在一丨中針下方，沖針將焊料 預成形於基材上； 圖3顯示預成形焊料的基材； 圖4是基材上已成形焊料的等視圖； 圖5顯示焊料回流後的基材與焊球； 圖6顯示焊球附著於基材之上； 圖7顯示焊料模形附著於基材上； -4- 本紙張尺度適用中國國家標準（CNS ) A4規格（210X 297公釐) ~ --- ---------ά------IT (請先聞讀背面之注意事項再填寫本頁) 經濟部中央梂準局員工消費合作社印製 A 7 B7 五、發明説明（3 ) 圖8是成形與附著焊料接點之製程的第一種具體實例 流程圖； 基材上製做與放置焊球之製程的第二種具體 實例。 較佳具體實例描述 圖1所示的半導體元件ίο包括基材η以及焊球接點12 的陣列。每一個焊球附著於焊球下方的接點（見圖4)。接 點可能是一延伸入基材11内的通道，接觸到半導體晶片上 的單元，亦或是在基材上的導體，與其它電路或半導體元 件上的接整連接。 圖2顯示一固定於載台15上的半導體基材16，並位於 有很多沖針19的沖模18下方，沖模與基材間是帶狀或捲狀 的焊料片17。半導體基材16置於沖模18的下方後啟動沖模 18，沖針19沖出許多焊料模型2〇(見圖3)。在圖3中，焊料 模型20整齊排列於基材16之上。 圖4顯示半導體基材16與沖出的焊料模型20位於區域 21之上。每一個接點區21可能是一延伸入基材16内的通道 ，接觸到半導體晶片上的單元，亦或是在基材上的導體， 與其它電路或半導體元件上的接墊連接。 在沖焊料片17前，每一個接點區21都先塗上一層助焊 劑。接點區21間的區域22則沒有助烊劑。圖中焊料模型20 的形狀是一立方體或長方體，不過，它可為任何所需的幾 何形狀。 -5- 本紙張尺度適用中國國家梂準（CNS ) A4規格（210X297公釐） (靖先閱讀背面之注意事項再填寫本頁) 丁 經濟部中央標準局員工消費合作社印製 A7 ________B7 五、發明説明（4 ) 圖5顯示基材16與焊料模型2〇加熱後致焊料鎔化與回 流形成的烊球20a與基材16 〇僅接點區21被焊料所浸，且 由於焊料的表面張力，使得鎔化的焊料模型2〇形成一圓球 狀’構成球柵陣列半導體元件的接點。 焊料片17的厚度均勻’其成分可為9〇/1〇的錫/鉛，或 63/37的錫/錯。厚度則視接點所需的高度而定。 基本製程隨焊料成分稍有差異。視焊料的種類，回流 期間焊料模型可能不會完全被鎔化。低鎔點焊料或助焊劑 可置於基材的接點區上。如果焊料片是低鎔點焊料，那麼 置於每一個接點區的助焊劑層用來清除接點區的氧化物。 在使用助焊劑時，助焊劑的黏度非常重要。在回流期間， 高黏度的助焊劑能使焊料模型保持在接點區上不移動。所 使用的助焊劑大小可為325-500 mesh。 在焊料模型被沖於基材的接點區上之後，基材與焊料 模型被加熱以使焊料回流。基材與焊料模型被加熱的溫度 範園大約為150-225°C。回流的時間大約為3.5至5.5分。 圖6是一個固定於基材上之焊球的側視圖，圖7是高溫 焊料模型的侧視圖。在圖6中，顯示回流的焊球31是由低 溫焊料所製成。基材30與回流成形附著於基材3〇上的焊球 31。在焊球的底部有一圈fliiet32。 圖7中是使用高溫的焊料模型做為接點。在回流期間 ’僅低嫁點的焊料被鎔化，將焊料模型焊於接點區上。加 溫與回流製程可在氮氣的環境中進行。圖7顯示基材35與 附著於基材35上的高溫焊料模型36。低溫焊料37將焊料模 -6 - 本紙張尺度適用中國國家標準（CNS ) A4規格（210X297公釐）5. Printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs A7 B7 Description of the Invention (1) Field of the Invention The present invention relates to semiconductor elements, and more specifically, to the formation of ball grid array contacts on semiconductor elements. BACKGROUND OF THE INVENTION In recent years, in order to meet the requirements of high performance, the density of integrated circuits has been increasing. Also in order to meet the requirements of high performance, the package volume of integrated circuits is getting smaller and smaller, resulting in a higher pin density required for the package. The higher the pin density, the finer the pitch of the I / O connection leads. Ball grid array package (BGA package) meets the requirements of high-density pins, and because BGA is superior to traditional square flat package (QFP package), it can be used to replace the current QFP package. The BGA package has less coplanarity problems, has the ability of self-collimation, and has a higher yield than the QFP package. At present, there are many kinds of ball attachment technologies to choose from, but the process of making the ball attachment is very complicated, and it is difficult to obtain a uniform ball on the substrate. One example of a ball attachment process is the use of a dispensing machine to spread a solder paste on a substrate. Depending on the volume of the solder balls arranged on the substrate, the metal content of the solder balls also varies. The height of the solder balls is also difficult to control. The productivity of the dispersion method is low, but the main problem is that the height of the solder balls is not enough. Another process involves attaching pre-formed balls. There are two methods, one is plastic packaging, and the other is ceramic packaging. The low bump solder balls are packaged in plastic BGA, and the high bump solder balls are packaged in ceramic BGA. -3- This paper size applies to Chinese National Standard (CNS) A4 (210X297 mm) II 1 (. ^^^^ 1 I ml nn ml (Please read the precautions on the back before filling this page) Central Standard of the Ministry of Economic Affairs Bureau employee consumer cooperative printing A7 ------------ B7 V. Invention description (2) There is also a process of bonding BGA balls with bonding wires. The beam lines will be combined in the base Material on the lead pad. The productivity of this process is also