201010819 九、發明說明： 【發明所屬之技術領域】 本發明係有關於-種銅製銲線，更特別有關於一種鲜 線接合結構，其之塊狀部為中間材料所覆蓋且該中間材 料接合於該塊狀部及一接墊。 【先前技術】 參考第1圖’在半導體封裝構造製程中，銲線接合方法 •的技術廣泛地將銲線14應用於晶片1〇之接塾u與基板 12之接墊13間的電性連接。打線接合製程是以金線為主， 但銅線具有低成本的優勢。相較於金，銅具有較佳的導電 性及導熱性，可使銅製銲線之線徑較細及散熱效率較佳。 然而，銅具有延性不足及易氧化的缺點，使銅製銲線在應 用上仍有所限制。 目則’銅製銲線只能應用在大尺寸之晶片接塾或低介電 值材料（low-K)晶圓之晶片接墊，其原因在於銅製銲線接合 籲製程之成功將取決於晶片接藝之結構強度。為了避免銅製 銲線接合製程之失敗，小尺寸晶片接墊將被限制。 參考第2至4圖’其顯示習知銅製銲線接合方法。參考 第2圖，藉由一打線機’提供一銅製銲線2〇，其包含一銅 線22及一銅球24 »該銅球24是利用放電的方法或氫焰燒 結成球而連接於該銅線22之一端》參考第3圖，將該銅球 24施壓而變形。參考第4圖，藉由一振動製程，將該銅球 24接合於一鋁製接墊32。然而，在施壓製程時，由於銅之 硬度較大，因此施壓時銅製銲線20所造成之力將可能損壞 〇1346-TW/ASE213i5 5 201010819 鋁製接墊32之結構。再者，先前技術之鋁製接墊32與銅 輝線〇之間的介金屬化合物（intermetallic compound; MC)所形成之數量不足，因此先前技術之銲線接合結構具 有較小的鍵結力，進而只具有較低的可靠度。 因此，便有需要提供一種銅製銲線，能夠解決前述的缺 點。 【發明内容】 φ 本發月< 目的在於提供一種銅製銲線，其之塊狀部為 中間材料所覆蓋。 本發明之另一目的在於提供一種銲線接合結構，其之中 間材料接合於一鋼製銲線及一接墊之間〆 為達上述目的，本發明提供一種銲線接合結構，其包含 -銅製銲線、—中間材料及—接塾。該銅製銲線包含一線 狀邛及塊狀部，其中該塊狀部連接於該線狀部，且該塊 狀部之剖面面積大於該線狀部之剖面面積。該中間材料覆 • 蓋一部份之該塊狀部，並接合於該塊狀部。該接墊接合於 該中間材料。 根據本發明之銲線接合方法，在施壓製程時，銅製銲線 所造成之力將不會損壞接墊之結構。再者，相較於先前技 術本發明之銲線接合結構具有較大的鍵結力，進而具有 較高的可靠度。 為了讓本發明之上述和其他目的、特徵、和優點能更明 顯，下文將配合所附圖示，作詳細說明如下。 01346-TW/ASE2135 201010819 【實施方式】 參考第5至8圖，其顯示本發明之第_實施例之銅製銲 線接合方法。參考第5圖，藉由一打線機m，提供—銅 製銲線120,其包含一線狀部122及一塊狀部124，其中該 塊狀部m連接於該線狀部122之一端，且該塊狀部124 之剖面面積大於該線狀部122之剖面面積。該塊狀部124 可為球形》舉例而言，該塊狀部124是利用放電的方法或 鲁 氫焰燒結成球而連接於該線狀部1 22之一端。 參考第6圖’可藉由一沾黏製程，將一中間材料覆 蓋一部份之該塊狀部124。舉例而言，首先該中間材料14〇 可為粉末固體或液體型態，其置放於一容器142内。然後， 將該塊狀部124插人該容器142内，使粉末固體或液體塑 態之中間材料14〇沾黏於該塊狀部124上如此以覆蓋一 部份之該塊狀部124、較佳地，該塊散部124被該中間材 料140所覆蓋之面積大於30%之該塊狀部124的整個面 積。參考第7®，藉由-施壓製程，將該塊狀部124及該 雩中間材料140接觸於一接墊132，並施壓而變形。由於該 中間材料14〇介於該塊狀部124與詩132之間作為施壓 緩衝之用’因此施壓時該塊狀部124所造成之力將不會損 壞接塾132之結構。參考第8圖，可藉由一振動製程，將 該塊狀部124接合於該中間材料14〇，且同時將該中間材 料140接合於該接墊132，如此以形成本發明之銲 A1- Lit 卜 TtC 口 結構。 另外，本發明之銲線接合結構可應用於一半導體封裝構 01346-TW/ASE2135 7 201010819 造之晶片’亦即該接墊i 32可為一晶片接墊，且該銅製銲 線之一端電性連接於該晶片接墊，該銅製銲線之另一端電 f生連接於一基板接塾（如第1圖所示該晶片接塾電性連 接於該晶片之線路（圖未示）。 在本實施例中，該接墊132為鋁所製，且該中間材料 140 選自錫（Sn)、金（Au)、辞（Zn)' 鉑（Pt)、鈀（Pd)、錳（Μη)、 鎮（Mg)、銦（in)、鍺（Ge)及銀（Ag)所構成之群組。該中間材 料140與銅製銲線12〇之間的介金屬化合物所形成之數量 ® 大於該鋁製接墊與銅製銲線之間的介金屬化合物所形成之 數量’且該中間材料14〇與鋁製接墊132之間的介金屬化 合物所形成之數量大於該鋁製接墊132與銅製銲線12〇之 間的介金屬化合物所形成之數量。因此，該中間材料140 與鋼製銲線120之間的鍵結力大於該鋁製接墊132與銅製 銲線120之間的鍵結力，且該中間材料14〇與鋁製接墊 之間的鍵結力大於該鋁製接墊132與銅製銲線12〇之間的 鍵結力。 瘳 根據本發明之銲線接合方法，在施壓製程時，由於該中 間材料介於該塊狀部與接墊之間作為施壓緩衝之用因此 銅製銲線所造成之力將不會損壞接墊之結構。再者，相較 於先前技術’本發明之銲線接合結構具有較大的鍵結力， 進而具有較高的可靠度。 參考第9a及9b至11圖，其顯示本發明之第二實施例 之銅製銲線接合方法。參考第9a及9b圖，藉由一打線機 202，提供一銅製銲線22〇，其包含一線狀部222及一塊狀 01346-TW/ASE2135 8 201010819 部224，其中該塊狀部224連接於該線狀部222之-端， 且該塊㈣224之剖面面積大於該線狀冑222之剖面面 積。該塊狀部224可為非球形》舉例而言，在本實施例中， 該塊狀部224先利用放電的方法或氫焰燒結成球而連接於 該線狀部2 2 2之一^娃 αν /λ , 鳊。…、後，藉由一施壓製程，將該塊狀 β201010819 IX. DESCRIPTION OF THE INVENTION: TECHNICAL FIELD The present invention relates to a copper wire bonding wire, and more particularly to a wire bonding structure in which a block portion is covered with an intermediate material and the intermediate material is bonded to The block portion and a pad. [Prior Art] Referring to FIG. 1 'In the semiconductor package structure manufacturing process, the wire bonding method is widely used to apply the bonding wire 14 to the electrical connection between the substrate 1 of the wafer and the pad 13 of the substrate 12. . The wire bonding process is mainly gold wire, but the copper wire has the advantage of low cost. Compared with gold, copper has better electrical conductivity and thermal conductivity, which makes the copper wire have a smaller wire diameter and better heat