Abstract: A semiconductor device assembly and a semiconductor device are provided which both can ensure reliability after a mounting process. The semiconductor device includes a semiconductor element equipped with bumps on an electrode patterned surface thereof for external connection. In the semiconductor device mounted on a substrate in the semiconductor device assembly, a semiconductor element shaped to have a thickness ranging 200 &mgr;m to 10 &mgr;m has reduced flexural rigidity so as to be easily deflected. In the status that the bumps are joined to corresponding circuitry electrodes on the substrate, the semiconductor element can deflect at other portion than its surface between two adjacent bumps according to contraction and distortion of the substrate. This allows the bumps to be dislocated in a parallel direction with a surface of the semiconductor element, hence relieving a stress developed by the contraction of the substrate at the joint positions between the bumps and the circuitry electrodes.

Abstract: A conductive ball transferring apparatus including: an arranging member having in its top face a plurality of recesses in a predetermined arrangement pattern each capable of receiving one conductive ball therein; a tilting mechanism for tilting the arranging member with respect to a horizontal plane; a speed controller for controlling the moving speeds of the conductive balls that move along the top face of the tilted arranging member in a direction the arranging member has been tilted; and a transferring head for picking up the conductive balls arranged by the arranging member and transferring them onto predetermined positions. With this structure, the moving speeds of the conductive balls are stabilized and the conductive balls are arranged into the recesses quickly without fail, and thereby the transferring head can pick up these conductive balls onto predetermined positions promptly.

Abstract: A semiconductor device having a thinned semiconductor element allowed to be easily handled, and a method of manufacturing the device are provided. The semiconductor device includes a semiconductor element and a bumper member bonded, as a reinforcing member, to a back surface opposite to an electrode-formed surface of the semiconductor element with an adhesive. The adhesive has a low elastic modulus and easily expands and contracts after bonding, and bonds the semiconductor element to the bumper member while allowing the semiconductor element to be deformed. Thus, the semiconductor device can easily be handled, and the semiconductor element can be deformed in responsive to the deformation of a substrate after being mounted. In addition, a thermal stress in a heat cycle can be alleviated effectively.

Abstract: The method of manufacturing a semiconductor device of the present invention comprises: forming a resin layer on a surface of a semiconductor wafer on which a plurality of semiconductor elements are formed, forming through-holes on the resin layer, a first cutting of either the semiconductor wafer or the resin layer, mounting conductive balls on the through-hole, connecting the conductive ball to electrodes of the semiconductor element, and a second cutting for dividing the wafer into each piece of semiconductor devices. With the processes of the present invention, conductive balls can be easily and effectively mounted on a wafer under optimum conditions, without failure such as slipping or falling down from the required position. This fact contributes to an increased efficiency and a good productivity in the production of semiconductor devices.

Abstract: A method of mounting bumped electronic components without using a flux during the solder joining process, which is low in cost and offers high reliability of the assembly. Resin adhesive 4 containing filler particles 4a is applied to a board 1 formed with electrodes 2, and a bumped electronic component 5 is mounted onto the board 1 to press the bumps 7 of the electronic component 5 against the electrodes 2 of the board 1. As a result, the oxide films 7a over the surfaces of the solder bumps 7 are broken by the filler particles 4a present in a gap between the lower ends of the solder bumps 7 and the surfaces of the electrodes 2, thus exposing the solder. This process eliminates the need for using the flux when the solder bumps 7 are melted and soldered to the electrodes 2, and therefore the cleaning process after soldering is not required, assuring high reliability of the assembly.

Abstract: A solder bump formation method and solder bump mounting method for forming a solder bump by soldering a solder ball 9 onto an electrode 2 provided at the bottom of a cavity 3 on a substrate 2 which has an opening shape through which the solder ball 9 cannot go. Metal paste 5, containing metal having a higher liquidus temperature than that of solder used for the solder ball 9, is filled into the cavity 3. The solder ball 9 is placed on the cavity 3, and then heated to the temperature higher than the liquidus temperature of the solder ball 9. During the heating process, metal in the metal paste 5 remains unmelted in the cavity 3 when the solder ball 9 melts. This enables the metal to direct the melted solder to the electrode 2 at the bottom of the cavity 3, achieving good soldering.

