JP2007324418A - Semiconductor device, manufacturing method for solder bump connection board, and manufacturing method for semiconductor device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a board connection structure for connecting boards via solder bumps which structure prevents short circuit between the solder bumps caused by deformation of the solder bumps, and connects the boards firmly using an underfill. <P>SOLUTION: In the board connection structure, a pillarlike structure 4 made of an insulating material is disposed between the solder bumps 3 closest to each other, and a gap between the connected boards 1 and 2 is filled with the underfill 5. The deformed solder bumps 3 are blocked by the pillarlike structure 4 made of the insulating material, which prevents short circuit between the adjacent solder bumps 3. The plane of the pillarlike structure 4 and that of the solder bump 3 are separated from each other, so that the inflow of the underfill from the periphery of the structure 4 and solder bump 3 is not obstructed to allow firm connection through the underfill 5 with less voids. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a semiconductor device for connecting two substrates using solder bumps, a method for manufacturing a solder bump connection substrate suitable for such connection, and a method for manufacturing a semiconductor device using the solder bump connection substrate. The present invention relates to a semiconductor device having a substrate connection structure for preventing a short circuit between adjacent bumps due to deformation of the bump, a method for manufacturing a solder bump connection substrate used in the semiconductor device, and a method for manufacturing such a semiconductor device.

  In the field of electronic circuits, there are a wide range of substrate connection methods in which two substrates having electrodes formed on the main surface are arranged so that the electrodes on each substrate face each other and the electrodes are connected by solder bumps. in use. For example, a flip chip using solder bumps as connection electrodes of a semiconductor substrate (chip) on which a semiconductor integrated circuit is formed, a grid array package in which circuit boards mounted with a semiconductor substrate are connected by solder balls arranged in a grid array, or It is used to connect various substrates such as sub circuit substrates mounted on the main circuit substrate using solder bumps.

  Such a solder bump is formed on an electrode (lower surface) provided on the lower surface of one substrate. At the time of connection, this one board is placed on the other board, for example, the main circuit board, with the positions of the electrodes and solder bumps of the other board aligned. Next, the electrodes on one and the other substrates are connected via solder bumps by reflow or ultrasonic bonding. Thereafter, an underfill is filled between one and the other substrates and cured to strengthen the adhesion between the two substrates. At this time, a method of reducing the connection failure and stress concentration due to the uneven distribution of the load and the unevenness of the height of the solder bump at the time of connection by arranging a spacer to keep the distance between the substrates constant is also adopted. .

  However, as the degree of integration of the semiconductor integrated circuit is improved, the number of electrodes, for example, solder bumps, constituting the external terminals is increased, and the pitch between the electrodes is shortened. For this reason, in the connection method described above, when connecting by reflow or the like, the adjacent solder bumps may be deformed to contact each other and cause a short circuit. Further, in the conventional connection method described above, the spacer is provided outside the solder bump formation region, and although there is an effect of suppressing the deformation of the solder bump by the arrangement of the spacer, the short circuit with the adjacent solder bump is sufficiently performed. It is difficult to prevent.

  A method of preventing a short circuit between adjacent solder bumps using a mesh spacer is disclosed. (For example, refer to Patent Document 1).

  FIG. 13 is an explanatory diagram of a conventional substrate connection structure, and shows a substrate connection structure in which a short circuit between solder bumps is prevented using a mesh spacer. FIG. 13A is an assembly view according to a perspective view, and FIG. 13B is a vertical cross-sectional view taken along line G-G ′ in FIG.

  Referring to FIG. 13, in this method, mesh spacer 44 is inserted between the substrates to be connected, that is, between LSI 41 and electronic circuit board. At this time, the solder bumps 43 are arranged in each mesh of the mesh spacer 44. Accordingly, since each solder bump 43 is completely isolated by the mesh spacer 44, a short circuit with the adjacent solder bump 43 due to reflow can be completely prevented.

However, since the mesh spacer 44 is in contact with the LSI 41 at the top and the electronic circuit board 42 at the bottom, underfill cannot be injected from the outside of the mesh spacer 44 after connection by the solder bumps 43. For this reason, a strong adhesion method using underfill cannot be applied.
JP-A-6-232203

  As described above, the conventional board connection structure has a problem that the solder bump is deformed to contact and short-circuit with the adjacent solder bump at the time of connection or at the time of reflow in a later process. Further, even if the spacer is provided outside the solder bump formation region to suppress the deformation of the solder bump, the short circuit of the solder bump cannot be prevented.

  Furthermore, in the method of inserting a mesh spacer between the substrates and isolating each solder bump by the mesh spacer to prevent contact between the solder bumps, underfill is injected from the outside of the mesh spacer after the solder bump is connected. I can't. For this reason, there exists a problem that the firm connection structure using an underfill cannot be taken.

  The present invention relates to a substrate connection structure in which two substrates are connected using solder bumps, and a substrate connection structure that prevents a short circuit between adjacent solder bumps and provides a strong connection by underfill, and such a substrate connection. It is an object of the present invention to provide a solder bump connection substrate suitable for providing a structure and a method of manufacturing the solder bump connection substrate.