dissipation efficiency. However, copper has the disadvantages of insufficient ductility and susceptibility to oxidation, which makes copper wire bonding still limited in application. The copper wire can only be used on wafer pads of large size wafers or low-k materials, because the success of the copper wire bonding process will depend on the wafer connection. The structural strength of the art. In order to avoid the failure of the copper wire bonding process, small size wafer pads will be limited. Referring to Figures 2 to 4, there is shown a conventional copper wire bonding method. Referring to FIG. 2, a copper bonding wire 2' is provided by a wire bonding machine, which comprises a copper wire 22 and a copper ball 24. The copper ball 24 is connected to the ball by a discharge method or a hydrogen flame sintered ball. One end of the copper wire 22 refers to FIG. 3, and the copper ball 24 is pressed and deformed. Referring to Fig. 4, the copper ball 24 is joined to an aluminum pad 32 by a vibration process. However, during the pressing process, due to the high hardness of the copper, the force caused by the copper bonding wire 20 during the pressing may damage the structure of the aluminum pad 32 of the 1346-TW/ASE213i5 5 201010819. Furthermore, the amount of the intermetallic compound (MC) between the prior art aluminum pad 32 and the copper wire enthalpy is insufficient, so that the prior art wire bonding structure has a small bonding force, and thus Only has low reliability. Therefore, there is a need to provide a copper bonding wire which can solve the aforementioned drawbacks. SUMMARY OF THE INVENTION φ This is a month of the present invention. The object of the present invention is to provide a copper bonding wire whose block portion is covered by an intermediate material. Another object of the present invention is to provide a wire bonding structure in which an intermediate material is bonded between a steel bonding wire and a pad. To achieve the above object, the present invention provides a wire bonding structure comprising - copper Welding wire, intermediate material and joint. The copper bonding wire includes a wire-like ridge and a block portion, wherein the block portion is connected to the wire portion, and a cross-sectional area of the block portion is larger than a cross-sectional area of the wire portion. The intermediate material covers a portion of the block and is joined to the block. The pad is bonded to the intermediate material. According to the wire bonding method of the present invention, the force caused by the copper bonding wire does not damage the structure of the pad during the pressing process. Furthermore, the wire bonding structure of the present invention has a larger bonding force than the prior art, and thus has higher reliability. The above and other objects, features, and advantages of the present invention will become more apparent from the accompanying drawings. 