TW201028287A - Metal clad body, circuit board and electronic part - Google Patents

Abstract

Provided are a metal clad body, circuit board and electronic part with which there is a reduction in thermal strain caused by the soldering heat when a semiconductor element is fitted to a circuit board formed by removing conductors by etching, and connection reliability is improved. The metal clad body has a film base and a metal layer comprising copper (Cu) or copper alloy (Cu alloy), and the thermal strain caused by the soldering heat when a semiconductor element is fitted to a circuit board can be reduced by using a metal clad body expanded by from 0.05 to 0.4% in the planar direction with heat treatment following removal of the metal layer by etching. Highly reliable circuit boards and electronic parts can be produced using such a metal clad body.

Description

201028287 VI. Description of the Invention: TECHNICAL FIELD OF THE INVENTION The present invention relates to a metal facing laminate, a circuit substrate, and an electronic component. In particular, it is possible to reduce the thermal deformation of the conductor by the engraving of the conductor and the mounting of the semiconductor element on the formed circuit board, and to improve the connection reliability, the metal sheath laminate, the circuit board, and the electron Components.先前 [Prior Art] In recent years, a method called COF (Chip On Film) in which a semiconductor wafer is directly mounted on a thin film wiring board has been used. In such a mounting form, the substrate connection method of the 1C driver of the liquid crystal screen is often used. However, due to the miniaturization of the signal wiring and the enlargement of the semiconductor wafer, the thermal distortion generated during mounting becomes large, and the connection reliability of the semiconductor wafer and the substrate is increased. It becomes a big problem. φ For example, the thermal expansion coefficient of the germanium wafer is 3 ppm/K, and the thermal expansion coefficient of the general substrate is 16 to 6 Oppm/Κ, so when the solder is heated to fall to room temperature, the thermal deformation due to the difference in thermal expansion becomes A big problem (for example, refer to Patent Document 1). [Prior Art] [Patent Document 1] [Patent Document 1] JP-A-2007-2625 63-A Publication No. 201028287 [Problem to be Solved by the Invention] The method for reducing the thermal deformation is, for example, used. A method of a substrate having a low coefficient of thermal expansion. However, since the circuit board uses copper as a conductor, when the thermal expansion coefficient of the film substrate is reduced, there is a problem that the substrate is bent or the like due to the difference in thermal expansion coefficient (16 ppm/K) of copper. solve. The present invention has been made in view of the above problems, and an object thereof is to provide a thermal deformation which can be reduced by removing a conductor by etching and mounting a semiconductor element on a formed circuit substrate due to solder heating, and can be A metal facing laminate, a circuit board, and an electronic component that improve connection reliability. [Means for Solving the Problem] The inventors have carefully studied the above-mentioned problems. As a result, it has been found that by using a metal sheath laminate which is expanded by 0.05 to 0.4% in the plane direction during the heat treatment after the metal layer is removed by etching, it is possible to reduce the solder when the semiconductor element is mounted on the circuit board. Thermal deformation caused by heating. Further, the heat treatment is preferably a temperature of the softened film, and is a soldering when the semiconductor wafer is directly mounted on the circuit board. The invention was created by the above research results. A metal sheath laminate according to a first aspect of the present invention is a metal sheath laminate having a film substrate and a metal layer made of copper (Cu) or a copper (Cu) alloy, and is characterized by The rate of dimensional change in the planar direction of the metal facing laminate in the heat treatment after removing the metal layer to -6-201028287 by etching is 0.05 to 0.4%. In the metal sheath laminate according to the second aspect of the present invention, the linear expansion coefficient of the film substrate in the planar direction is 13 to 6 in the metal sheath laminate according to the first aspect of the present invention. 0ppm/K. A metal sheath laminate system according to a third aspect of the present invention, in the metal sheath laminate according to the first or second aspect of the present invention, in the thin φ film substrate and the metal layer A base metal layer is formed therebetween. According to a fourth aspect of the present invention, in a metal sheath laminate according to a third aspect of the present invention, the base metal layer is made of nickel (Ni) or a nickel alloy (Ni). Any of alloys, copper (Cu), and copper alloys (Cu alloys). A metal facing laminate system according to a fifth aspect of the present invention, wherein the film substrate is hot in any one of the first to fourth aspects of the present invention Plastic film. In the metal sheath laminate according to the fifth aspect of the present invention, the film substrate is obtained by obtaining optical anisotropy. Phase polymer, thermoplastic polyimine resin, polyetheretherketone (PEEK) resin, polyethylene terephthalate (PET) resin, polyethylene naphthalate (PEN) resin Any of the categories selected in the group. In the metal facing laminate according to any one of the first to fourth aspects of the present invention, the film substrate is composed of the metal substrate laminate according to the seventh aspect of the present invention. Non-thermoplastic polyimine resin is formed in the circuit board according to the first aspect of the present invention, which is characterized in that the metal involved in any of the first to seventh aspects of the present invention is used. The laminate is laminated to form an electrical circuit. A circuit board according to a first aspect of the present invention is characterized in that a semiconductor element is directly mounted on a circuit board according to a first aspect of the present invention. According to a second aspect of the invention, in the electronic component according to the first aspect of the invention, the electrode of the semiconductor element is connected to the circuit board by a bump. Further, in the present specification, the "dimension change rate" is such that the side where the size is increased is set to be positive, and the side where the size is decreased is set to be negative. [Effects of the Invention] According to the present invention, the dimensional change rate 〇 of the metal facing laminate in the heat treatment after the metal layer is removed by etching can be 0.05 to 0.4% (expanded by heat treatment) The metal facing laminate ' is reduced in thermal deformation due to solder heating when the semiconductor component is mounted on the circuit board. Therefore, by using such a metal facing laminate body, a circuit board and electronic components having high reliability can be produced. [Embodiment] Hereinafter, one embodiment of the present invention will be described with reference to the drawings. Further, the embodiments described below are intended to illustrate the scope of the invention not limited to [S } -8- 201028287. Therefore, those skilled in the art may adopt an embodiment in which the elements or all of the elements are replaced by equivalent elements, but such embodiments are also included in the scope of the present invention. First, a metal facing laminate to which the present invention is applicable will be described. Fig. 1 is a cross-sectional view showing a metal sheath laminate