  A semiconductor device having a first configuration according to the present invention for solving the above-described problems is formed by connecting the first and second electrodes formed on the main surfaces of the first and second substrates to each other by solder bumps, In a semiconductor device in which the space between the first and second substrates is filled with an underfill, a columnar structure made of an insulator is provided between each solder bump.

  In the first configuration, a columnar structure made of an insulator is disposed between each solder bump. For this reason, even if the solder bumps are deformed when the substrate is connected, the contact with the adjacent solder bumps is hindered by the columnar structure, so that a short circuit between the solder bumps due to the deformation of the solder bumps can be avoided.

  On the other hand, the columnar structures are discretely arranged between the solder bumps. That is, small cross sections of the columnar structures are distributed between the solder bumps on the cross section of the columnar structures and the solder bumps parallel to the main surface of the substrate. For this reason, underfill can be easily injected into the gap between the first and second substrates connected by the columnar structure and the solder bumps from the periphery of the connection portion. Therefore, in the first configuration, a strong connection structure using the underfill can be formed. Even when the underfill is not completely filled between the substrates and a void straddling between the solder bumps is generated, the deformation of the solder bumps is suppressed by the columnar structure, so that a short circuit between the solder bumps is avoided.

  The columnar structure having the first structure can be formed at a height equal to the distance between the first and second substrates and function as a spacer. Thereby, the space | interval between 1st and 2nd board | substrates is hold | maintained to predetermined distance, and since an excessive deformation | transformation of a solder bump is prevented, the short circuit between solder bumps is prevented more.

  In addition, the height of the columnar structure having the first configuration can be made shorter than the interval between the first and second substrates. That is, the columnar structure is erected on the main surface of one substrate of the first or second substrate, and the tip does not reach the main surface of the other substrate facing the columnar structure. Therefore, this columnar structure does not function as a spacer. By doing so, a gap is formed between the columnar structure and the main surface of the first or second substrate. For this reason, when the underfill is injected into the gap between the first and second substrates connected by the solder bumps, the underfill can flow through the gap and therefore the underfill can be more easily performed than in the first configuration. Can be injected.

  The columnar structure having the first configuration described above preferably has a rounded cross-sectional shape so as not to prevent inflow of underfill injected from the periphery of the connection portion. From the same point of view, a plate shape having a long side in the flow direction of the underfill may be used.

  In the first configuration, the insulator columnar structure can be disposed between the solder bumps at the closest positions. By arranging in this way, the deformation of the nearest solder bump that is most likely to come into contact with the deformation of the solder bump is blocked by the columnar structure of the insulator, and the short circuit between the adjacent solder bumps is prevented.

  Moreover, the columnar structure of the insulator can be further disposed between the solder bumps at the second adjacent position. Thereby, the short circuit which deform | transforms and protrudes between nearest solder bumps and contacts a 2nd adjacent solder bump can be prevented.

  The above-described semiconductor device having the first configuration is connected to another substrate, for example, an electronic circuit substrate via solder bumps, and is firmly connected to the electronic circuit substrate by injecting underfill into the gap between the two substrates. Electronic equipment can be manufactured.

  At this time, an electrode and a columnar structure made of an insulating resin standing between the electrodes at the closest position are provided on the main surface of the first substrate, and no solder bump is provided on the main surface of the first substrate. it can. By connecting another substrate to the first substrate via a solder bump, an electronic apparatus having the semiconductor device having the first configuration described above can be manufactured. In this configuration, a normal flip chip or grid array package substrate used in a semiconductor integrated circuit can be used as another substrate.

  A solder bump connection substrate used as the first substrate or the second substrate of the semiconductor device of the present invention described above, a step of forming a plurality of electrodes on the main surface of the substrate, a step of forming solder bumps on the electrodes, Forming a photosensitive insulating resin layer on the substrate, exposing and developing, and forming a columnar structure composed of the photosensitive insulating resin layer between the electrodes at the closest positions; It can be manufactured by a method. Note that either the solder bump forming step or the columnar structure forming step may be performed first.

  According to the method for manufacturing a solder bump connecting substrate, the columnar structure can be formed by patterning by applying a photosensitive resin, exposing and developing, and thus manufacturing is easy. Further, since the height of the columnar structure is defined by the thickness of the photosensitive raw insulating resin layer applied on the substrate, the height of the columnar structure can be precisely controlled.

  Further, in the method for manufacturing a semiconductor device of the present invention, the step of forming the solder bump connection substrate having the plurality of first electrodes on the main surface described above, and the plurality of the plurality of formed on the main surface corresponding to the first electrode. Filling the main surface of the second substrate having the second electrode with solder bumps so that the first electrode and the second electrode face each other, and filling the main surface between the first and second substrates with underfill The process of carrying out.

  The semiconductor device manufactured by the method for manufacturing the semiconductor device is prevented from being short-circuited between the solder bumps, and is firmly fixed between the first and second substrates by bonding with a strong underfill.

