Showing papers on "Anodic bonding published in 1984"

Process for the direct bonding of metal to ceramics

Abstract: In directly bonding a metal to ceramics, in accordance with the invention, that surface of a metal component which is to be bonded by heating to a ceramic substrate is provided with parallel-running grooves before the preoxidation. The grooves make it possible to optimize the quantity of oxygen available at the bonding location and provide good flow behavior of the melt. As a result, a bond with good adhesion is obtained. Moreover, there is no formation of a thicker oxide layer on the free smooth surface of the metal component.

Pressure transducer and mounting

Abstract: A capacitive pressure transducer whose diaphragm is formed of single crystal, highly doped silicon by etching in opposite sides the recesses which define the deflecting region of the diaphragm. This deflecting region serves as one electrode of the transducer. Two support plates of silicon are anodically bonded to opposite sides of the diaphragm along its periphery using thin layers of borosilicate glass to form with the etched recesses pressure receiving cavities. These thin layers of borosilicate glass are interposed between the diaphragm and a support plate, and extend over the entire surface of the support plate facing the diaphragm to provide for electrical isolation as well as the bonding between the diaphragm and the support plates. These layers of glass are made as thin as possible consistent with the need to maintain the stray capacitance below a certain value. The transducer is mounted to a pressure receiving assembly by using a silicon stub having a passage for communicating one pressure to be measured to the transducer. The stub is joined at one end to the transducer by anodic bonding using a thin layer of borosilicate glass. A weldable tube is attached to the stub. This tube is long with respect to the stub and has a reduced diameter at one end which fits into the passage of the stub. The reduced diameter is kept at a minimum. The tube is welded to the pressure receiving body at its end to provide mechanical isolation for the transducer.

Low parasitic capacitance pressure transducer and etch stop method

Abstract: A capacitive pressure transducer has a pedestal 25 formed in a silicon layer 14 surrounded by a moat 26 extending through the silicon layer, with borosilicate glass 17, 22 at the edges of the silicon layer forming the walls of the pressure chamber, with a wafer 28 of silicon bonded thereto. The pedestal 25 is joined to the walls of the vacuum chamber by borosilicate glass 16, whereby it is wholly, electrically isolated therefrom. A method of forming a capacitive pressure transducer utilizing the variable etch rates of aluminum, glass and silicon, together with field assisted bonding, is also disclosed.

Ceramic bonded structure and method of manufacturing the same

Abstract: A ceramic bonded structure with a high bonding strength has a first member of a ceramic, a ceramic-modified bonding layer formed on at least a bonding surface of the first member by a thermal treatment, a metal layer formed on the ceramic-modified bonding layer, and a second member of a ceramic or metal bonded with the first member through the metal layer.

Coatings for ceramic bonding capillaries

Abstract: A bonding apparatus for bonding lead wires to a semiconductor surface includes a supply spool that contains a supply of the bonding wire that is fed to a capillary that is made of a non-conductive material. An electric arc forms a ball on the tip of the arc and the ball is retracted into the capillary. The ball is heated and compressed onto the semiconductor substrate and is then stitched over to a second bonding point which in most applications is the interface pin of the semiconductor device. The capillary has a non-conductive end that prevents coating of the capillary tip with the molten metal that results from the arcing of the bonding wire.

Thermocompression bonding apparatus

Abstract: PURPOSE:To restrain a silicon sheet from deteriorating without bonding the sheet on a compression bonding heater making it feasible to shift an abutting part thereof against a work very easily even if it is deteriorated by a method wherein the silicon sheet with winding means is provided so that it is held between a compression bonding heater and a work during the thermocompression bonding process. CONSTITUTION:A thermocompression bonding part of film end 3 is covered with a silicon sheet 17 by means of lowering a compression bonding head. Then a compression bonding heater 12 is lowered to hold the silicon sheet 176 heating and compression bonding the film end 3. After the thermocompression bonding process, the compression bonding head is lifted to separate the silicon sheet 17 again from the compression bonding heater 12. Finally the silicon sheet 17 wound round winding rolls 18a, 18b so that the abutting position against a work may be shifted freely may be restrained from deteriorating making it feasible to shift the abutting part of silicon sheet 17 against a work very easily.

Apparatus and method for thermo bonding metallic surfaces

Abstract: Apparatus and method for heat bonding surfaces together. A laser beam (21) is applied to the opening (18) in a bonding tip (15). The bonding tip (15) includes a conically tapered central passage (17), forming a black body cavity, extending from the opening (18) to an exit bore (16). The heated tip end around the bore (16) is applied to the fuse- able surfaces in either a thermo-compression or thermosonic bonding operation. For the latter operation an ultrasonic generator (20) is coupled to the bonding tip (15). The bonding tip (15) is heated by absorbing energy from the laser beam.