according to a first embodiment of the present invention. As shown in Fig. 1, the metal Φ sheath laminate 10 according to the first embodiment of the present invention has a film substrate 11 and a metal layer 12 formed on the surface 1 la of the film substrate 11. The metal facing laminate 10 of the present embodiment has the following features. The metal facing laminate 10 has a dimensional change ratio in the planar direction of the metal facing laminate 10 in the heat treatment after etching and removing at least a part of the metal layer 12 is 0.05 to 0.4%. Further, the linear expansion coefficient of the film substrate 11 in the planar direction is 13 to 60 ppm/K. φ By using the metal facing laminate 10 of the present invention having the above characteristics, it is possible to reduce the thermal deformation caused by the heating of the solder when the semiconductor element is mounted on the circuit board. Further, by using such a metal sheath laminate 10, a circuit board and electronic components having high reliability can be produced. Next, a metal facing laminate according to another embodiment of the present invention will be described. Fig. 2 is a cross-sectional view showing a metal sheath laminate according to a second embodiment of the present invention. As shown in Fig. 2, the metal facing laminate 20 according to the second embodiment of the present invention has a film substrate 11 and is formed on each of the surfaces 11a and 11b of the film substrate 11 by -9-201028287. Metal layer 12 and metal layer 12'. The metal facing laminate 20 and the metal facing laminate 10 are different in point. The metal facing laminate 10 is a two-layer structure in which the film substrate 11 and the metal layer 12 are laminated in this order. The surface laminate 20 has a three-layer structure in which the metal layer 12' and the film substrate 11 and the metal layer 12 are laminated in this order. Further, the metal sheath laminate 20 according to the second embodiment of the present invention has the same features and effects as those of the metal sheath laminate 10. Fig. 3 is a cross-sectional view showing a metal sheath laminate according to a third embodiment of the present invention. As shown in Fig. 3, the metal facing laminate 30 according to the third embodiment of the present invention has a film substrate 11 and a base metal layer 13 formed on the surface 11a of the film substrate 11. And a metal layer 12 formed on the face 13a of the base metal layer 13. The metal facing laminate 30 and the metal facing laminate 10 are different in point. The metal facing laminate 10 is a two-layer structure in which the film substrate 11 and the metal layer 12 are laminated in this order. The surface laminate 30 has a three-layer structure in which the film substrate 11 and the base metal layer 13 and the metal layer 12 are laminated in this order. Further, the metal facing laminate 30 according to the third embodiment of the present invention has the same features and effects as the above-described metal facing laminate 10. Further, in FIG. 3, although the base metal layer 13 is formed only on one surface of the film substrate 11, and then the metal layer 12 is formed on the base metal layer 13, even if it is separately on the film substrate 11, A base metal layer 13 is formed on both sides, and then a metal layer 12' is formed on each of the base metal layers 13 in accordance with the order of the metal layer 12 and the base metal layer 13 and the film substrate 11 and the base metal layer 13 and the metal layer 12. The five-layer structure of the layer is also possible. 201028287 Next, a metal layer, a base metal layer, and a film substrate to which the metal sheath laminate of the present invention can be applied will be described. The metal layers 12, 12' to which the metal facing laminates 10, 20, 30 of the present invention can be applied are composed of copper (Cu) or a copper alloy (Cu alloy). Further, as the base metal layer 13 to which the metal sheath laminate 30 of the present invention is applicable, any of nickel (Ni), nickel alloy (Ni alloy), copper (Cu), and copper alloy (Cu alloy) is used. One is better. Further, the thickness of the base φ metal layer 13 is preferably in the range of 0.05 to 0.5 μm. Although the flexible circuit substrate is made of a non-thermoplastic polyimide substrate having excellent heat resistance, the film substrate 11 to which the metal sheath laminates 10, 20, and 30 of the present invention can be applied is used at a temperature. A method of thermally plasticizing the resin in which the higher flexible circuit substrate is easily softened is preferred. This is because copper is etched. Because heat is easy to cause expansion. Specifically, a liquid crystal polymer film, polyetheretherketone (PEEK), a thermoplastic polyimide film, a polyester film, or the like can be applied. Further, in the polyester film, although the heat resistance is relatively low, polyethylene naphthalate (PEN) and polyethylene terephthalate (PET) can be accommodated. When performing actual Sn and SnAg welding, liquid crystal polyacetate, PEEK, and thermoplastic polyimine have high heat resistance. Next, a metal sheath laminate 30 will be described as an example of a mechanism in which a circuit board (wiring board) to which the metal sheath laminate of the present invention is applied is expanded by heat treatment after etching. The metal facing laminate 30 was produced by a method in which a metal was directly electroplated on the film substrate 11 without using an adhesive. At this time, stress is left on the plating film residue -11 - 201028287, and the metal sheath laminate 30 which has been contracted by a predetermined amount in the plane direction is produced by the subsequent heat treatment. In other words, when the underlying metal layer 13 is formed by electroless plating, a film is formed by plating solution in which the electroless plating film is subjected to tensile stress and plating conditions. Next, the film is softened by heating to the softening temperature of the film, and the metal facing laminate 30 is shrunk in the planar direction by the stress of the plating film. At the time of fabricating the wiring substrate, the stress of the plating film is removed by removing a portion of the metal layer 12 by etching. Therefore, the amount of shrinkage of the film substrate 11 is liberated by reheating. That is, the metal facing laminate 30 which is expanded when the solder is heated can be obtained. First, a method of manufacturing a metal facing laminate to which the present invention is applicable will be described. Here, a method of directly plating a metal onto the film substrate 11 to form the metal facing laminate 30 will be described as an example. First, a roughening treatment (surface roughening treatment) is performed on the surface of the film substrate before plating. Next, a base layer (base metal layer or base plating layer) 13 for forming a metal layer by electroless plating (formation treatment of the underlying metal layer @) is performed. At the time of forming the underlying gold layer 13, electroplating is performed in such a manner that the stress of the plating film becomes tensile stress. To form the base metal layer 13 holding the tensile stress, the pH of the plating bath is from weakly acidic to neutral, and it is suitable for an electroless nickel-phosphorus plating solution which is precipitated at a high temperature of 60 ° C or higher. Further, the phosphorus film having a phosphorus concentration suitable for precipitation is a low concentration of phosphorus of 5 % or less, and a concentration of a phosphorus film of about 5 to 10%. The stress of the plating film (here, the base metal layer 13) is judged by tensile stress or compressive stress, and only one side of the film substrate 11 may be subjected to electro--12-201028287 