  According to the present invention, a short circuit between solder bumps can be prevented, and a substrate connection structure using strong solder bumps in which two substrates are bonded with an underfill can be formed.

  1st Embodiment of this invention is related with the board | substrate connection structure which has arrange | positioned the columnar structure which serves as a spacer between the nearest solder bumps.

  FIG. 1 is an explanatory diagram of a substrate connection structure according to a first embodiment of the present invention. FIG. 1A shows a planar shape for representing the arrangement of solder bumps and columnar structures, FIG. 1B shows a vertical cross section along AA ′ in FIG. 1A, and FIG. The vertical cross section along BB 'of Fig.1 (a) is represented.

  With reference to FIG. 1, the substrate connection structure of the first embodiment uses an LSI chip (flip chip) for face-down bonding as the first substrate 1, and an electronic circuit substrate serving as a motherboard as the second substrate 2. The first substrate 1 is connected to the second substrate via solder bumps 3.

  On the main surface of the first substrate 1 (the lower surface of the first substrate 1 in FIG. 1B), electrodes 1a are arranged in a grid pattern at a pitch of 200 μm in both vertical and horizontal directions. An electrode 2 a is also arranged on the main surface of the second substrate 2 at a position corresponding to the electrode 1 a of the first substrate 1. The first and second substrates 1 and 2 are connected by making these corresponding electrodes 1a and 2a face each other and joining them using solder bumps.

  The solder bump may be a bump used for normal face-down bonding, and may be, for example, a ball-shaped solder bump. The height and diameter of the solder bumps are appropriately selected according to the distance between the first and second substrates 1 and 2. For example, when the distance between the first and second substrates 1 and 2 is 60 μm, ball-shaped solder bumps having a diameter of 80 μm can be used.

  Between the main surfaces of the first substrate 1 and the second substrate 2, there are columnar structures 4 made of insulating resin whose both ends are in contact with the main surfaces of the first substrate and the second substrate 2, for example, polygonal columns, cylinders, and elliptical columns. The columnar structure 4 is provided as a spacer, and the distance between the main surfaces of the first substrate and the second substrate 2 is maintained at 60 μm, for example.

  The size of the cross section of the columnar structure 4 must be large enough to have strength as a spacer and not to prevent the underfill 5 from being injected. From this point of view, for example, the columnar structure 4 can be made of a cylinder having a diameter of 40 μm. Moreover, the material of the columnar structure 4 should just be an insulator which can maintain the intensity | strength as a spacer, for example, can use insulating resin.

  This columnar structure 4 is arranged at an intermediate position between adjacent solder bumps 3 at the closest position, for example, at the midpoint of a straight line connecting the centers of the closest solder bumps 3. Other arrangement positions of the columnar structure 4 will be described later.

  Between the main surfaces of the first substrate 1 and the second substrate 2, the underfill 5 is filled and hardened, whereby the connection between the substrates 1 and 2 is strengthened. The underfill 5 is injected from the periphery of the substrate 1 and cured after the substrates 1 and 2 are connected by the solder bumps 3.

  In the first embodiment, the solder bumps 3 and the columnar structures 4 may be fixed to the first substrate 1 or the second substrate 2 in advance, and the columnar structures 4 prepared in advance may be connected. In some cases, it may be arranged on the substrates 1 and 2. Furthermore, one of the solder bump 3 and the columnar structure 4 can be fixed to one of the substrates 1 and 2 and the other can be fixed to the other of the substrates 1 and 2.

  FIG. 2 is a sectional view of a modified example of the first embodiment of the present invention, and shows a section of this modified example corresponding to the vertical section of FIG.

  Referring to FIG. 2 (a), in this modification, the columnar structure 4a is provided on the main surface of the first substrate 1, and the tip of the columnar structure 4a (the lower end of FIG. 2 (a)) is opposed. 2 Does not reach the main surface of the substrate 2. For this reason, there is a gap between the tip of the columnar structure 4 a and the main surface of the second substrate 2.

  In this modification, since there is a gap between the columnar structure 4a and the second substrate 2, when an underfill is injected between the first and second substrates 1 and 2 from the outer periphery of the first substrate 1, The turbulence of the fill flow is small and the formation of voids is small. In this modification, since the columnar structure 4 does not function as a spacer, the interval between the first and second substrates 1 and 2 is maintained exclusively by the solder bumps 3.

  With reference to FIG. 2B, the columnar structure 4 a of the modification shown in FIG. 2A can be provided on the main surface of the second substrate 2. By doing in this way, the short circuit by the deformation | transformation of the solder bump 3 can be more effectively suppressed than the modification shown to Fig.2 (a) so that it may mention later. The tip of the columnar structure 4a (the upper end of FIG. 2A) does not reach the main surface of the first substrate 2 that is opposed, and a gap is formed between the tip of the columnar structure 4a and the main surface of the first substrate 1. Have. Even in this modified example, the flow of the underfill 5 is less disturbed and voids are less generated.

