摘要:
A melt recharge method is disclosed which uses a self-actuated charge container open at one end except for deformable support members which are positioned to support the charge material. The support members are formed of a material which has sufficient rigidity at room temperature to support the charge material but which when heated above its annealing temperature loses its rigidity and can no longer support the charge material which therefore falls into the existing melt. Upon cooling, the support members regain their rigidity and can be reformed for reuse.
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:
A self-actuated charge container is open at one end except for deformable support members which are positioned to support the charge material. The support members are formed of a material which has sufficient rigidity at room temperature to support the charge material but which when heated above its annealing temperature loses its rigidity and can no longer support the charge material which therefore falls into the existing melt. Upon cooling, the support members regain their rigidity and can be reformed for reuse.
摘要:
Wire bonding is eliminated in the assembly of microelectronic devices, by a process involving the direct bonding of circuit electrodes to a metallic sheet-frame member having a plurality of inwardly extending leads. A single-step bonding technique is employed for the simultaneous bonding of all leads to a semiconductor integrated circuit chip. Lateral confinement of the lead frame member during the bonding steps causes a buckling action in the lead fingers, 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.