plating, and the metal sheath after plating may be viewed. Judging by the direction of the bend of the layer. That is, when the plating film is placed on the upper side, if it is in a concave shape, the plating film indicates tensile stress, and if it is convex, the plating film indicates compressive stress. According to this, the plating film is contracted by the film substrate η, so that in the subsequent heat treatment, when the film substrate is softened, the metal sheath laminate 30 shrinks in the planar direction due to the stress of the plating film. Therefore, the film substrate 11 is softened by the heat treatment by the selection of the plating solution and the plating conditions, and the metal substrate laminate 3 which has been previously shrunk in the planar direction can be produced. The base metal layer 13 is deposited on the surface of the film substrate 11 in a thickness of 0.05 to 0.5 μm using an electroless nickel-phosphorus plating solution, an electroless copper plating solution or the like as a substrate for the surface of the film substrate 11. Next, heat treatment (heat treatment) is performed. Here, the heat treatment is preferably performed in a state where the metal sheath laminate 30 can be loaded with tension in such a manner as to maintain a flat shape, or in order to prevent significant deformation from being performed in a state where the φ state of the superposed film can be maintained. That is, it is preferable to perform heating by superimposing a plurality of films on a flat support plate, or performing heating in a state of being wound into a roll. Alternatively, the metal facing laminate 30 may be subjected to continuous heating even if the flat surface of the metal facing laminate 30 is maintained in a uniform shape from the heating to the cooling of the metal facing laminate 30. By the softening of the heat-treated film, the metal facing laminate 30 shrinks in the planar direction in accordance with the stress of the plating film. The larger the amount of shrinkage, the larger the amount of expansion of the solder after the copper is saturated. Finally, on the substrate plating, an electroplated copper is used to form a metal layer 12 of a thickness of 1 μm to 20 -13 to 201028287 μm as a conductor (formation treatment of the upper metal layer). A metal facing laminate 30 is produced. In the above method of fabricating the metal facing laminate 30, after the underlying metal layer 13 is formed, heat treatment is performed to finally form the upper metal layer 12, but even after the underlying metal layer 13 is formed, an upper metal layer is formed. 12, the final implementation of heat treatment is also possible. When the amount of shrinkage is set to be large, it is preferable to perform heat treatment after forming only the underlying metal layer 13. Only the side of the electroless plating film has a large tensile stress. Next, a circuit board and an electronic component to which the present invention is applicable will be described. Fig. 4 is a cross-sectional view showing a circuit board according to an embodiment of the present invention. Here, a circuit board in which a circuit is formed using the metal facing laminate 10 shown in Fig. 1 will be described as an example. As shown in Fig. 4, the circuit board 40 has a film substrate 11 and a circuit metal layer 15 which is laminated on the surface 11a of the film substrate 11 to form an electric circuit. In the method of forming the circuit metal layer 15 of the circuit board 40, the metal of the metal sheath laminate 10 shown in FIG. 1 is removed by etching, for example, by a subtractive method to form a desired wiring pattern. The metal portion of layer 12 is not required to form a circuit metal layer 15 having the desired wiring pattern. Fig. 5 is a cross-sectional view showing an electronic component according to an embodiment of the present invention. Here, an electronic component using the circuit board 40 shown in Fig. 4 will be described as an example. As shown in FIG. 5, the electronic component 50 is coated with a solder resist 17 on the surface of the circuit board 4 on the surface of the circuit board 4 shown in FIG. 4, and the circuit is connected to the circuit board 40 by the bump 18. The metal layer 15 and the electrodes of the semiconductor element 16. By using the metal facing laminate 10' to which the above-described present invention can be applied, thermal deformation due to solder heating at the time of mounting the semiconductor element 16 on the circuit board 40 can be reduced. Therefore, the circuit board 40 and the electronic component 50 having high reliability can be produced. Next, preferred embodiments of the present invention will be described. Here, the measurement result of the dimensional change rate (expansion ratio) in the planar direction of the metal facing laminate of the present invention can be applied to the heat treatment after the copper etching according to the φ, and the use of the metal laminate to which the present invention is applicable An example of the connection reliability of the circuit board and the semiconductor wafer will be described. Bian Mingzi said that the composition of the high-prepared form is 11}, and the material base is thinner than the thin film and the various examples are applied to light the film to make a thin film. The polycondensation is applied to the liquid crystal solution (( Μ φ. Here, in the case of a polymer film (liquid crystal polymer film), the case of VecsterCT manufactured using KURARA) is described. 50 μm thickness. First, the polymer film is immersed in a potassium hydroxide solution at 80 ° C for 15 to 30 minutes to dissolve the surface to form irregularities. Then, according to the modifier treatment, the nickel alloy Each of the treatments of the electroless plating treatment, the heat treatment, and the copper plating treatment is applied to produce a metal sheath laminate 30 (film metal sheath laminate) to which the present invention is applicable. The modifier treatment is performed by OPC- -15- 201028287 3 50 modified by Okuno Pharmaceutical Co., Ltd. The surface of the polymer film is washed by the OPC-80 catalyst of Okuno Pharmaceutical Co., Ltd. as a palladium-containing material. Catalyst imparting liquid, accelerated with OPC-500 As an activator. Nickel alloy electroless ore processing is performed on both sides of the film by nickel-phosphorus plating. For the commercially available nickel-phosphorus plating solution, TOP Nicoron made by Okuno Pharmaceutical Co., Ltd. LPH-LF. The film stress changes the ratio of bath temperature, pH, hypophosphorous acid and metallic nickel to produce a thin film metal facing laminate 30 composed of different base plating films (base metal layer 13) (from the embodiment) 1 to 10 of the embodiment 10). The pH is set to a range of 5.6 to 6.3, and a base plating layer (base metal layer 13) having a thickness of 0.1 μm is formed on both sides. The stress of the plating film (base metal layer 13) is determined only by The single-sided electroplating is performed, and the bending caused by the plating is observed to determine the tensile stress or the compressive stress. Further, when the plating film side is concave after the plating, the tensile stress is judged to be a convex stress. It is judged to be a compressive stress. In the heat treatment, the film metal face laminate is placed in a heat treatment bath, and the heat treatment temperature is maintained at 200 ° C to 250 ° C for 10 minutes. The copper plating treatment is based on the thickness of the conductor (the thickness of the metal layer 12) Copper (metal layer 12) is formed in a manner of 8 micrometers. The copper electro-mineral liquid is used as follows. Further, CU-BRITE TH-RIII manufactured using 荏原优吉莱特(股) is used as an additive. And, in all the examples, A conductor (metal layer 12) is formed on both sides.