01346-TW/ASE2135 201010819 [Embodiment] Referring to Figures 5 to 8, there is shown a copper wire bonding method of the first embodiment of the present invention. Referring to FIG. 5, a wire bonding wire 120 is provided by a wire bonding machine m, which includes a linear portion 122 and a block portion 124, wherein the block portion m is connected to one end of the linear portion 122, and The cross-sectional area of the block portion 124 is larger than the cross-sectional area of the linear portion 122. The block portion 124 may be spherical. For example, the block portion 124 is connected to one end of the linear portion 1 22 by a method of discharging or a sintered hydrogen flame into a ball. Referring to Fig. 6, an intermediate material may be covered by a portion of the block portion 124 by a sticking process. For example, first the intermediate material 14A can be in a powder solid or liquid form, which is placed in a container 142. Then, the block portion 124 is inserted into the container 142, and the powder solid or liquid plastic intermediate material 14 is adhered to the block portion 124 so as to cover a portion of the block portion 124, Preferably, the area of the bulk 124 covered by the intermediate material 140 is greater than 30% of the entire area of the block 124. Referring to Fig. 7®, the block portion 124 and the crucible intermediate material 140 are brought into contact with a pad 132 by a pressing process, and are deformed by applying pressure. Since the intermediate material 14 is interposed between the block portion 124 and the poem 132 as a pressure buffer, the force caused by the block portion 124 during the pressing will not damage the structure of the joint 132. Referring to FIG. 8, the block portion 124 can be bonded to the intermediate material 14A by a vibration process, and at the same time the intermediate material 140 is bonded to the pad 132, thereby forming the solder A1-Lit of the present invention. Bu TtC port structure. In addition, the wire bonding structure of the present invention can be applied to a semiconductor package 01346-TW/ASE2135 7 201010819. The pad i 32 can be a wafer pad, and the copper wire is electrically terminated. Connected to the die pad, the other end of the copper bond wire is electrically connected to a substrate interface (as shown in FIG. 1 , the chip is electrically connected to the circuit of the chip (not shown). In the embodiment, the pad 132 is made of aluminum, and the intermediate material 140 is selected from the group consisting of tin (Sn), gold (Au), bis (Zn)' platinum (Pt), palladium (Pd), manganese (Mn), a group of towns (Mg), indium (in), germanium (Ge), and silver (Ag). The amount of intermetallic compound formed between the intermediate material 140 and the copper bonding wire 12〇 is greater than that of the aluminum The amount of the intermetallic compound formed between the pad and the copper bonding wire is 'the amount of the intermetallic compound between the intermediate material 14〇 and the aluminum pad 132 is greater than the aluminum pad 132 and the copper bonding wire. The amount of intermetallic compound formed between 12 turns. Therefore, the bond between the intermediate material 140 and the steel bond wire 120 It is larger than the bonding force between the aluminum pad 132 and the copper bonding wire 120, and the bonding force between the intermediate material 14〇 and the aluminum pad is greater than the aluminum pad 132 and the copper bonding wire 12 Bonding force between the two. According to the wire bonding method of the present invention, the copper bonding wire is caused by the intermediate material being interposed between the block portion and the pad as a pressure buffer during the pressing process. The force will not damage the structure of the pad. Moreover, compared with the