摘要:
[Problems] A conventional process for producing a solder preform in which a predetermined amount of high-melting metal particles are directly put into molten solder and stirred, requires a long time for dispersing the high-melting metal particles by stirring. Therefore, in the conventional method for producing a solder preform, dissolution of the high-melting metal particles into the molten solder occurred during stirring, and their particle diameters became small. If a semiconductor chip and a substrate are soldered with a solder preform containing metal particles having such decreased diameters, the space between portions being soldered becomes narrow, and a sufficient bonding strength is not obtained.[Means for Solving the Problems] In the present invention, a premixed master alloy having a higher proportion of the high-melting metal particles in solder is first prepared, then the premixed master alloy is put into molten solder to disperse the high-melting metal particles. As a result, the high-melting metal particles can be uniformly dispersed in solder in a short length of time. Accordingly, a solder preform which is obtained by the process for producing a solder preform according to the present invention can maintain a predetermined clearance between portions being soldered, and a sufficient bonding strength is obtained.
摘要:
An optical disc device includes a conductive member of a bezel assembly with openings formed by a plurality of parting lines, and gaskets are attached to the upper and lower sides of the conductive member using conductive adhesion bond.
摘要:
A mixed mother alloy is prepared from a solder mixture comprising a pyrolyzable flux and high melting point metal particles, the mixed mother alloy is charged into a large amount of molten solder and stirred, and a billet is prepared. The billet can then be extruded, rolled, and punched to form a pellet or a washer, for example.
摘要:
An electronic component having a semiconductor element bonded to a substrate with solder has a decreased bonding strength if there is not a suitable clearance between the semiconductor element and the substrate. Therefore, a solder preform having high melting point metal particles dispersed in solder has been used in the manufacture of electronic components. However, when an electronic component was manufactured using a conventional solder preform, there were cases in which the semiconductor element leaned or the bonding strength was not adequate.A solder preform according to the present invention has a variation in the size of high melting point metal particles which is at most 20 micrometers when the metal particle diameter is 50 micrometers, and an alloy layer of the high melting point metal particles and the main component of solder is formed around the high melting point metal particles. In addition, no voids at all are present in the solder. An electronic component according to the present invention has a semiconductor element bonded to a substrate with the above-described solder preform and has excellent resistance to heat cycles.
摘要:
Endoscopic system 40 comprises composite optical fiber 34 that consists of a large-diameter, laser light transmitting optical fiber surrounded by a large number of image transmitting fibers that are bundled together to form an integral assembly with the central fiber, laser applying and image observing optical unit 42 that is connected to the eyepiece portion of said composite optical fiber such that it launches laser light into said large-diameter optical fiber and that the image being transmitted through said image transmitting optical fiber is focused on a camera to become observable, and an illuminating light transmitting unit that transmits illuminating light to the tip of the objective portion of said composite optical fiber for irradiation purposes.
摘要:
An elevator in which a driving apparatus, a traction sheave, and a counterweight-side rope hitching portion are arranged above one rail of the right and left cage-side guide rails, while a cage-side rope hitching portion and a speed governor are arranged above the other rail of the right and left cage-side guide rails. Since a control panel is arranged along a rear inner wall surface of the machine room, a large operation space can be secured in a center part of the floor of the machine room. Further, since a machine beam can be extended at full length in the back and forth direction in the machine room, no additional building-side receiving beam is needed.
摘要:
The object of the present invention is to provide a light-emitting element mounting member and a semiconductor device using the same that is easy to process and that allows adequate heat dissipation.A light-emitting element mounting member 200 includes: a substrate 2 including an element mounting surface 2a mounting a semiconductor light-emitting element 1 and first and second conductive regions 21, 22 disposed on the element mounting surface 2a and connected to the semiconductor light-emitting element 1; a reflective member 6 including a reflective surface 6a defining an internal space 6b for housing the semiconductor light-emitting element 1 and containing a metal disposed on the element mounting surface 1a; and a metal layer 13 disposed on the reflective surface 6a. The reflective surface 6a is sloped relative to the element mounting surface 2a so that a diameter of the internal space 6b is greater away from the element mounting surface 2a.
摘要:
A semiconductor device for adequately removing heat generated by a semiconductor element is provided. A semiconductor device 100 is equipped with a substrate 2, having a bottom surface 2b and an element mounting surface 2a which is positioned on the opposite side of bottom surface 2b, and a semiconductor element 1, having a main surface 1a which is mounted onto element mounting surface 2a. With L being the length in the long direction of main surface 1 and H being the distance between bottom surface 2b and element mounting surface 2a, the ratio H/L is 0.3 or greater. When the semiconductor element is a light emitting element, element mounting surface 2a is a cavity 2u, and element 1 is provided in cavity 2u. A metal layer 13 is provided on the surface of cavity 2u. In addition, when an electrode 32 which connects to an external part is provided on main surface 1a, on the cavity side of the part which connects with electrode 32, main surface 1a is provided with a groove. The groove is for preventing outward flow of connection member 34 of electrode 32.
摘要:
A semiconductor device for adequately removing heat generated by a semiconductor element is provided. A semiconductor device 100 is equipped with a substrate 2, having a bottom surface 2b and an element mounting surface 2a which is positioned on the opposite side of bottom surface 2b, and a semiconductor element 1, having a main surface 1a which is mounted onto element mounting surface 2a. With L being the length in the long direction of main surface 1 and H being the distance between bottom surface 2b and element mounting surface 2a, the ratio H/L is 0.3 or greater. When the semiconductor element is a light emitting element, element mounting surface 2a is a cavity 2u, and element 1 is provided in cavity 2u. A metal layer 13 is provided on the surface of cavity 2u. In addition, when an electrode 32 which connects to an external part is provided on main surface 1a, on the cavity side of the part which connects with electrode 32, main surface 1a is provided with a groove. The groove is for preventing outward flow of connection member 34 of electrode 32.
摘要:
There is provided an machineroom-less elevator which can reduce the pit depth in a bottom part of an elevator shaft, mostly perform maintenance work on an upper space of a cage, and reduce a top clearance. A pair of right and left cage-side sheaves are disposed in the upper space of the cage, and the rotational axes of the traction sheave and the cage-side sheaves are extended in the longitudinal direction. A sheave supporting beam to rotatably support cage-side sheaves is disposed in a space between and upper beam of the cage frame and a ceiling of the cage, and disposed below rotary shafts of the cage-side sheaves.