Copper sulfate 120g/L sulfuric acid

150 g/L 201028287 Concentrated hydrochloric acid 0.125 mL/L (as chloride ion) Further, Example 9 and Example 10 were subjected to copper plating and then dried at 80 ° C for 30 minutes, and then heat treatment at 200 ° C or higher was performed. At this time, the determination of the stress of the plating film was as follows. The unevenness in the state in which the conductor was formed only on one side was observed, and the tensile stress or the compressive stress was judged. Further, in Comparative Example 1 to Comparative Example 6, the same film substrate 11 as that of Example 1 to Example 10 was used, and the surface was also roughened by an alkali solution. @ In Comparative Example 1, the electroless plating solution used TOP Nicoron LPH-LF. Further, the pH was set to 6.9 to form a nickel-phosphorus base plating layer having a thickness of 0.1 μm. The subsequent heat treatment was performed by setting the heat treatment temperature to 160 t for 10 minutes. Thereafter, the copper plating treatment formed copper in such a manner that the conductor thickness became 8 μm. In Comparative Example 2, the electroless plating solution used OMNI-SHIELD 1 5 80 manufactured by Rohm and Haas Company of the United States. The pH was set to 9 to form a nickel-phosphorus base plating layer having a thickness of 0.1 μm. The subsequent heat φ system was performed by setting the heat treatment temperature to 230 ° C for 10 minutes. Thereafter, copper plating was performed to form copper so that the conductor thickness became 8 μm. In Comparative Example 3, the electroless plating solution was OMNI-SHIELD 1 580 manufactured by Rohm and Haas. The pH was set to 9 to form a nickel-phosphorus film having a thickness of 0.1 μm. Thereafter, after performing drying at 80 ° C for 30 minutes, copper plating was performed, followed by heat treatment. In Comparative Example 4 to Comparative Example 6, the electroless plating solution was TOP Nicoron NAC manufactured by Okuno Pharmaceutical Co., Ltd. The pH was set to 4.6 to form a nickel-phosphorus base plating layer having a thickness of 1 μm. In the subsequent heat treatment, the heat treatment temperature of -17-201028287 was 240 ° C in Comparative Example 4, 250 ° C in Comparative Example 5, and 260 ° C in Comparative Example 6, and 10 minutes each. . Thereafter, the copper plating treatment was performed to form copper so that the conductor thickness became 8 μm. With respect to the film metal sheath laminates of Examples 1 to 1 and Comparative Examples 1 to 6 produced under the above-described conditions, after the conductors were removed, the heat generation was measured by the following method. The dimensional change rate (expansion ratio) in the plane direction. The rate of change in the plane direction was obtained by a method similar to the measurement of the dimensional stability described in IPC-TM-650 2.2.4. A scribe line is formed at the four corners of the 270 mm x 290 mm film metal facing laminate, and four evaluation points A, B, C, and D are prepared, and the evaluation point distance between AB, BC, CD, and DA is measured to be regarded as Initially. Next, all the metals in the portion other than the evaluation point region are removed by etching. Chloride is used for uranium engraving. Thereafter, heat treatment was performed for 1 minute under the assumption that the solder heating temperature was 240 °C. In the heat treatment, since the hot air of the high temperature bath does not affect the film, the film is placed in a metal box and heat treatment is performed under no load. After the heat treatment, the distance between the evaluation points of AB, BC, CD, and DA was measured again, and the change from the initial enthalpy was determined, and the change in the longitudinal direction and the width direction of the film metal sheath laminate was determined. The dimensional change rate (expansion ratio) of the average plane direction of the quantity. Table 1 shows the measurement results of the dimensional change rate (expansion ratio) in the plane direction due to the heat treatment after copper etching. -18- 201028287 [1® Expansion ratio (%) 0.38 0.32 0.29 0.27 0.24 0.19 0.15 0.11 0.09 0.06 0.04 - 0.02 rH o 0.41 0.44 0.48 -R ^ nm 纳米 | tf w Tensile tensile stretching Tensile tensile stretching Tensile tensile stretching Compression Tensile stretching Tensile heat treatment temperature (°C 250 Ο Ο m <N Ο iri (N Ο (N Ο ΓΛ CN 240 220 240 Ο <N -1 230 230 240 Ο <N 260 Process Engineering I_ 鹪ϋ 1 劲力 m &iRn> t 鹪 invite Hi k electroless shovel - heat treatment - copper plating 鹪 ipr Π 57 drops mil persuasion η & iwVn fm 衅魃壊鹪iDinfl ipr Π57 drops a tnu persuade η sense tRn> m ίρΙΓ drive m electroless plating - heat treatment - copper Electroplating electroless plating ^ heat treatment - copper electroplating electroless plating heat treatment θ copper electroplating electroless plating - heat treatment · copper electroplating mil ankle m m Πο7 t t 鹪m 璀 璀 electroless plating - copper plating - heat treatment electroless mine - Heat treatment - copper plating 鹪iUm Fl ipr 丄ffin mmt 鹪_ Invitation mil wm 灵 TWK 鹪 mm mm 缄 缄 无 无 无 无 热处理 热处理 热处理 热处理 热处理 热处理 热处理 热处理 热处理 热处理 热处理 热处理 热处理 无 无 无 无 无 无 无 无 无 无 无 无 无 无 无 无 无 无 无 无 无 无 无 无 无 无 无 无 无In mv〇\ό vo Ο 0\ ^0 mm vd Os VO OS Os VO rj- inch ' I electroless plating solution! TOP Nicoron LPH-LF TOP Nicoron LPH-LF TOP Nicoron LPH-LF TOP Nicoron LPH-LF TOP Nicoron LPH-LF TOP Nicoron LPH-LF TOP Nicoron LPH-LF TOP Nicoron LPH-LF TOP Nicoron LPH-LF TOP Nicoron LPH-LF TOP Nicoron LPH-LF OMNI-SHIELD1580 OMNI-SHIELD 1580 TOP Nicoron NAC TOP Nicoron NAC TOP Nicoron NAC Implementation Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 Example 10 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 -19- 201028287 As shown in Table 1, the dimensions of the plane directions of Examples 1 to 10 are changed by a rate of expansion (expansion ratio 15) of 0.06 to 0.38%. Further, the dimensional change ratio (expansion ratio) in the plane direction of Comparative Example 1 to Comparative Example 3 was -0.1 to 0.04%. Further, the dimensional change ratio (expansion ratio) in the plane direction of Comparative Example 4 to Comparative Example 6 was 0.41 to 0.48%. Next, since the connection reliability with the substrate of the semiconductor wafer was tested, a COF substrate was produced and a temperature cycle test was performed. A circuit board on which metal was removed by etching was produced, and an electronic component was produced by connecting to a TEG wafer using a flip chip bonding apparatus. Here, a single-sided pattern was produced by using the film-metal enamel laminate of the double-sided substrates produced in Examples 1 to 10 and Comparative Examples 1 to 6. In the case of the TEG wafer, the Hitachi ultra-LSI system uses JTEG Phase 6_50 to fabricate a wiring board suitable for this. Moreover, the specifications of JTEG Phase6_50 are as follows: 晶片 Wafer size: 16mmxl5.lmmxl5.lmm