prior art, the wire bonding structure of the present invention has a large bonding force and thus has high reliability. Referring to Figures 9a and 9b to 11 A copper bonding wire bonding method according to a second embodiment of the present invention is shown. Referring to Figures 9a and 9b, a wire bonding wire 22 is provided by a wire bonding machine 202, which includes a wire portion 222 and a block shape 01346. - TW / ASE2135 8 201010819 portion 224, wherein the block portion 224 is connected to the end of the linear portion 222, and the cross-sectional area of the block (four) 224 is larger than the cross-sectional area of the linear portion 222. The block portion 224 can be Non-spherical, for example, in the present embodiment, the block portion 224 first utilizes a discharge Hydrogen flame method or a sintered balls connected to the one of the linear portion 222 ^ baby αν / λ, bream, ..., after, by a pressing process, the block β
Ρ 224接觸於外部工具252之非黏性表面25〇，並施壓 而變形成該非球形塊狀部224，如第1〇圖所示。該非球形 塊狀部22:具有一平坦或粗糙之底面226，如第圖所示。 或者另藉由-夾擠製程，利用_夾擠卫具254將該非球 形塊狀4 224 左右方向（如箭頭所示）夾擠而變形成另一 種非球形塊狀部224，第11圖所示。該非球形塊狀部224 具有兩個或四個平坦之側面228,如第处圖所示。 參考第12圖，可藉由一沾黏製程，將一中間材料24〇 覆蓋一部份之該塊狀部224 〇舉例而言，首先該中間材料 240可為粉末固體或液體型態，其置放於一容器242内。 然後，將該塊狀部224插入該容器242内，使粉末固體或 液體型態之中間材料240沾黏於該塊狀部224上，如此以 覆蓋一部份之該塊狀部224。較佳地，該塊狀部224被該 中間材料240所覆蓋之面積大於3〇%之該塊狀部224的整 個面積〇參考第13圖，可藉由一振動製程，將該塊狀部 224接合於該中間材料240，且同時將該中間材料24〇接合 於一接墊232，如此以形成本發明之銲線接合結構。 在本實施例中’該接墊232為鋁所製，且該中間材料 240 選自錫（Sn)、金（Au)、鋅（Ζη)、鉑（pt)、鈀（Pd)、錳（Μη)、 鎂（Mg)、銦（In)、鍺（Ge)及銀（Ag)所構成之群組。該中間材 01346-TW/ASE2135 9 201010819 料240與銅製銲線22〇之間的介金屬化合物所形成之數量 大於該鋁製接墊與銅製銲線之間的介金屬化合物所形成之 數量，且該中間材料24〇與鋁製接墊232之間的介金屬化 合物所形成之數量大於該鋁製接墊232與銅製銲線22〇之 間的介金屬化合物所形成之數量。因此，該中間材料24〇 與銅製銲線220之間的鍵結力大於該鋁製接墊232與銅製 銲線220之間的鍵結力，且該中間材料240與鋁製接墊232 之間的鍵結力大於該鋁製接墊232與銅製銲線22〇之間的 φ 鍵結力。 根據本發明之銲線接合方法，在施壓製程時，銅製銲線 所造成之力乃作用於一外部工具之非黏性表面因此將不 會損壞接墊之結構》再者，相較於先前技術，本發明之銲 線接合結構具有較大的鍵結力，進而具有較高的可靠度口 雖然本發明已以前述實施例揭示，然其並非用以限定本 發明，任何本發明所屬技術領域中具有通常知識者，在不 脫離本發明之精神和範圍内，當可作各種之更動與修改。 ❹因此本發明之保護範®當視後附之巾請專利範圍所 為準。 【圖式簡單說明】 第1圖為先前技術之銲線接合方法之剖面示意圖。 第2至4圖為先前技術之銅製銲線接合方法之剖面示 圖。 °不意 第5至8圖為本發明之第一實施例之銅製銲線接合方法 之剖面示意圖。 α 01346-TW/ASE2135 10 201010819 第9a及9b至13圖為本發明之第二實施例之銅製銲線 接合方法之剖面示意圖。 【主要元件符號說明】The crucible 224 is in contact with the non-adhesive surface 25 of the outer tool 252 and is pressed to form the non-spherical block portion 224 as shown in Fig. 1. The non-spherical block portion 22 has a flat or rough bottom surface 226 as shown in the figure. Alternatively, by means of a nip process, the non-spherical block 4 224 is clamped in the left-right direction (as indicated by the arrow) to form another non-spherical block portion 224, as shown in FIG. . The non-spherical block portion 224 has two or four flat sides 228, as shown in the first figure. Referring to Fig. 12, an intermediate material 24 can be covered by a portion of the block portion 224 by a sticking process. For example, first, the intermediate material 240 can be in a powder solid or liquid form. Placed in a container 242. Then, the block portion 224 is inserted into the container 242 to adhere the powder solid or liquid type intermediate material 240 to the block portion 224 so as to cover a portion of the block portion 224. Preferably, the area of the block portion 224 covered by the intermediate material 240 is greater than 3% of the entire area of the block portion 224. Referring to FIG. 13, the block portion 224 can be rotated by a vibration