Abstract: A burn-in oven is provided with a plurality of spaced, stacked burn-in-boards, each with a plurality of individual circuits being tested under heated conditions, and a plurality of valve trays positioned between two burn-in-boards to form a heat exchange compartment below the valve tray. Each valve tray has a plenum formed above it to provide a separate chamber that is a source of cooling air. Each valve tray has a plurality of valves, one over each of a number openings in the tray. Each opening overlies an integrated circuits or device under test on the burn-in-board below the valve tray. The valves control the flow of air for cooling the integrated circuits. The flow of air through the valves is the only path for cooling airflow to the integrated circuits on the burn-in-boards.

Abstract: A burn-in oven is provided with a plurality of spaced, stacked burn-in-boards, each with a plurality of individual circuits being tested under heated conditions, and a plurality of valve trays positioned between two burn-in-boards to form a heat exchange compartment below the valve tray. Each valve tray has a plenum formed above it to provide a separate chamber that is a source of cooling air. Each valve tray has a plurality of valves, one over each of a number openings in the tray. Each opening overlies an integrated circuits or device under test on the burn-in-board below the valve tray. The valves control the flow of air for cooling the integrated circuits. The flow of air through the valves is the only path for cooling airflow to the integrated circuits on the burn-in-boards.

Abstract: A heat exchange system that can accommodate a high power integrated circuit chip for burn-in temperature stressing includes a heat sink having a chip engaging surface that is adapted to engage a surface of the chip. A liquid layer fills a heat exchange gap between the surface of the chip and the chip engaging surface of the heat sink. The liquid layer provides a low thermal resistance juncture between the chip engaging surface of the heat sink and the surface of the chip, which allows for greater heat transfer therebetween.

Abstract: A burn-in oven is provided with a wall that has a number of vertically stacked, laterally extending slots aligned with each of the burn-in-board supports in the oven. When a burn-in-board is placed in the oven on the supports, an edge portion of the burn-in-board extends through a slot into a connector area. Each of the slots has a shutter associated therewith that will move from an open position to permit the burn-in-board connector portion to extend through the slot, to a closed position wherein the shutter covers the slot. A cam operator moves the shutters to a closed position, except when a burn-in-board is extending through a particular slot, it will support the shutter in its open position and the shutter will not be moved by the cam. All the shutters associated with openings through which no burn-in-board connector portion extends will be closed to prevent air flow from the burn-in oven.

Abstract: A heat exchange system that can accommodate a high power integrated circuit chip for burn-in temperature stressing includes a heat sink having a chip engaging surface that is adapted to engage a surface of the chip. A liquid layer fills a heat exchange gap between the surface of the chip and the chip engaging surface of the heat sink. The liquid layer provides a low thermal resistance juncture between the chip engaging surface of the heat sink and the surface of the chip, which allows for greater heat transfer therebetween.

Abstract: The burn-in oven is provided with a plurality of chambers, and each of the chambers has a number of stacked burn-in boards carrying devices under test. Each burn-in board is associated with an overlying fan board. The fan board divides the space between the burn-in boards so that a duct is formed on a side of the fan board opposite from its associated burn-in board. The fan boards are spaced from the burn-in boards, so that there is a space overlying the devices under tests as well. Each of the fan boards has an individual fan associated with each underlying device under test, to provide air flow through an opening directly onto the device under test. The space between each burn-in board and its associated fan board is sealed with seal plates at opposite ends of the space, and at least one of the seal plates having an adjustable damper for providing a bleed flow of cooling air through the space.

Abstract: A heat sink is used for thermally controlling a chip on a burn-in board which is being tested in a burn-in oven. The heat sink includes a resiliently mounted block that will engage a chip under resilient pressure and which is housed in a separate cup that permits accommodating misalignments or shifting of the heat sink when it contacts the chip. Additionally, the block carries a temperature sensor that is resiliently loaded against a chip which the heat sink engages. A bore mounts the temperature sensor and is also connected to a source of helium to provide a layer of helium between a surface of the heat sink and the adjacent surface of the chip for modifying the thermal coupling between the heat sink and the chip.

Abstract: An automatic loading and unloading support for use on the interior of a burn-in oven includes a frame that supports a rack of printed circuit burn-in boards connected to connectors along edges of the burn-in boards at one end of the rack. The frame has a track for supporting the rack for movement from an open end toward a closed end of the oven. Driver/receiver boards are mounted at the closed end and have connectors aligning with the connectors on the burn-in boards on a rack. When the rack is moved to a position closely adjacent to the driver/receiver board connectors, alignment pins will align the rack properly and then actuators are used for moving inserter bars that press against the back side of the rack and push the connectors on the burn-in boards into the connectors on the driver/receiver boards.

Abstract: A temperature control system for high power burn-in of integrated circuit chips which includes an individual heat sink at each of the integrated circuit chips to dissipate heat generated by the integrated circuit. A heater for each chip is provided and is temperature controlled so that heat may be added by the heater as a function of the heat generated by the integrated circuit chip. A temperature sensor is provided in close thermal contact with the integrated circuit chip to sense the temperature of the integrated circuit chip. A closed loop temperature controller is used to vary the amount of current provided to the heater to maintain a desired range of temperature. Thermal contact between the temperature sensor and the integrated circuit chips is insured by utilizing a spring to urge the sensor toward the integrated circuit chip.