  The columnar structure 4a preferably has a height at which the deformation of the solder bump 3 is greatest, for example, a height that reaches the center position of the height of the solder bump 3. Thereby, a short circuit between the solder bumps 3 can be effectively prevented.

  In the modification shown in FIG. 2A, there is a gap between the columnar structure 4 a and the lower second substrate 2. Since the deformed solder bump 3 swells downward due to gravity, the solder bump 3 may pass through this gap and come into contact with an adjacent solder bump. On the other hand, in the modification shown in FIG. 2B in which the gap is on the upper side, the contact of the solder bump 3 through the gap is avoided. Therefore, the short circuit due to the contact of the bump 3 can be effectively suppressed as compared with the modification shown in FIG.

  2nd Embodiment of this invention is related with the board | substrate connection structure which has arrange | positioned the columnar structure between the nearest and 2nd adjacent solder bump.

  FIG. 3 is an explanatory diagram of a substrate connection structure according to a second embodiment of the present invention. FIG. 3 (a) is a plan view of the substrate connection structure portion, and FIGS. 3 (b) and 3 (c) are diagrams in FIG. CC ′ vertical section and DD ′ vertical section of FIG.

  Referring to FIG. 3, in the second embodiment, a columnar structure 4 is arranged between the closest solder bumps 3 of the solder bumps 3 arranged in a lattice like the first embodiment, A columnar structure 4-2 is arranged between the second adjacent solder bumps 3 located on the diagonal of the lattice.

  By arranging the columnar structures 4 and 4-2 between the closest and second adjacent solder bumps 3 in this way, the solder bumps are deformed and rubbed between the closest solder bumps 3 to be second adjacent solder. It is possible to prevent short circuit due to contact with the bump 3.

  The material and shape of the columnar structure of the second embodiment are the same as those of the first embodiment described above. Similarly, the length (height) of the columnar structure can be made shorter than the distance between the substrates 1 and 2 as in the modification of the first embodiment.

  Next, the arrangement of the columnar structures 4, 4-2, 4a described above will be described.

  FIG. 4 is a plan view for explaining the arrangement of the columnar structures according to the present invention, and represents the planar positions of the solder bumps and the columnar structures in the board connection structure. 4A shows four solder bumps 3-1 and the columnar structures 4A to 4D provided between the solder bump 3-1, which are closest to the central solder bump 3, and FIG. 4B shows the central solder bump. 4 shows four solder bumps 3-2 in the second proximity position.

  Referring to FIG. 4A, columnar structures 4, 4-2, 4a (columnar structures 4A-4D in FIG. 4A) first have solder bumps 3-1 at the closest position. It arrange | positions between the solder bump 3 in a center position.

  The columnar structure 4 </ b> A is disposed on the center line between the solder bump 3-1 at the closest position and the solder bump 3 at the center position, at an intermediate point between the solder bumps 3 and 3-1. By arranging at this position, when the solder bumps 3 and 3-1 are crushed and the diameter is greatly deformed, a short circuit between the adjacent solder bumps 3 and 3-1 can be effectively prevented.

  The columnar structure 4B is completely within the radius of the solder bump 3 from the center line of the solder bump 3-1 at the closest position and the solder bump 3 at the central position (hatched area in FIG. 4A). It is arranged to be included in. Further, the columnar structures 4C and 4D are arranged so that a part thereof is included in the range, and even if two columnar structures 4D are arranged on both sides of the hatched area like the columnar structure 4D. Good. By arranging in this way, the deformed solder bumps 3 are prevented from short-circuiting each other.

  Referring to FIG. 4B, in addition to the columnar structures 4A to 4D described above, the columnar structures 4-2A to 4-2D are located at the second proximity positions of the solder bump 3 and the solder bump 3. It can arrange | position between solder bumps 3-2.

  The columnar structure 4-2A is disposed at a midpoint on the center line of the solder bump 3-2 at the second proximity position and the solder bump 3 at the center position. Further, the columnar structure 4-2A has a range within the radius of the solder bump 3 from the center line of the solder bump 3-2 at the second proximity position and the solder bump 3 at the center position (hatched area in FIG. 4B). The columnar structures 4-2C and 4-2D are arranged so as to be partly included in the hatched area so that they are completely included in (). Thus, in the present embodiment, the columnar structures 4A to 4D and 4-2A to 4-2D are configured by only one or a combination thereof.

  3rd Embodiment of this invention is related with the board | substrate connection structure which has arrange | positioned the spacer outside the solder bump formation area.

  FIG. 5 is an explanatory diagram of a substrate connection structure according to a third embodiment of the present invention. FIG. 5A is a plan view, and FIGS. 5A and 5B are EF ′ in FIG. A vertical section and a FF ′ vertical section are shown.

  Referring to FIG. 1, in the third embodiment, spacers 6 are arranged on the peripheral portion of the first substrate 1 in addition to the substrate connection structure of the first embodiment shown in FIG. 1. Except for the spacer 6, it is the same as the substrate connection structure of the first embodiment, including filling and curing of the underfill 5. By disposing the spacer 6 on the peripheral portion of the first substrate 1, it becomes easy to dispose the first substrate precisely parallel to the second substrate.

