摘要:
A semiconductor device in which a conducting shielding member is disposed over the space between the input and output terminal metal layers and over the semiconductor chip bonded to the output metal layer. The shielding member is electrically connected to the common terminal metal layer. This construction results in a reduction in the storage capacitance between the input and output terminal layers and improved power gain and stability of operation, particularly at high frequencies.
摘要:
This disclosure relates to the packaging of microwave integrated circuits (MICs) whereby an MIC is hermetically sealed within an enclosure comprising a first plate of dielectric material which carries the circuit to be enclosed, a wall of dielectric material sealed to the surface of the first plate surrounding the circuit, and a second plate of dielectric material providing a lid sealed over the wall to complete the enclosure. The first plate carries planar conductors which define at least one microwave transmission line, e.g. microstrip, extending across the wall into the enclosure from outside to provide direct microwave coupling to the enclosed circuit and thereby obviating the usual need for transitions to and from coaxial cable.Part or all of the enclosed circuit may be contained within a recess provided by forming an aperture in the first plate and sealing a third plate of dielectric material across the aperture from below.The disclosure describes various techniques for reducing losses where the transmission line propagation paths traverse the wall on the surface of the first plate. The entire package may be fabricated using materials and techniques compatible with those used in fabricating MIC's, for example thick film.
摘要:
Disclosed is a semiconductor body mounted on an electrically-insulative, thermally-conductive plate which also carries metallized contacts electrically connected to the various contact areas associated with the semiconductor body. A protective one-piece insulative bridge overlies the semiconductor body and includes legs secured to the plate and a cross member extending over the body. The bridge facilitates pressing or clamping the plate in enhanced heat-transferring relation to a substrate heatsink without application of any pressure on the body or other deleterious effects to the body.
摘要:
A lead structure formed from a sheet of electrically conducting material having a plurality of spaced integral lead arrays formed therein with each of the arrays comprising a plurality of first leads formed from the sheet material in one region thereof and being integral with the sheet with each of the leads being cantilevered and having inner extremities which are free and positioned in a predetermined pattern. Portions of the first leads adjacent the free ends are convoluted. A semiconductor body having at least portions of an electrical circuit formed therein and with contacts in a predetermined pattern carried by the body and lying in a common plane is secured to each of the arrays with the contact pads being bonded to the inner extemities of the first leads. A first encapsulating means is provided for encapsulating the semiconductor body and the inner extremities of the first leads with the outer extremities of the first leads being free of the first encapsulating means. After the first encapsulation, the outer extremities of the first lead are separated from the sheet of material. A plurality of spaced second leads are then secured to the outer extremities of the first leads. A second encapsulating means is then provided for encapsulating the first encapsulating means, the outer extremities of the first leads and the inner extremities of the second leads with the outer extremities of the second leads being free.
摘要:
Wire bonding is eliminated in the assembly of microelectronic devices, by a process involving the direct bonding of circuit electrodes to an unsupported metallic sheet-frame member having a plurality of inwardly extending leads. A single-step vibratory pressure welding technique is employed for the simultaneous bonding of all leads to a semiconductor integrated circuit chip. Lateral confinement of the leads during the bonding steps causes a buckling action to introduce a small but critical loop in each lead to ensure clearance between the lead fingers and the perimeter of the semiconductor chip, whereby electrical shorting is avoided. The loop also provides a structural flexibility in the leads, which tends to protect the bonding sites from excessive stresses. Subsequently, the first frame member including the bonded circuit is attached, preferably by resistance welding, to a second lead frame member of heavier gage and increased dimensions, suitable for connection with external circuitry. Excess portions of the first frame member are then removed, providing a completed assembly for packaging; e.g., plastic encapsulation or hermetic sealing, as in a ceramic-glass flat package.
摘要:
The drying characeteristics of a printing paste comprising a vehicle containing a binder and a low boiling point solvent are improved by substituting a high boiling point solvent for a portion of the low boiling point solvent without substantially adversely affecting the viscosity and flow properties of the paste. The printing paste is advantageously employed in silk screen printing in multiple passes where printed layers must have a uniform degree of wetness. The printing paste and vehicle are especially useful in the manufacture of microelectronic packages.
摘要:
In a radio frequency transistor package, a layer of metallization is deposited on an electrically insulative thermally conductive ceramic substrate member serving as a heat sink. An insular region of the metallization serves as a pad for receiving a transistor die with the collector region of the transistor bonded to the insular region of metallization. The region of the metallization surrounding the pad comprises a ground plane. An apertured ceramic insulative spacer is bonded over the ground plane metallization with the aperture in registration over the transistor. Input, output and a pair of common lead metal strips are bonded to the upper surface of the spacer in generally coplanar configuration. The two common leads extend across the spacer adjacent opposite sides of the aperture in generally tangential relation thereto. The input and output leads are disposed in between the common leads and are interrupted by the central aperture in the spacer. The common leads are electrically interconnected to the ground plane metallization layer via conductive means extending through the aperture in the spacer. The input lead is connected to one of the base or emitter regions of the transistor die via wire bonding leads extending through the aperture in the spacer. The other base or emitter region of the transistor die is connected via parallel wire bonding leads to the surrounding ground plane metallization. The output lead is connected via a set of parallel wire bond leads through the central aperture to the transistor pad.
摘要:
The external lead frame for a plastic sealed, cavity molded type semi-conductor device is formed of Phospor bronze, with the bronze lead frame liquid honed, it is pre-heated and supported in a mold cavity so as to be embedded into a powder epoxy resin molded header with improved sealing between the Phospor bronze lead frame in the header molded thereabove.
摘要:
Semi-conductor devices and other miniature circuit elements are hermetically sealed by mounting them on a peripherally metallized ceramic carrier, brazing a metal ring to carrier and brazing a ceramic cover onto the ring; the cover has also peripheral metallization, so that the hermetic seal results from metal-tometal bond. The carrier is provided with metallized apertures as electrical feed through into the space as defined by carrier, ring and cover. Metal leads are soldered to the metallization of the apertures on the outside of the carrier, while connections are made from the circuit elements to the metallization of and around the apertures in the said inside mounting space.
摘要:
A method of making a cavity molded type semiconductor device with an external lead frame is disclosed wherein the external lead frame is prepared with a liquid honing treatment prior to its being molded into a base portion after molding, and after molding, the portion of the lead frame extending into a cavity and the mating surface of the base portion are again subjected to a liquid honing treatment. The two liquid honing treatments serve to markedly increase the ability to prevent leakage of atmospheric air into the sealed cavity of the finished molded semiconductor device.