Abstract: A method of soldering a bumped work without using flux is provided by the steps of vacuum-sucking the bumped work on a head, pressing a bump against a pad of another work, causing a projection of the bump to partially break an oxide film on the solder portion, to pierce it, and to be placed thereon, and cooling and solidifying the molten solder portion. The surface of the solder portion is coated by the oxide film as a hard shell, so that, even if the bump is firmly pressed against the solder portion, the solder of the solder portion does not flow sidewise, and a solder bridge is not produced.

Abstract: A suction head sucks up conductive balls to its suction holes, and mounts them on pads of said workpiece. That is, the suction head is lowered so as to land the conductive balls onto the pads, and then is raised, and a positive pressure is applied in a space defined in the suction head and communicated with the suction holes and thereafter, the positive pressure is released so as to effect the atmospheric pressure in the space. As a result, the conductive balls are smoothly and surely separated from the suction holes and mounted onto the pads of the workpiece. Thereby it is possible to rapidly mount the conductive balls sucked at the lower surface of the suction head onto the pads of the workpiece.

Abstract: A method of transferring conductive balls via a suction head without picking up errors and mounting errors includes moving a suction head with pores towards the conductive balls located in a case and applying a vacuum pressure to the pores to suck and pick up the conductive balls. While the suction head is moved away from the case, the suction head is vibrated by oscillators at different frequencies changed within a predetermined frequency range, thereby dropping redundant conductive balls from the suction head. Further, the suction head is moved to a position above a work piece and moved towards the work piece. The pores are communicated with atmosphere to mount the conductive balls onto the work piece. While the suction head is away from the work piece, the suction head is vibrated by oscillators at different frequencies changed within a predetermined frequency range.

Abstract: An electronic parts mounting method comprises a first step of forming precoatings on electrodes of a circuit board, a second step of depressing the bumps of an electronic part having bumps eat into the electrodes by pressing the electronic part having bumps to the circuit board with a mounting unit, and interposing a bonding agent between the electronic part having bumps and the circuit board, and a third step of carrying the circuit board to a thermal compression bonding unit and pressing while heating the electronic part having bumps to the circuit board with a thermal compression bonding head. This method is capable of preventing the electronic part having bumps from being deviated during carriage and allows works to be carried out in parallel with one another at a plurality of working stages, thereby enhancing a working efficiency.

Abstract: The mounting structure of an electronic component having bumps includes a multi-layer substrate provided with an outermost layer substrate having electrode on the top thereof and a lower layer substrate comprising at least one layer substrate joining the bottom of the outermost layer substrate, an electronic component having bumps bonded with the electrodes formed on the top of the outermost layer substrate for connecting the electronic component and the substrate, and under-fill resin formed between the electronic component and the outermost layer substrate, in which the coefficient of linear thermal expansion of the under-fill resin is larger than that of the electronic component, but smaller than that of the outermost layer substrate.

Abstract: An improved structure of an electronic part with solder bumps is provided. The electronic part includes, for example, an IC chip and a board. The solder bumps are disposed on the bottom surface of the board and have a melting point greater than a thermal deformation temperature of the board. With this arrangement, if the curved board is bonded to a substrate in a soldering process, the solder bumps are solidified at a higher temperature than the thermal deformation temperature of the board during a cooling process, thereby preventing the curved board which has been straightened once above the thermal deformation temperature from being returned to its original shape. Several modifications are disclosed.