  The spacer 6 has the same height as the columnar structure 4 and can be made of the same material and shape as the columnar structure 4, for example. Thereby, since the spacer 6 can be formed simultaneously with the columnar structure 4, manufacture becomes easy.

  FIG. 6 is a cross-sectional view of a modification of the third embodiment of the present invention, and shows a vertical cross section at a position corresponding to the E-E ′ cross section of FIG.

  With reference to FIG. 6A, in the third embodiment modification example, the columnar structure 4 a is erected on the main surface of the first substrate 1, and its height is lower than the spacer 6. That is, the distance between the first and second substrates 1 and 2 is defined by the spacer 6, and a gap is formed between the columnar structure 4 a and the second substrate 2.

  In this modification, since there is a gap between the columnar structure 4a and the second substrate 2, the underfill 5 can be easily injected. On the other hand, since the distance between the substrates 1 and 2 is held by the spacer 6, unnecessary large deformation of the solder bump 3 can be prevented.

  In this modification, the columnar structure 4a and the spacer 6 are different in height. Such a structure can be easily formed by disposing the columnar structure 4a and the spacer 6 on the first and second substrates, respectively. Of course, they may be arranged on the same substrate.

  With reference to FIG. 6B, the columnar structure 4 a can be arranged on the second substrate 2 in the third embodiment modification example. This modification has the same effect as the modification of the first embodiment shown in FIG.

  4th Embodiment of this invention is related with the board | substrate for solder bump connection suitable for comprising the board | substrate connection structure of this invention, and its manufacturing method.

  FIG. 7 is a cross-sectional view of a manufacturing process according to a fourth embodiment of the present invention, and shows a cross section of a solder bump connecting substrate constituting the substrate connecting structure.

  In the fourth embodiment, referring to FIG. 7A, an insulating film 1b is formed on a semiconductor substrate 1 on which a semiconductor integrated circuit is formed, and an electrode 1a is embedded on the insulating film 1b or in the insulating film 1b. Form. In addition, the board | substrate 1 can be manufactured by the same process, even if it is the circuit board for package of a semiconductor device, or an electronic circuit board other than a semiconductor substrate.

  Next, referring to FIG. 7B, ball-shaped solder bumps 3 are bonded onto the electrode 1a.

  Next, referring to FIG. 7C, a photosensitive insulating resin that covers the solder bump 3, for example, a benzocyclobutene resin (BCB resin: manufactured by DuPont, for example) is applied to the substrate 1 so as to cover the solder bump 3. And a flat curing is performed by heat treatment at 180 ° C. for 1 hour to form a flat photosensitive insulating resin layer 7 covering the solder bumps 3. The thickness of the photosensitive insulating resin layer 7 is, for example, about the apex of the solder bump. Since this benzocyclobutene-based resin has a small shrinkage during the heat treatment of the cure, the height and shape of the columnar structure 4 can be precisely manufactured. As the photosensitive insulating resin, polyimide resin, epoxy resin, olefin resin, or phenol photosensitive resin can also be used.

  Next, referring to FIG. 7D, the photosensitive insulating resin layer 7 is exposed, developed, and patterned to form the columnar structure 4 made of the photosensitive insulating resin. As the exposure pattern, a circular pattern was arranged at the position of the cylindrical structure 4 shown in FIG. In addition, it can also be set as the pattern which has arrange | positioned the cylindrical structure 4 which has desired cross-sectional shape in the position of Fig.1 (a), Fig.3 (a), or Fig.5 (a). At this time, the columnar structures 4 and 4-2 and the spacer 6 are manufactured by the same exposure and development process. In addition, the position of these cylindrical structures 4 can also be arrange | positioned like FIG. 4 (a) or FIG.4 (b) as needed.

  Through the above steps, a solder bump connecting substrate 10 having the solder bumps 3 and the columnar structures 4 formed on the main surface, for example, a flip chip, was manufactured. In this solder bump connecting substrate 10, a solder bump (for example, a solder ball) is joined to an electrode 1 a formed on the substrate 1, and a columnar structure 4 made of a photosensitive insulating resin between the solder bumps 3 at the closest position. Is provided.

  Next, a method for manufacturing a substrate connection structure using the solder bump connection substrate 10 will be described.

  With reference to FIG.7 (e), the electronic circuit board by which the electrode 2a is arrange | positioned at the upper surface (main surface) is first prepared as the board | substrate 2 (2nd board | substrate). The electrode 2a is disposed corresponding to the electrode 1a of the solder bump connecting substrate 10 and protrudes from the upper surface.

  Next, the solder bump connection substrate 10 is positioned on the substrate 2 at a position where the electrodes 1 a and 2 a face each other, and the solder bump 3 is bonded to the upper surface of the electrode 2. At this time, since the electrode 2 a protrudes from the upper surface of the substrate 2, the combined height of the electrodes 1 a and 2 a is higher than the height of the columnar structure 4. Therefore, even if the distance between the substrates 1 and 2 is defined by the columnar structure 4, the solder bump 3 is pressed and crushed by the electrode 2a and deformed. The joining can be performed by, for example, reflow or ultrasonic bonding. The reflow is performed at 220 ° C., for example. Thereby, the board | substrate 1 and the board | substrate 2 are connected to the electrode 1a and the electrode 2a via the solder bump 2, and both the board | substrates 1 and 2 are connected and fixed.