Pad spacing: 50 microns H Number of pads: 479 pad bump size: 30 micron x lOO micron bumps: gold plating height 10 microns in order to make the circuit substrate, after subtracting the film protective layer laminate, by subtracting the method Displacement plating causes Sn plating to deposit a thickness of 0.5 microns on the copper surface. Thereafter, a solder resist is applied to form a circuit board. The connection between the circuit substrate and the wafer is performed by using a flip chip bonder to perform positioning of the bumps of the wafer and the circuit substrate, and heating to a temperature above the dissolution temperature of Sn -20-201028287 to perform bonding of the wafer and the circuit substrate. A temperature cycle test was performed as a reliability test. As a temperature cycling test condition, after repeating at -55 ° C for 10 minutes, the temperature was raised to 125 ° C for 10 minutes while the temperature was lowered to -55 ° C. The connection resistance of the wafer and the circuit board was measured every 1 〇〇 cycle as a connection resistance, and it was considered to be broken when the initial resistance was increased by 20%. Tables 2 and 6 show the number of cycles until the break was measured by the temperature cycle test.

m -21 - 201028287

[CNS cycle number (times) 1100 1900 2400 2600 2900 2800 2500 2100 1700 1100 900 600 400 800 650 450 Expansion rate (%) 0-38 0.32 0.29 0.27 0.24 0.19 0.15 0.11 0.09 0.06 0.04 -0.02 η 〇0.41 0.44 0.48 Goose • NH 鲣 鹪闼 w li w Tensile tensile stretching Tensile stretching stretching stretching stretching stretching compression stretching stretching t: stretching heat treatment temperature CC) 250 1_ ... 240 230 250 〇 230 240 220 240 200 230 230 240 Ο <Ν 260 treatment engineering electroless plating - heat treatment a copper plating m _ Πρ7 box t mil ffil m m 峨毖Μ ΙρΙΓ m 鹪 a mi \ foot m 鹪ϋ 毖 fine ipr m Electroless plating - heat treatment - copper plating m ΤΤΞΡ mil mil ffil more m invites Iff m electroless plating - heat treatment - copper electric 锼鹪 | i Π ρ7 box t tTTt 1 foot 鹪毖 鹪毖 ipr m electroless plating -> Heat treatment - copper electroplating electroless electrowinning - copper electroplating - heat treatment electroless plating - > copper electric shovel - heat treatment electroless electrolysis -> heat treatment - copper electroplating electroless plating - heat treatment - copper plating mi 1 W η 1RH, t 鹪ilii Ml Ιρ!Γ 鹪衅 壊 壊 壊 电解 — — 热处理 热处理 热处理 热处理 热处理 热处理 热处理 热处理 OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS OS ^0 〇\ — Inch · Electroless plating solution TOP Nicoron LPH-LF TOP Nicoron LPH-LF TOP Nicoron LPH-LF TOP Nicoron LPH-LF TOP Nicoron LPH-LF TOP Nicoron LPH-LF TOP Nicoron LPH-LF TOP Nicoron LPH- LF TOP Nicoron LPH-LF TOP Nicoron LPH-LF TOP Nicoron LPH-LF OMNI-SHIELD 15 80 OMNI-SHIELD1580 TOP Nicoron NAC TOP Nicoron NAC TOP Nicoron NAC Example 1 Example 2 Example 3 Example 4 Example 5 Example 6 Example 7 Example 8 Example 9 Example 10 Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Comparative Example 5 Comparative Example 6 -22- 201028287 As shown in Table 2 and Figure 6, it is known that copper plating Then, in the example 1 to the first embodiment, the dimensional change rate (expansion ratio) in the plane direction after the heat treatment at a heating temperature of 240 ° C for 1 minute was 〇 〇 5% to 0.4%, to break The number of cycles until then is large. In other words, in Example 1 to Example 10 in which the dimensional change ratio (expansion ratio) in the planar direction after the heating treatment at a heating temperature of 240 ° C for 1 minute was 0.05% to 0.4%, it was found that high connection reliability was exhibited in Examples 1 to 10. . In addition, in Example 3 to Example 8, in which the dimensional change ratio (expansion ratio) in the plane direction after the Φ heat treatment at a heating temperature of 240 ° C for 1 minute was 0. 1% to 0.3%, it was found that High connection reliability. Further, it is understood that Comparative Example 1 to Comparative Example 3 in which the dimensional change ratio (expansion ratio) in the planar direction after the heat treatment at a heating temperature of 240 ° C for 1 minute was less than 0.05%, and the heating temperature of 240 ° C was performed for 1 minute. In Comparative Example 4 to Comparative Example 6 in which the dimensional change rate (expansion ratio) in the planar direction after the heat treatment was more than 0.4%, the number of cycles until the breakage was small, and the connection reliability was low. φ Next, the case of using PEEK, thermoplastic polyimine, PET, PEN, and non-thermoplastic polyimine as other film substrates will be described. (Examples and Comparative Examples of PEEK) A case where PEEK is used as a film substrate will be described. Here, the case where IBUKI made using Mitsubishi Resin Co., Ltd. is used as PEEK will be described. Also, the film thickness was 50 μm thick. First, the PEEK is immersed in a hydrogen -23-201028287 of a normal temperature of 80 ° C for 15 to 30 minutes to form a concave and convex surface. Then, each treatment was carried out in the order of the modifier treatment, the electroless plating treatment of the nickel alloy, the heat treatment, and the electroplating treatment of copper to produce a film metal sheath laminate. Using the electric shovel liquid shown in Table 3, a base plating layer having a thickness of 0.1 μm was formed, and heat treatment was performed for 1 〇 minutes using the heat treatment temperature shown in Table 3, and copper plating treatment was performed to form copper in such a manner that the conductor thickness became 8 μm. . Also, in all embodiments, the conductors are formed on both sides. The film metal sheath laminates of Examples 11 to 20 and Comparative Examples 7 to 12 produced under the above-described conditions were the same as those of the polymer film (liquid crystal polymer film). The dimensional change rate (expansion ratio) in the plane direction due to heating after the conductor was removed was measured. Further, since the test was reliable in connection with the substrate of the semiconductor wafer, a COF substrate was produced and a temperature cycle test was performed. Fig. 3 and Fig. 7 show the reason why the test is to measure the flatness of the ring by the rate of the expansion. Borrowing fruit to the end of the knot and measuring to measure the number of hot knots of the fruit ring after the test of the hungry } stop copper rate according to the expansion -24- 201028287

