摘要:
A laser device is bonded to a diamond submount by means of a procedure including (1) codepositing an auxiliary layer, on a layer of barrier metal that has been deposited overlying the submount, followed by (2) depositing a wetting layer on the auxiliary layer, and (3) by depositing a solder layer comprising alternating metallic layers, preferably of gold and tin sufficient to form an overall tin-rich gold-tin eutectic composition. The barrier metal is typically W, Mo, Cr, or Ru. Prior to bonding, a conventional metallization such as Ti-Pt-Au (three layers) is deposited on the laser device's bottom ohmic contact, typically comprising Ge. Then, during bonding, the solder layer is brought into physical contact with the laser device's metallization under enough heat and pressure, followed by cooling, to form a permanent joint between them. The thickness of the solder layer is advantageously less than approximately 5 .mu.m. The wetting layer is preferably the intermetallic compound Ni.sub.3 Sn.sub.4, and the auxiliary layer is formed by codepositing the metallic components of this intermetallic together with the barrier metal.
摘要:
One or more metallized chip terminals of an electronic device, such as an integrated circuit chip or a laser chip, in one embodiment are temporarily bonded to one or more metallized substrate pads of a wiring substrate, as for the purpose of electrically testing the electronic device. The composition of the metallized chip terminals is suitably different from that of the metallized substrate pads. The pads and terminals are aligned and electrically connected together with a solder located between them under pressure and a temperature above the melting point of the solder. The solder is cooled, and electrical tests of the electronic device are performed by means of electrical access from testing circuitry to the chip terminals through the substrate pads. Then the solder is heated again above its melting point while being immersed in a liquid flux, whereby the liquid solder wets the metallized chip terminals but not the metallized substrate pads, and the device is gently mechanically pulled away from the wiring substrate and is cooled thereafter. This substrate can thereafter be reused for testing other electronic devices that have similarly suitably metallized terminals. In another embodiment, testing can be performed or not as may be desired; and, as for the purpose of chip operation as an integrated circuit or laser, the chip can be allowed to remain permanently bonded to the substrate in the form of a heat-sinking or heat-spreading submount, or it can be allowed to remain only temporarily bonded to the submount and subsequently pulled away from the submount for the purpose of reuse of the submount for another chip.
摘要:
A device such as a laser is bonded to a submount such as diamond by a process in which the submount is successively coated with an adhesion layer such as titanium, a barrier layer such as nickel, and a gold-tin solder-metallization composite layer formed by sequential deposition on the barrier layer a number (preferably greater than seven) of multiple alternating layers of gold and tin, the last layer being gold having a thickness that is equal to approximately one-half or less than the thickness of the (next-to-last) tin layer that it contacts immediately beneath it. The bonding is performed under applied heat that is sufficient to melt the solder-metallization composite layer. Prior to the bonding, (in addition to the submount) the device advantageously is coated with gold and optionally with a similar gold-tin solder-metallization composite layer, at least at locations where it comes in contact with the gold-tin solder-metallization composite layer.
摘要:
A method for bonding one body to another, such as a laser device to a submount, uses a metallic layer composed of a Group VB metal, such as niobium, sandwiched between a non-metallic layer and solder layer formed by an approximate Au-Sn eutectic layer. Advantageously the Group VB layer is formed at a submount temperature of less than approximately 201.degree. C., advantageously less than approximately 125.degree. C., and preferably less than approximately 101.degree. C.--advantageously to a thickness in the approximate range 0.05 .mu.m to 0.2 .mu.m, or even thinner if pinholes do not develop. The non-metallic layer is located on one of the bodies, and the other body has a metallic coating advantageously capped with an Au layer.
摘要:
In wafer-scale-integrated assemblies, microminiature transmission lines are utilized as interconnects on the wafer. The extremely small cross-sectional area of a typical such line results in its total line resistance being relatively large. Such a line exhibits signal reflections and resonances. In practice, it is not feasible to eliminate these effects by conventional load termination techniques. As a result, the frequency at which digital signals can be transmitted over such a line is typically limited to well below its so-called resonance limit. In accordance with a feature of the invention, the structural parameters of each line are selected to meet specified design criteria that ensure optimal high-frequency performance of the line.
摘要:
In accordance with the present invention, an integrated circuit package comprises a thermally conductive plate for receiving an integrated circuit and an open rectangular structure of conductor and insulator for surrounding the sides of the circuit and presenting one or more linear arrays of conductive connectors extending laterally through the rectangular structure. Preferably the rectangular structure also includes transverse contacts. Advantageously the plate includes extensions beyond the rectangular structure for acting as cooling fins on opposing sides of the rectangular structure. The linear arrays and cooling fins are preferably on different pairs of parallel sides.
摘要:
A precisely aligned optical fiber switch assembly. A base member has a vee groove for supporting a fixed optical fiber and a second optical fiber in optical alignment with the fixed fiber. The groove contains sections of different dimensions that receive and align sheathed portions of the fibers and groove sections that receive and align unsheathed portions of the fibers. First aligning means on the base member longitudinally position the fixed and second fibers in the groove. Covering means mate with the base member for covering at least part of the sheathed portions of the fibers. Aligning means position the covering means precisely with respect to the base member.
摘要:
An m-input/n-output (e.g., 2.times.2) optical fiber switch is disclosed which alters the location of the fibers by the application of an external force. Illustratively, the switch uses a housing with a diamond-shaped opening extending therethrough, with pairs of optical fibers positioned in orthogonally located V-grooves. Upon the application of an external force, the fibers are moved into the remaining, vacant V-grooves formed by the diamond-shaped opening. In a preferred embodiment, a (2.times.2) switch is magnetically activated.
摘要:
A given testing substrate for fast-testing many integrated-circuit electronic devices, one after the other, has a set of mutually insulated collated wiring areas that can be aligned with solder-bump I/O pads of the electronic devices. At the surface of each of the corrugated areas is located a layer that is an electrically conductive durable oxide, or that is itself durable, electrically conductive, and non-oxidizable. During testing, the solder-bump I/O pads of the electronic device being tested are aligned with and pressed against the corrugated wiring areas of the given substrate. Alternatively, the electronic devices being of the electrically programmable variety, such as EPROMs, programming voltages can be delivered to each of the devices, one after the other, through the corrugated wiring areas of a single substrate.
摘要:
In the interest of enhanced yield in the manufacture of "wafer-scale" integrated circuits an assembly of integrated circuit chips is made by placing chips on a substrate. Chips have beveled edges as produced by crystallographically anisotropic chemical etching, and the substrate has wells, grooves, or openings having sloping walls. Chips are positioned on the substrate by bringing sloping walls and beveled edges in juxtaposition, and circuitry on chips is connected to circuitry on the substrate.