Abstract: The present invention is directed to an apparatus suitable for regulating, with an impinging flow of gas, the temperature of an electronic component under thermal stress testing at selected temperatures. The apparatus comprises a sensor which senses the temperature of the electronic component and provides an electrical signal representative of sensed temperature to a controller. A gas flow regulator is used to control flow directed to impinge the flow of gas upon the electronic component as necessary to adjust the temperature. The gas flow regulator ms controlled by the controller which operates the regulator so as to adjust the temperature of the electronic components.

Abstract: A thermal control system for use with a burn-in system, the thermal control system capable of delivering a thermally preconditioned liquid to a plurality of semiconductor devices during burn-in. The thermal control system comprises a liquid reservoir containing a liquid, a pump, and a plurality of spray nozzle arrays. The liquid contained in the liquid reservoir is thermally preconditioned through the use of a heating element and a cooling element and the temperature of the liquid provided to each spray nozzle array is individually controlled through the use of a pipe heating element. The liquid is collected and returned to the liquid reservoir after being sprayed on the semiconductor devices.

Abstract: A thermal control system for use with a burn-in system, the thermal control system capable of delivering a thermally preconditioned liquid to a plurality of semiconductor devices during burn-in. The thermal control system comprises a liquid reservoir containing a liquid, a pump, and a plurality of spray nozzle arrays. The liquid contained in the liquid reservoir is thermally preconditioned through the use of a heating element and a cooling element and the temperature of the liquid provided to each spray nozzle array is individually controlled through the use of a pipe heating element. The liquid is collected and returned to the liquid reservoir after being sprayed on the semiconductor devices.

Abstract: An interconnection system for electrically connecting a burn-in board with one or more driver/receiver boards in a burn-in system. The interconnection system comprises a burn-in board located in an environmental test chamber, a first driver/receiver board having a first edge connector at a first end and a second driver/receiver board having a second edge connector at a first end. The first and second edge connectors are double density edge connectors having a slot into which the burn-in board can be inserted. A plurality of control components are mounted on the first driver/receiver board and the second driver/receiver board to provide test signals or stimuli for exercising electronic circuit components on the burn-in board. The burn-in board has a plurality of sockets thereon for insertion of the electronic circuit components.

Abstract: A method for the construction of a high density electrical connector for connecting a printed circuit board with a burn-in board in a burn-in system. The method comprises the steps of attaching a standard edge connector to a printed circuit board to form a first set of contacts, attaching two outer contact strips to the printed circuit board to form a second set of contacts, and enclosing the outer contact strips and the edge connector in an outer housing. The edge connector and the outer contact strips are secured to the printed circuit board through soldering. A burn-in board having a plurality of contact pads thereon can be inserted into the electrical connector such that the contact pads come into contact with the first and second set of contacts.

Abstract: A pair of mother burn-in boards are placed back to back, and are adequately supported with respect to each other to form an assembly. Each of the boards supports a nose board or connector board so that two sets of connectors are available for conductors and sockets on the exposed sides of the mother boards. The conductors on the two burn-in boards are connected in parallel to permit using test signals from each connector on the nose board for a socket on each of the mother burn-in boards. The assembly is made to be rigid, reliable, and to provide a wide ability to adapt components for mounting on available standard burn-in socket packages to increase the number of components that can be simultaneously tested.

Abstract: A rear module wall before a burn-in system that provides burn-in boards for electronic components to permit passing connections through slots while maintaining a good heat seal. The module rear wall is a sandwich type construction of a plurality of layers with insulating silicon rubber sandwiched between slotted backing sheets to provide for double insulation for the boards as then are slid through the slots from the interior of the oven into a tempered zone or to the exterior where they are connected to driver receiver boards and other connections.

Abstract: A burn-in board construction mounts and provides operational signals to circuit packages, for example, digital devices in an environmental stress operation such as in an oven/chamber for dynamic burn-in. Each of the circuit packages has connections to circuits and which connections are connected to conductors on the burn-in board. At least one auxiliary board is mounted on a main burn-in board and carries contacts to double the number of test connections for digital devices on such burn-in board without changing the basic mounting or environmental chamber construction. The construction permits two 128 pin driver/receiver boards of standard design to be connected to each burn-in board module. This permits coupling several hundred driver connections to a single burn-in board while still utilizing standard connectors as the interconnects.

Abstract: A method of and apparatus for bending a flat sheet of glass to a relatively sharp angle. The apparatus includes a sectionalized, gravity mold structure provided with means for delivering electrical power to electrically conducting lines formed on the sheet supported on the mold apparatus and which lead to an electrically conductive path also formed on the sheet along a line about which it is desired to bend the sheet. Opposed electrical conductors, which also serve as locator stops, are biased into engagement with portions of the conducting lines to assure continuous current flow thereto during the bending and movement of the sheet into its desired configuration.

Abstract: A method of and apparatus for bending glass sheets between press members provided with opposed shaping rails having complemental surfaces for imparting the desired curvature to a heated glass sheet. Each of the press members is provided with a plurality of burners for directing localized heat to selective portions of the glass sheet during the bending thereof to condition the sheet for subsequent tempering.