Number of cycles (times) 〇in o 卜o 2100 2200 2300 2000 Ο α\ 〇 Ο Ό Ο Ο mo Ο Ο <Ν ^Η ο 冢ο ο Expansion rate (%) 〇 〇 as as CN 〇 (N c5 1- H (N 〇in o Ο Ο o Ο sooo -0.02 inch Ο JO ο ο § m N m 鲣sm 0 Tensile tensile stretching stretching stretching stretching stretching stretching stretching stretching tensile drawing Stretching and stretching heat treatment temperature ΓΟ , ooo (N o (N CS ο ο CN 1-Η § ο ^-Η s Ο (Ν ο < Ν ο ο (Ν processing project 鹪 1 m iliiml Ipr a ^ 1 ΐ ΐιιπτί TO 1 η 黑舔1Rrt, m 'Ο σ\ — Electroless plating solution TOPNicoronLPH-LF I _I OMNI-SHIELD 1580 I TOPNicoronNAC Manufacturer name Mitsubishi resin Mitsubishi resin Mitsubishi resin Mitsubishi resin Mitsubishi resin Mitsubishi resin Mitsubishi resin Mitsubishi resin Mitsubishi resin Mitsubishi Resin Mitsubishi resin Mitsubishi resin Mitsubishi resin Mitsubishi resin Mitsubishi resin Mitsubishi resin 1 Product name IBUKI IBUKI IBUKI IBUKI IBUKI IBUKI IBUKI IBUKI IBUKI IBUKI IBUKI IBUKI IBUKI IBUKI IBUKI IBUKI 11 PEEK PEEK ω ω CU ω Pi u PQ ω CU m ω pu ω Cu w ω CU ω ω CU Ph W w pu ω ω ω Pn Dh ω ω ω w pu 实施 Example 11 Example 12 Example 13 Example M Example 15 Example 16 Example 实施 Example 18 Example 19 Example 20 Comparative Example 7 Comparative Example 8 Comparative Example 9 Comparative Example 10 Comparative Example Π Comparative Example 12 -25- 201028287 As shown in Tables 3 and 7, it is understood that after the copper plating, the surface after the heat treatment at a heating temperature of 240 ° C for 1 minute is known. In the eleventh embodiment to the twenty-second embodiment, the dimensional change rate (expansion ratio) of the direction was 0.05% to 0.4%, and the number of cycles until the breakage was large. That is, it was found that heating at a heating temperature of 240 ° C for 1 minute was performed. In the embodiment 11 to the embodiment 20 in which the dimensional change rate (expansion ratio) in the planar direction after the treatment is 0.05% to 0.4%, the high connection reliability is shown. Further, it is understood that after the heat treatment of the heating temperature of 240 t for 1 minute is performed Comparative Example 7 to Comparative Example 9 in which the dimensional change rate (expansion ratio) in the planar direction was less than 0.05%, and the dimensional change ratio (expansion ratio) in the planar direction after the heat treatment at the heating temperature of 240 ° C for 1 minute was performed was more than 0.4. % comparison example 10 to comparison In Example 12, it was shown that the number of cycles until the breakage was small, and the connection reliability was low. (Examples of PET and PEN and comparative examples)

The case where PET and PEN are used as a film substrate will be described. H Here, the case of using Tetoron HSL made by Teijin DuPont Film Co., Ltd. as PET is explained. Also, the film thickness was 50 μm thick. Here, the case where Te〇nex Q83 manufactured using Teijin DuPont Film Co., Ltd. is used as PEN will be described. Also, the film thickness was 50 μm thick. First, sand blasting is performed to apply a sanding layer as a roughening of the film to form irregularities on the surface of the film. Then, in accordance with the procedures of the modifier treatment, the electroless plating treatment of the nickel alloy, the heat treatment, and the copper plating treatment, each of the treatments was carried out to produce a film metal sheath laminate. Using the plating solution shown in Table 4, a base plating layer having a thickness of 0.1 μm was formed, and heat treatment was performed for 10 minutes by the heat treatment temperature shown in Table 4. The copper plating treatment was performed to form copper so that the conductor thickness became 8 μm. Also, in all embodiments, the conductors are formed on both sides. The film metal sheath laminates of Example 21 to Example 30 φ and Comparative Examples 13 to 18 produced under the above-described conditions were the same as those of the polymer film (liquid crystal polymer film). The dimensional change rate (expansion ratio) in the plane direction due to heating after the conductor was removed was measured. Furthermore, since the test was connected to the substrate of the semiconductor wafer, the COF substrate was fabricated and the temperature cycle test was performed. Here, since PET and PEN have low heat resistance, the heating after the conductor is removed in the measurement of the dimensional change rate (expansion ratio) in the planar direction is performed at 170 ° C for 1 minute at the time of PET, and at 20 minutes at PEN. (TC performs 1 minute of enthalpy heat treatment. Further, since PET and PEN films have low heat resistance, Sn electric ore and Bi plating I are executed. Further, contact with the wafer is performed by heating at about 150 °C. Fig. 4 and Fig. 8 show the measurement results of the dimensional change rate (expansion ratio) in the plane direction by the heat treatment after copper etching and the number of cycles up to the measurement by the temperature cycle test. Measurement results -27- 201028287