  Next, heat treatment is performed at 250 ° C. for 1 hour to cure the photosensitive insulating resin constituting the columnar structure 4. By this curing, the adhesion between the columnar structure 4 and the substrate 1 and the substrate 2 is strengthened, and the strength of the columnar structure 4 is increased.

  Next, the underfill 5 is injected from the periphery of the substrate 1 and cured. Through this step, the substrate connection structure of the present invention described with reference to FIG. 1 (a), FIG. 3 (a) or FIG. 5 (a) is formed.

  5th Embodiment of this invention is related with the board | substrate for solder bump connection which has a columnar structure lower than a solder bump.

  FIG. 8 is a cross-sectional view of a manufacturing process of a fifth embodiment of the present invention, showing a cross section of a solder bump connecting substrate.

  Referring to FIG. 8A, a substrate 1 similar to the substrate 1 of the fourth embodiment shown in FIG. 7A, that is, an insulating film 1b on the main surface and an electrode formed on the insulating film 1b. An integrated circuit substrate 1 having 1a is prepared. Then, a columnar structure 4 a made of an insulator is formed on the substrate 1.

  The columnar structure 4a was formed by exposing and developing the photosensitive insulating resin layer 7 as in the fourth embodiment. However, the present invention is not limited to this, and other methods, for example, a columnar insulator 4 a manufactured in advance can be implanted and formed on the substrate 1. In addition, the planar arrangement position of the columnar structure 4a is the same as the arrangement position of the columnar structures 4, 4-2 and the spacer 6 of the fourth embodiment.

  Next, referring to FIG. 8B, solder balls are bonded onto the electrode 1a, and solder bumps 3 are formed on the electrode 1a. As a result, the solder bump connecting substrate 10 in which the solder bumps 3 and the columnar structures 4a made of an insulator are arranged on the substrate 1 is manufactured.

  In the fifth embodiment, since the solder bumps 3 are arranged and joined after the columnar structures 4a are arranged, the heights of the solder bumps 3 and the columnar structures 4a can be controlled independently. Therefore, it is easy to arrange the columnar structures 4a lower than the solder bumps 3. Further, as the columnar structure 4a, a columnar structure 4 that is substantially the same as or higher than the bump can be disposed as in the first embodiment.

  Similarly to the fourth embodiment, the solder bump connecting substrate 10 of the fifth embodiment is connected to a normal electronic circuit board 2 through the solder bumps 3, and further is injected and cured by injecting underfill. The substrate connection structure of the present invention is formed. At this time, if the columnar structure 4a is sufficiently lower than the solder bump 3, referring to FIG. 2, both the substrates 1 and 2 are connected by the solder bump 3, and the columnar structure having a function of preventing the solder bump 3 from being short-circuited. A substrate connection structure according to a modified example of the first embodiment in which 4a does not function as a spacer is manufactured. When the columnar structure 4a is the same or higher than the solder bump 3, the substrate connection structure of the first embodiment in which the columnar structure 4a functions as the columnar structure 4 as a spacer is described with reference to FIG. Produced.

  The sixth embodiment relates to another method for manufacturing a solder bump connection board having a columnar structure lower than the solder bump.

  FIG. 9 is a cross-sectional view of a manufacturing process according to the sixth embodiment of the present invention, showing a cross section of a solder bump connecting substrate.

  In the sixth embodiment, the process up to the step of bonding the solder bump 3 onto the electrode 1a formed on the main surface of the substrate 1 is the same as the process shown in FIG. 7B of the fourth embodiment.

  Next, referring to FIG. 9A, a benzocyclobutene-based resin is applied to form a photosensitive insulating resin layer 7. The photosensitive resin layer 7 is applied thinner than the height of the solder bump 3. Therefore, the photosensitive resin layer 7 is thin between the solder bumps 3, and has a height of about 30 μm, for example, at a substantially central position of the solder bumps 3. Next, a half cure is performed at 180 ° C. for 1 hour.

  Next, the photosensitive resin layer 7 is exposed and developed to form a columnar structure 4 a made of a photosensitive resin between the closest solder bumps 3. Next, the columnar structure 4a is strengthened by curing at 250 ° C. for 1 hour. Through this step, the solder bump connecting substrate 10 having the columnar structure 4a lower than the solder bump is manufactured.

  In the sixth embodiment, since the columnar structure 4a can be formed by applying, exposing and developing a photosensitive resin, the solder bump connecting substrate 10 can be easily manufactured.

  7th Embodiment of this invention is related with the board | substrate 20 for solder bump connection in which the columnar structure of the insulator was arrange | positioned.