process. The intermediate material 240 is bonded to the intermediate material 24 while the intermediate material 24 is bonded to a pad 232 to form the wire bond structure of the present invention. In the present embodiment, the pad 232 is made of aluminum, and the intermediate material 240 is selected from the group consisting of tin (Sn), gold (Au), zinc (Ζη), platinum (pt), palladium (Pd), and manganese (Mn). ), a group consisting of magnesium (Mg), indium (In), germanium (Ge), and silver (Ag). The intermediate material 01346-TW/ASE2135 9 201010819 The amount of the intermetallic compound formed between the material 240 and the copper bonding wire 22〇 is greater than the amount of the intermetallic compound formed between the aluminum pad and the copper bonding wire, and The amount of the intermetallic compound between the intermediate material 24 and the aluminum pad 232 is greater than the amount of the intermetallic compound formed between the aluminum pad 232 and the copper bonding wire 22. Therefore, the bonding force between the intermediate material 24 and the copper bonding wire 220 is greater than the bonding force between the aluminum pad 232 and the copper bonding wire 220, and the intermediate material 240 and the aluminum pad 232 are between The bonding force is greater than the φ bonding force between the aluminum pad 232 and the copper bonding wire 22〇. According to the wire bonding method of the present invention, the force caused by the copper wire is applied to the non-stick surface of an external tool during the pressing process, so that the structure of the pad will not be damaged. Technology, the wire bonding structure of the present invention has a large bonding force, and thus has a high reliability. Although the present invention has been disclosed in the foregoing embodiments, it is not intended to limit the present invention, and any technical field to which the present invention pertains. Those having ordinary skill in the art can make various changes and modifications without departing from the spirit and scope of the invention. Therefore, the protection scope of the present invention is subject to the patent scope of the attached towel. BRIEF DESCRIPTION OF THE DRAWINGS Fig. 1 is a schematic cross-sectional view showing a prior art wire bonding method. Figures 2 through 4 are cross-sectional views of prior art copper wire bonding methods. ° is a schematic cross-sectional view showing a copper bonding wire bonding method according to a first embodiment of the present invention. α 01346-TW/ASE2135 10 201010819 FIGS. 9a and 9b to 13 are schematic cross-sectional views showing a copper bonding wire bonding method according to a second embodiment of the present invention. [Main component symbol description]
10 晶片 11 接墊 12 基板 13 接墊 14 銲線 20 銲線 22 銅線 24 銅球 32 接墊 102 打線機 120 銲線 122 線狀部 124 塊狀部 132 接墊 140 中間材料 142 容器 202 打線機 220 銲線 222 線狀部 224 塊狀部 226 底面 228 側面 232 接墊 240 中間材料 242 容器 250 表面 252 工具 254 工具 01346-TW/ASE2135 1110 wafer 11 pads 12 substrate 13 pads 14 bonding wires 20 bonding wires 22 copper wires 24 copper balls 32 pads 102 wire machines 120 bonding wires 122 linear portions 124 block portions 132 pads 140 intermediate materials 142 containers 202 wire machines 220 Wire 222 Linear 224 Block 226 Bottom 228 Side 232 Pad 240 Intermediate Material 242 Container 250 Surface 252 Tool 254 Tool 01346-TW/ASE2135 11