Semiconductor pressure sensor

Abstract: PURPOSE:To achieve a drastic reduction in the number of parts and man-hours and a higher airtightness by a direct joining of a stem and a silicon diaphragm in stead of abolishing the pedestal. CONSTITUTION:The surface of a stem 1 made of silicon ceramics approximate in the linear expansion modulus to a silicon diaphragm 4 having a piezoelectric resistance type strain-sensitive element is partially metalized and a terminal pin 2 and a pressure introducing pipe 3 are soldered thereon while it is put together with the diaphragm 4 by an anodic bonding technique. A bonding is done wire 5 and then, a joint 7 between a cap 6 and the stem 1 is gold plated after metalized. The cap 6 is sealed with a solder in a furnace with a solder dipping once applied on the side of the cap 6 thereby enabling easy and airtight anodic junction of the stem 1 and the diaphragm 4.

Method of wire bonding with applied insulative coating

Abstract: The invention provides a bonding wire which prevents electric short-circuiting even if it comes into contact with another bonding wire, a bonding method using the same, and a semiconductor device including the same. The bonding wire comprises a core wire made of a metal and an insulating film which surrounds it. The insulating film is eliminated from the ends of the bonding wire by thermal decomposition and scattering, while simultaneously each end of the bonding wire is connected to a bonding pad of the semiconductor device or to a lead frame. In the semiconductor device, the bonding pads are respectively connected to lead frames by means of the bonding wires.

Package of piezoelectric oscillator

Abstract: PURPOSE:To attain automation of manufacturing process and ease of mass-production, by forming a conductor pattern on a glass or ceramic substrate as an electrode lead section, connecting and fixing electrically the electrode of a piezoelectric oscillator, bonding a sealing cover and sealing the piezoelectric oscillator. CONSTITUTION:A Cr layer 2 having a strong affinity with glass is vapordeposited to a prescribed position on a glass plate 1 being the base of a package at first, a Cr-Au alloy 3 is vapor-deposited on it and an Au layer 4 is further vapor-deposited on it to complete the vapor-deposition process and conductive patterns 5, 5... are completed. Then, a ring pattern 7 passing the Cr layer 2 of the conductor patterns 5, 5... is formed on the glass base 1 with glass solder as the bonding part of the sealing glass cover 6. After the electrode lead of the piezoelectric oscillator 8 is soldered at the end of the center of base plate 1 of the conductor patterns 5, 5..., the glass sealing cover is applied and heated in a furnace to 150-200 deg.C to complete the package. Further, shield electrodes 21, 22 are provided respectively on the lower surface of the glass base plate 1 and the upper surface of the glass sealing cover 6 with the vacuum-deposition or printing.

Process for bonding germanium to metal

Abstract: A germanium component (1) is bonded to a second component (3) of metal, or metal-surfaced ceramic, by a braze composed of a first metal (6), which is constituted by or deposited on the surface of the second component, one or two additional metals (7,8) deposited on or inserted between the component surfaces, and germanium derived from the component, the additional metal or metals and germanium forming an alloy, preferably an eutectic, which interacts with the first metal to form a molten braze at a temperature below the melting points of the components Specifically, for the manufacture of an infra-red window for a laser, a germanium window is bonded to a Nilo K or Kovar support by coating the latter with nickel or cobalt, introducing silver or copper either as coatings on, or as a shim inserted between, the mating surfaces, and heating the assembly to 680-690 DEG C The braze withstands temperatures used for outgassing the device

Method of burnishing malleable films on semiconductor substrates

Abstract: An improved burnishing method suitable for planarizing bonding pads on fragile semiconductor devices is disclosed. The method comprises imparting scratches of predetermined depth and spacing onto a glass slide. The bonding pad surface is contacted to the scratched glass surface under a desired pressure and a relative motion is established therebetween. The motion is continued until a smooth, defect-free bonding pad surface has been provided.

Diffusion bonding of NiZn ferrite and nonmagnetic materials

Abstract: Diffusion bonding of dissimilar ceramics can be accomplished by the application of pressure only while the ceramics are at a temperature where their respective thermal expansion curves cross. A process for manufacturing magnetic head cores is disclosed wnere a NiZn ferrite is bonded by diffusion co a nonmagnetic ceramic by heating the core pieces to the crossover temperature and them applying the bonding pressure. The pressure can be removed either before or after the bonded pieces are cooled.