low, and there is also the problem of the height of the solder balls. All the above manufacturing methods cannot guarantee that the height and size of the balls are consistent, and that each ball on the semiconductor surface cannot be where it should Summary of the Invention The present invention is a method for forming solder joints in the contact area of a ball grid array semiconductor element. The semiconductor is pre-heated, and many pre-shaped solder models are directly punched from the solder wafer to the contacts of the semiconductor substrate. Area. The substrate and the solder are heated to reflow the solder to form a contact on the semiconductor substrate. From the following description of the preferred embodiment of the present invention, and in conjunction with the accompanying drawings' and the scope of the attached patent application The innovative features described The technical progress of the present invention and its purpose can be understood. Brief Description of the Drawings Figure 1 shows the junction between a semiconductor element and a ball grid array; Figure 2 shows a semiconductor element under a middle pin, and a punch pin pre-shapes the solder on On the substrate; Figure 3 shows the preformed solder substrate; Figure 4 is an isometric view of the formed solder on the substrate; Figure 5 shows the substrate and solder balls after solder reflow; Figure 6 shows the solder balls attached to the substrate Figure 7 shows that the solder mold is attached to the substrate; -4- This paper size applies the Chinese National Standard (CNS) A4 specification (210X 297 mm) ~ --- --------- ά- ----- IT (Please read the precautions on the back before filling out this page) Printed by the Consumers' Cooperative of the Central Government Bureau of the Ministry of Economic Affairs A 7 B7 V. Description of the invention (3) Figure 8 shows the forming and soldering joints The first specific example flowchart of the manufacturing process; the second specific example of the manufacturing and placing of solder balls on the substrate. The preferred embodiment describes the semiconductor device shown in FIG. 1 including the substrate η and the solder ball connection. An array of points 12. Each solder ball is attached to a contact below the solder ball (see Figure 4). The contacts may be A channel extending into the substrate 11 contacts a unit on a semiconductor wafer, or a conductor on the substrate, and is connected to other circuits or semiconductor components. Fig. 2 shows a fixed stage 15 The semiconductor substrate 16 is located below the die 18 with a lot of punch pins 19, and there is a strip-shaped or rolled solder piece 17 between the die and the substrate. After the semiconductor substrate 16 is placed under the die 18, the die 18 is started and punched. The pins 19 punch out many solder patterns 20 (see FIG. 3). In FIG. 3, the solder patterns 20 are neatly arranged on the substrate 16. FIG. 4 shows that the semiconductor substrate 16 and the punched solder patterns 20 are located in the region 21. on. Each contact area 21 may be a channel extending into the substrate 16, contacting a unit on the semiconductor wafer, or a conductor on the substrate, and connecting with other circuits or pads on the semiconductor element. Before punching the solder sheet 17, each contact area 21 is coated with a layer of flux. The area 22 between the contact areas 21 is free of tincture. The shape of the solder model 20 in the figure is a cube or a cuboid, however, it may have any desired geometric shape. -5- This paper size applies to China National Standards (CNS) A4 (210X297 mm) (Jing first read the precautions on the back before filling out this page) D7 Printed by the Consumer Cooperatives of the Central Standards Bureau of the Ministry of Economic Affairs Explanation (4) FIG. 5 shows that the ball 20a and the substrate 16 formed by the soldering