Abstract: An apparatus for mounting electrically conductive balls includes a mounting head which has an attracting tool with a number of attracting holes in its lower surface and attracts electrically conductive balls through a vacuum. The attracting tool is resiliently supported by the mounting head through springs. A flux is stored in a container at a predetermined depth. The electrically conductive balls attracted to the attracting tool project from its lower surface by a length larger than the depth of the flux. When the attracting tool is lowered, the electrically conductive balls contact a bottom surface of the container in a resilient manner due to spring tension of the springs. Then, by raising the attracting tool, the flux adheres to lower surfaces of the electrically conductive balls. With the flux kept at a proper depth, it can be made adhere in appropriate amount to all the electrically conductive balls at one time.

Abstract: A conductive ball mounting apparatus and a mounting method for mounting a conductive ball for forming a bump without erroneously mounting an additional conductive ball in a workpiece, comprising a workpiece positioning section, a conductive ball feeding section, a mounting head provided with a plurality of suction holes each of which has a recess capable of storing one conductive ball on the bottom surface of the head, a moving device for moving the mounting head between the workpiece positioning section and the conductive ball feeding section, and a detecting device for detecting conductive balls erroneously additionally attached to the bottom surface of the mounting head without being stored in recesses arranged on the moving route of the mounting head.

Abstract: An electronic device includes a substrate, a chip attached thereon, and a molded body formed on the substrate for sealing the chip on the substrate. The electronic device further includes bumps formed at the underside of the substrate for connection to electrodes of a printed board. In an electronic device mounting method, a first correlation between a magnitude of warp of the electronic device and a heating temperature of the electronic device is derived. The warp is caused by a difference in thermal expansion coefficient between the molded body and the substrate. In the method, a second correlation between the magnitude of warp of the electronic device and a failure rate of coupling between the bumps and the electrodes is further derived. The method further derives, based on the first and second correlations, a heating temperature which causes no coupling failure between the bumps and the electrodes.

Abstract: An electronic part is tacked to a circuit board, leads of the electronic part being made into contact with cream solder built up on the circuit board, and thereafter, the circuit board is heated up so as to melt the cream solder in order to solder the electronic part to the circuit board. In this procedure, the melting temperature of a hardener in the tacking bond, that is, the hardening temperature of the tacking bond--is higher than that of the cream solder, thereby making it possible to prevent hindrance to sinking of the lead terminal of the electronic part into the melted cream solder.

Abstract: A printed circuit board comprising a plurality of lands onto which a plurality of leads of an electronic component are soldered. These lands are arrayed in parallel one another. Each of these lands includes a narrow portion basically extending in a longitudinal direction thereof and having a predetermined constant width, and a wide portion protruding laterally from both edges of the narrow portion.

Abstract: A suction head is introduced into a ball reservoir holding conductive balls, such as solder balls, and a plurality of suction holes formed in a suction surface of the suction head, hold the conductive balls by suction, respectively. Then, the suction head is moved into a position above a workpiece placed in position, and the suction is released from the conductive balls held on the suction head, thereby placing these conductive balls onto the workpiece. The suction head is vibrated or moved within the ball reservoir so that each of the suction holes can positively hold one conductive ball, thus preventing extra conductive balls from sticking to the suction head.

Abstract: A solder bump 3a is formed on an electrode 2 provided on a printed circuit board 1. First, a core 3 is formed on the electrode 2. Then, solder paste 3' is coated on the core 3 so as to cover an entire surface of the core 3. Subsequently, the solder paste 3' is heated until the solder paste 3' fuses together with the core 3, thereby forming the bump 3a on the electrode 2.

Abstract: The invention relates to a method for forming bump electrodes on an electronic part such as a chip or a substrate. Conventional methods for forming bump electrode had a factor causing high cost, but with the invention, instead of solder balls, low cost solder wires are used, that is, solder wires are cut in a predetermined length, the cut solder wires are vacuum-attracted to the lower face of a pick up head and transferred onto a chip, then the solder pieces transferred are heated to melt, then cooled to solidify and results in forming bump electrodes of hemisphere shape.