-28- 201028287 As shown in Tables 4 and 8, it is known that the dimensional change ratio (expansion ratio) in the plane direction after the copper plating is performed at a heating temperature of 170 r or 200 ° C for 1 minute is From 0.05% to 0.4% of Examples 21 to 30, the number of cycles until breaking was large. In other words, in Example 21 to Example 30, in which the dimensional change ratio (expansion ratio) in the plane direction after the heat treatment at 170 ° C or 200 ° C for 1 minute was performed was 0.05% to 0.4%, High connection reliability. In addition, it is known that the heating temperature 17 (the dimensional change rate (expansion ratio) in the plane direction after the heat treatment of TC is less than 0.05%, Comparative Example 1 3 to Comparative Example 15 is performed, and the heating temperature of 200 ° is performed for 1 minute). In Comparative Example 16 to Comparative Example 18 in which the dimensional change rate (expansion ratio) in the planar direction after the heat treatment of C was more than 0.4%, the number of cycles until the breakage was small, and the connection reliability was low. Examples and comparative examples of quinone imine) φ is described for the case where a thermoplastic polyimide is used as a film substrate. Here, the case of using Mitsui Chemical as a thermoplastic polyimide is described. The thickness of the film is 25 μm. First, the thermoplastic polyimide is immersed in a potassium hydroxide solution at 10 ° C for 10 to 15 minutes at 80 ° C to dissolve the surface to form irregularities. Then, according to the modifier The treatment, the electroless plating treatment of the nickel alloy, the heat treatment, and the copper plating treatment were sequentially applied to each other to produce a thin film metal sheath laminate. Using the plating solution shown in Table 5, a 0. 1 micron thick substrate plating -29- 201028287 layer, using the heat treatment temperature shown in Table 5, performing heat treatment for 10 minutes, copper plating treatment was performed in such a manner that the conductor thickness became 8 μm. And, in all the examples A conductor is formed on both sides. The film metal sheath laminates of Examples 31 to 40 and Comparative Examples 19 to 24 produced under the above-described conditions, and a polymer film (liquid crystal polymer film) In the same manner, the dimensional change rate (expansion ratio) in the plane direction due to heating after the conductor was removed was measured. @ Furthermore, since the connection reliability with the substrate of the semiconductor wafer was tested, the COF substrate was fabricated to perform a temperature cycle test. Fig. 5 and Fig. 9 show the measurement results of the dimensional change rate (expansion ratio) in the plane direction by the heat treatment after copper etching and the number of cycles up to the measurement by the temperature cycle test. Measurement results S1 -30 - 201028287 e❿ r—13⁄4 Cycle number (times) 900 1000 1- 1200 1300 1 | 1400 1300 1200 1000 00 870 700 600 Ο 7 00 600 400 Expansion ratio (%) 0.39 0.36 1- 0.33 1 1 0.28 1 1 0.25 0.20 0.15 0.11 0.08 0.06 0.43 0.48 0.50 0.02 -0.02 -0.08 ••N mm mg运mg ϋ 丨Stretching stretching drawing Stretching, Tensile, Tensile, Tensile, Tensile, Tensile, Tensile, Tensile, Compression, Heat Treatment, Temperature rc) 〇290 (N 270 260 300 (N 280 〇260 320 Ο cn cn 〇〇<N 280 treatment) Engineering I_ I- Electroless plating heat treatment - Copper plating electroless plating - Copper plating - Heat treatment Electroless plating - Heat treatment - Copper electroless electroless plating - Heat treatment - Copper electric ore m 'Ο I Electroless plating solution TOP Nicoron LPH-LF TOP Nicoron LPH-LF OMNI-SHIELD1580 1 Manufacturer name Mitsui Chemicals 1 Mitsui Chemicals Mitsui Chemicals Mitsui Chemicals Mitsui Chemicals Mitsui Chemicals Mitsui Chemicals Mitsui Chemicals Mitsui Chemicals Mitsui Chemicals Mitsui Chemicals Mitsui Chemicals Mitsui Chemicals Mitsui Chemicals Mitsui Chemicals Mitsui Chemicals Product Name I 丨AURUM AURUM AURUM AURUM AURUM AURUM AURUM AURUM AURUM AURUM AURUM AURUM AURUM AURUM AURUM AURUM Film Substrate] Thermoplastic PI Heat PI Thermoplastic PI Thermoplastic PI Thermoplastic PI Thermoplastic pi Thermoplastic PI Thermoplastic PI Thermoplastic PI Thermoplastic PI Thermoplastic PI Thermoplastic PI Thermoplastic PI Thermoplastic pi Thermoplastic PI Thermoplastic PI Example 31 Example 32 Implementation Example 33 Example 34 Example 35 Example 36 Example 37 Example 38 Example 39 Example 40 Comparative Example 19 Comparative Example 20 Comparative Example 21 Comparative Example 22 Comparative Example 23 Comparative Example 24-31 - 201028287 Table 5 and As shown in Fig. 9, it can be seen that after the copper plating, the dimensional change rate (expansion ratio) in the plane direction after the heat treatment at a heating temperature of 240 ° C for 1 minute is 0.05% to 0.4%. In Example 40, the number of cycles until breaking is large. In other words, in Example 31 to Example 40 in which the heating temperature was 24 in 1 minute (the dimensional change rate (expansion ratio) in the planar direction after the heat treatment of TC was 0.05% to 0.4%, it was found that 'high connection reliability' was expressed. In addition, it can be seen that the dimensional change rate (expansion ratio) in the plane direction after performing the heating treatment at a heating temperature of 240 ° C for 1 minute is less than 〇 〇 5% of Comparative Example 22 to Comparative Example 24, and 1 minute of execution. In Comparative Example 19 to Comparative Example 21 in which the dimensional change rate (expansion ratio) in the planar direction after the heat treatment at a heating temperature of 240 ° C was more than 0.4%, the number of cycles until the breakage was small, and the connection reliability was low. (Examples and Comparative Examples of Non-Thermoplastic Polyimine) For the case of using non-thermoplastic polyimine as a film substrate, the description will be made here. For the purpose of using Toray and DuPont (shares) Kapton 100 00 is described as a non-thermoplastic polyimine. First, the non-thermoplastic polyimine is immersed in a temperature of 80 ° C (