and reflow of the substrate 16 and the solder model 20 after heating are heated. Only the contact area 21 is immersed in the solder, and due to the surface tension of the solder, The halogenated solder model 20 is formed into a spherical shape, which constitutes the contact point of the semiconductor device of the ball grid array. The thickness of the solder sheet 17 is uniform ', and its composition may be tin / lead of 90/10, or tin / lead of 63/37. The thickness depends on the required height of the contact. The basic process varies slightly with solder composition. Depending on the type of solder, the solder model may not be fully cured during reflow. Low puddle solder or flux can be placed on the contact area of the substrate. If the solder chip is a low-blade solder, a flux layer placed at each contact area is used to remove oxides from the contact area. When using flux, the viscosity of the flux is very important. During reflow, a high-viscosity flux can keep the solder pattern on the contact area from moving. The flux used can be 325-500 mesh. After the solder pattern is punched onto the contact area of the substrate, the substrate and the solder pattern are heated to reflow the solder. The temperature at which the substrate and solder model are heated is about 150-225 ° C. The reflow time is approximately 3.5 to 5.5 minutes. Fig. 6 is a side view of a solder ball fixed to a substrate, and Fig. 7 is a side view of a high-temperature solder model. In Fig. 6, the reflowed solder ball 31 is made of a low-temperature solder. The base material 30 and the solder balls 31 attached to the base material 30 are formed by reflow molding. There is a circle of fliiet32 at the bottom of the solder ball. In Figure 7, a high temperature solder model is used as the contact. During reflow, 'only the low-married solder is agitated and the solder pattern is soldered to the contact area. The heating and reflux processes can be performed in a nitrogen atmosphere. Fig. 7 shows the base material 35 and the high-temperature solder model 36 attached to the base material 35. Low-temperature solder 37 will solder mold -6-This paper size applies to China National Standard (CNS) A4 specification (210X297 mm)
Hi in n n -- I - I . n ml *T (請先閲讀背面之注意事項再填寫本頁) A7 ___B7 五、發明説明（5 ) 型36附著於基材35之上。 形成焊球的製程顯示於圖8。準備基材(45)，例如清 潔基材表面及在接點區上施加助焊劑，焊球即成形與附著 於這些接點區。將基材加熱(46)到助焊劑的鎔點。沖焊料 片（47)，例如63/37的錫/鉛焊料，在氮氣環境中直接置於 基材的接點區上。焊料回流與形成焊球(48)。 圖9顯示第二種具體實例。準備基材(5〇)，並在基材 的接點區上施加助焊劑(51)。沖焊料片（52)，例如成分90/K) 的錫/鉛或63/37的錫/錯直接沖於基材上。將基材加熱到烊 料回流(53)以形成焊料接點。最後清潔基材(54)。 ^^1 H· ^ϋ— l 1^1 nn In 1 m ^^^1 n^i - J. -8 (請先閲讀背面之注意事項再填寫本頁) 經濟部中央標準局員工消費合作社印製 本紙張尺度適用中國國家榡準（CNS ) A4規格（2丨οχ297公釐）Hi in n n-I-I. N ml * T (Please read the precautions on the back before filling this page) A7 ___B7 V. Description of the invention (5) Type 36 is attached to the substrate 35. The process of forming solder balls is shown in FIG. 8. A substrate (45) is prepared, for example, the surface of the substrate is cleaned and a flux is applied to the contact areas, and solder balls are formed and attached to the contact areas. The substrate is heated (46) to the spot of the flux. A solder chip (47), such as 63/37 tin / lead solder, is placed directly on the contact area of the substrate in a nitrogen atmosphere. Solder reflow and formation of solder balls (48). Figure 9 shows a second specific example. A substrate (50) is prepared, and a flux (51) is applied to a contact area of the substrate. The solder sheet (52), for example, tin / lead of composition 90 / K) or tin / lead of 63/37 is directly punched on the substrate. The substrate is heated to the solder reflow (53) to form a solder joint. Finally, the substrate (54) is cleaned. ^^ 1 H · ^ ϋ— l 1 ^ 1 nn In 1 m ^^^ 1 n ^ i-J. -8 (Please read the notes on the back before filling this page) The paper size of the paper is applicable to China National Standard (CNS) A4 (2 丨 οχ297 mm)