  FIG. 10 is an assembly diagram of the seventh embodiment of the present invention, and shows a cross section of the solder bump connecting substrate.

  Referring to FIG. 10, the solder bump connecting substrate 10 of the seventh embodiment is erected on the upper surface (main surface) of the substrate 2, for example, an electronic circuit substrate, between the electrode 2a and the electrode 2a at the nearest position. A columnar structure 4a made of an insulating material is provided. This columnar structure 4a is formed by patterning that exposes and develops the photosensitive insulating resin layer 7 as in the fifth embodiment described. Of course, it may be manufactured using other methods.

  From above the solder bump connecting substrate 10, the flip chip 30 in which the solder bump 3 is formed on the main surface of the substrate 1 is aligned with the position of the solder bump 3 and the electrode 2 a and joined by reflow or ultrasonic bonding. Next, the underfill 5 is injected between the substrates 1 and 2 and cured to form the substrate connection structure of the present invention. In addition, when the height of the columnar structure 4a is high, the board | substrate connection structure of 1st Embodiment shown in FIG. 1 is formed, and when low, the board | substrate connection structure of 1st Embodiment modification shown in FIG. 2 is formed.

  The substrate for solder bump connection according to the seventh embodiment can form the substrate connection structure of the present invention using a normal substrate connected by using solder bumps 3 such as flip chip or grid array circuit boards. .

  FIG. 11 is an assembly diagram of the eighth embodiment of the present invention, in which the solder bump connection substrate 10 of the sixth embodiment shown in FIG. 9B and the electronic circuit substrate 2 on which the spacer 6 is formed are joined. Represents a connection structure.

  In the eighth embodiment, the electronic circuit board 2 in which the spacer 6 is erected on the main surface is used. The spacer 6 is made of an insulating material and is disposed outside the electrode formation region (that is, the solder bump 3 formation region) as shown in FIG. In addition, it can manufacture by exposure and image development by making the spacer 6 material into photosensitive insulating resin.

  On top of this, the solder bumps 3 and the electrodes 2a are joined by aligning them so that the solder bumps 3 coincide with the electrodes 2a. Thereafter, underfill is injected and cured, and the substrate bonding structure of the present invention in which the distance is maintained by the spacer 6 as shown in FIG. 5 is manufactured.

  In the eighth embodiment, since the columnar structure 4a and the spacer 6 are formed on different substrates 1 and 2, respectively, the columnar structure 4a and the spacer 6 can be manufactured without being affected by each interference, and manufacturing is easy.

  The ninth embodiment of the present invention relates to a substrate connection structure in which solder bumps 3 are formed using solder bump connection substrates 1 and 2 formed on first and second substrates 1 and 2.

  FIG. 12 is a cross-sectional view of a ninth embodiment of the present invention, showing a cross section of a solder bump connecting substrate.

  In the ninth embodiment, a flip chip substrate 1 having an electrode 1a formed on the main surface and an electronic circuit substrate 2 having an electrode 2a formed on the main surface are used. Solder bumps 3 are formed on the electrodes 1a and 2a of the substrates 1 and 2, respectively. A columnar structure 4 made of an insulator having a height that functions as a spacer is provided on one of the substrates 1 and 2, for example, the main surface of the substrate 1. The arrangement and formation method of the columnar structures 4 can be formed by the same method as in the above fourth to ninth embodiments.

  The substrate 1 and the substrate 2 are joined together with the solder bumps 3 of each other. At this time, the substrates 1 and 2 are pressed so that the space between the substrates 1 and 2 is held by the spacer 6. Next, the underfill 5 is injected from the periphery of the substrate 1 and cured to produce the substrate connection structure of the present invention shown in FIG.

  In the ninth embodiment, even in the columnar structure 4 that functions as a spacer, the height of the columnar structure 4 can be made lower than the height of the solder bump 3, so that it has been described with reference to FIG. The substrate 1 can be easily formed on a solder bump connecting substrate by the method of the fourth embodiment in which the photosensitive insulating resin layer 7 covering the solder bumps 3 is formed flat.