Normal potassium hydroxide solution for 5 to 15 minutes to form irregularities on the dissolved surface. Then, each treatment was carried out in the order of the modifier treatment, the electroless plating treatment of the nickel alloy, the heat treatment, and the copper plating treatment to produce a thin film metal sheath laminate. Using the plating solution shown in Table 6 to form a 0.1 μm thick base plating-32-201028287 layer, using the heat treatment temperature shown in Table 6 to perform the heat treatment of the 〇 〇 minute copper plating treatment with a conductor thickness of 8 μm The way to form copper. Also, in all embodiments, the conductors are formed on both sides. The film metal sheath laminates of Examples 41 to 46 and Comparative Examples 25 to 28 produced under the above-described conditions were the same as those of the polymer film (liquid crystal polymer film), and were measured. The rate of dimensional change (expansion ratio) in the plane direction due to heating after removal of the conductor. Furthermore, since the connection reliability of the test and the substrate of the semiconductor wafer was tested, a COF substrate was produced and a temperature cycle test was performed. Tables 6 and 10 show the measurement results of the dimensional change rate (expansion ratio) in the plane direction by the heat treatment after copper etching and the number of cycles up to the measurement by the temperature cycle test. result. -33- 201028287

-34- 201028287 As shown in Tables 6 and 10, it is understood that the dimensional change ratio (expansion ratio) in the plane direction after the heat treatment at a heating temperature of 240 ° C for 1 minute after copper plating is 0.05 %. In 0.4% of Examples 41 to 46, the number of cycles until breaking was large. In other words, in Example 41 to Example 46 in which the dimensional change ratio (expansion ratio) in the plane direction after the heat treatment at a heating temperature of 24 ° C for 1 minute was 0.05% to 0.4%, it was found that the table was not connected. Trustworthiness. In addition, in Comparative Example 25 to Example 88 in which the dimensional change ratio (expansion ratio) in the planar direction after the heating treatment at a heating temperature of 240 ° C for 1 minute was less than 0.05%, the number of cycles until breaking was shown. Small, the connection is low in reliability. As shown in the above Tables 1 to 6 and Figs. 6 to 10, it is understood that when the dimensional change rate (increase ratio) in the plane direction due to heating after copper etching is 0.05 to 0.4%, the connection is made. High reliability. Further, it is understood that liquid φ crystalline polyester (polymer) or PEEK is used as a film substrate to achieve high connection reliability when performing soldering of Sn or SnAg used in a usual circuit board. Further, it is also known that PET or PEN can be used when heat resistance is not required. From the above, it is known that the semiconductor substrate is directly mounted on the circuit substrate of the metal protective surface laminate which is expanded in the planar direction by the heat treatment after removing the metal layer by uranium engraving (for example, 'by the convex When the block is connected to the electrode of the circuit board and the semiconductor wafer, it is possible to manufacture an electronic component having high reliability. -35-201028287 [Brief Description of the Drawings] H1 is a cross-sectional view of a metal sheath laminate according to the first embodiment of the present invention. The second aspect of the present invention is a cross-sectional view showing a metal sheath laminate according to a second embodiment of the present invention. Fig. 3 is a cross-sectional view showing a metal sheath laminate according to a third embodiment of the present invention. The fourth embodiment is a cross-sectional view of the circuit board @ according to an embodiment of the present invention. The stomach 5 is a cross-sectional view showing an electronic component according to an embodiment of the present invention. Fig. 6 is a graph showing the connection reliability when the film substrate is a polymer film (liquid crystal polymer film). Fig. 7 is a graph showing the connection reliability when the film substrate is PEEK. Fig. 8 is a graph showing the connection reliability Θ when the film substrate is PET or PEN. Fig. 9 is a graph showing the connection reliability when the film substrate is a thermoplastic polyimide. The figure is a graph showing the connection reliability when the film substrate is a non-thermoplastic polyimide. [Description of main component symbols] 10, 20, 30: metal facing laminate] -36- 201028287

11: 12, 13 : 15 : 16 : 17 ·· 18 : 50 : Film substrate 1 2 ' ·' Metal layer Base metal layer Circuit metal layer Semiconductor conductive element Solder resist Bump Circuit board Electronic parts

Claims (1)

201028287 VII. Patent application scope: 1. A metal sheath laminate having a film substrate and a metal layer composed of copper (Cu) or a copper alloy (Cu alloy), characterized by: removing the metal by etching The dimensional change rate in the planar direction of the metal facing laminate in the heat treatment after at least a portion of the layer is 0.05 to 0.4%. 2. The metal facing laminate according to the scope of the patent application, wherein the linear expansion coefficient of the planar direction of the film substrate is 10 to 60 ppm/K ° 3. If the patent application scope is 1 or The metal sheath laminate according to the item 2, wherein the base metal layer is formed between the film substrate and the metal layer. 4. The metal facing laminate according to claim 3, wherein the base metal layer is made of nickel (Ni), nickel alloy (Ni alloy), copper (Cu), copper alloy (Cu alloy) Any of them. 5. The metal facing laminate according to any one of claims 1 to 4, wherein the film substrate is a thermoplastic film. 6. The metal sheath laminate according to claim 5, wherein the film substrate is composed of a high-38-201028287 molecule obtained from an optically anisotropic molten phase, and a thermoplastic polycondensate. Any of a group selected from the group consisting of an amine resin, a polyetheretherketone (PEEK) resin, a polyethylene terephthalate (PET) resin, and a polyethylene naphthalate (PEN) resin. 7. The metal facing laminate according to any one of claims 1 to 4, wherein the film substrate is formed of a non-thermoplastic polyimine resin. The circuit board is characterized in that the circuit is formed by using the metal sheath laminate according to any one of claims 1 to 7. An electronic component characterized in that: the semiconductor element is directly mounted on the circuit board described in claim 8 of the patent application. 10. The electronic component according to claim 9, wherein the electrode of the semiconductor element is connected to the circuit base panel by a bump. -39-