The present invention described above discloses the invention described in the following supplementary notes.
(Supplementary Note 1) Solder by facing a plurality of first electrodes formed on the main surface of the first substrate and a plurality of second electrodes formed on the main surface of the second substrate corresponding to the first electrode In a semiconductor device structure connected by bumps and filled with underfill between the main surfaces of the first and second substrates,
A semiconductor device having a columnar structure made of an insulating material between each solder bump.
(Supplementary note 2) The semiconductor device according to supplementary note 1, wherein the columnar structure is provided between the solder bumps at the closest positions.
(Supplementary note 3) The semiconductor device according to Supplementary note 1 or 2, wherein the columnar structure is also provided between the solder bumps in a second proximity position.
(Additional remark 4) The said columnar structure consists of photosensitive insulating resin, The semiconductor device of Additional remark 1, 2 or 3 characterized by the above-mentioned.
(Supplementary Note 5) In a solder bump connection substrate having a plurality of electrodes formed on the main surface and solder bumps formed on the electrodes,
A solder bump connection substrate, wherein a columnar structure made of an insulator standing on the main surface of the solder bump connection substrate is provided between the solder bumps at the closest positions.
(Supplementary Note 6) In a solder bump connection substrate provided with a plurality of electrodes on the main surface for connecting the first substrate using a plurality of solder bumps formed on the main surface of the first substrate,
A solder bump connection substrate, wherein a columnar structure made of an insulator standing on the main surface of the solder bump connection substrate is provided between the electrodes at the closest positions.
(Additional remark 7) Furthermore, the said columnar structure is provided also between the said solder bumps in a 2nd proximity position, The board | substrate for solder bump connection of Additional remark 5 or 6 characterized by the above-mentioned.
(Supplementary note 8) The solder bump connection substrate according to supplementary note 5, 6 or 7, wherein the columnar structure is made of a photosensitive insulating resin.
(Appendix 9) forming a plurality of electrodes on the main surface of the substrate;
Forming solder bumps on the electrodes;
Forming a photosensitive insulating resin layer on the substrate;
And a step of exposing and developing the photosensitive insulating resin layer to form a columnar structure made of the photosensitive insulating resin layer between the electrodes at the closest positions. Manufacturing method.
(Additional remark 10) The manufacturing method of the board | substrate for solder bump formation of Additional remark 9 characterized by forming the said columnar structure between the said electrodes in a 2nd proximity position.
(Supplementary note 11) The method for manufacturing a solder bump connecting substrate according to supplementary notes 9 and 10, wherein the solder bump is formed after the step of forming the columnar structure.
(Appendix 12) A step of forming a plurality of electrodes on the main surface of the substrate;
Forming solder bumps on the electrodes;
Forming a photosensitive insulating resin layer on the substrate;
Exposing and developing the photosensitive insulating resin layer to form a columnar structure composed of the photosensitive insulating resin layer between the electrodes at the closest positions; and
On the main surface of the second substrate having a plurality of second electrodes formed on the main surface corresponding to the first electrode, the first electrode and the second electrode are opposed to each other by the solder bumps. Connecting, and
And filling the space between the main surfaces of the first and second substrates with an underfill.

  By applying the present invention to the connection of a silicon substrate, a package substrate, or an electronic circuit substrate of an integrated circuit, an electronic circuit device having high adhesive strength and high reliability can be manufactured.

Board connection structure explanatory drawing of 1st Embodiment of this invention Sectional drawing of a modification of the first embodiment of the present invention Board connection structure explanatory drawing of 2nd Embodiment of this invention. The top view for demonstrating arrangement | positioning of the columnar structure of this invention Board connection structure explanatory drawing of 3rd Embodiment of this invention. Sectional drawing of a modification of the third embodiment of the present invention Sectional view of the manufacturing process of the fourth embodiment of the present invention Sectional view of manufacturing process of fifth embodiment of the present invention Sectional view of the manufacturing process of the sixth embodiment of the present invention Assembly drawing of seventh embodiment of the present invention Assembly drawing of eighth embodiment of the present invention Sectional view of manufacturing process of ninth embodiment of the present invention Illustration of conventional board connection structure

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 1st board | substrate 1a, 2a Electrode 1b Insulating film 2 2nd board | substrate 3, 3-1, 3-2 Solder bump 4, 4-2, 4A-4D, 4-2A-4-2D Columnar structure 4a Columnar structure 5 Underfill 6 Spacer 7 Photosensitive insulating resin layer 10, 20 Solder bump connection substrate 30 Flip chip 41 LSI
41a, 42a Electrode 42 Electronic circuit board 43 Solder bump 44 Reticulated spacer

Claims (5)

A plurality of first electrodes formed on the main surface of the first substrate and a plurality of second electrodes formed on the main surface of the second substrate corresponding to the first electrodes are opposed to each other by solder bumps. In the semiconductor device in which the space between the main surfaces of the first and second substrates is filled with underfill,
A semiconductor device having a columnar structure made of an insulating material between each solder bump.   The semiconductor device according to claim 1, wherein the columnar structure is provided between the solder bumps at the closest positions.   The semiconductor device according to claim 1, wherein the columnar structure is also provided between the solder bumps in a second proximity position. Forming a plurality of electrodes on the main surface of the substrate;
Forming solder bumps on the electrodes;
Forming a photosensitive insulating resin layer on the substrate;
And a step of exposing and developing the photosensitive insulating resin layer to form a columnar structure made of the photosensitive insulating resin layer between the electrodes at the closest positions. Manufacturing method. Forming a plurality of electrodes on the main surface of the substrate;
Forming solder bumps on the electrodes;
Forming a photosensitive insulating resin layer on the substrate;
Exposing and developing the photosensitive insulating resin layer to form a columnar structure composed of the photosensitive insulating resin layer between the electrodes at the closest positions; and
On the main surface of the second substrate having a plurality of second electrodes formed on the main surface corresponding to the first electrode, the first electrode and the second electrode are opposed to each other by the solder bumps. Connecting, and
And filling the space between the main surfaces of the first and second substrates with an underfill.

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