摘要:
Deformation of a lifting ring of bimetallic structure or memory metal is matched to a solder softening or melting temperature to apply forces to lift a chip from a supporting structure, such as a substrate or multi-chip module, only when the solder connections between the chip and the supporting structure are softened or melted. The temperature of the chip, module and solder connections there between is achieved in a commercially available box oven or belt furnace or the like and results in much reduced internal chip temperatures and thermal gradients within the chip as compared to known hot chip removal processes. Tensile and/or shear forces at solder connections and chip and substrate contacts are much reduced in comparison with known cold chip removal processes. Accordingly, the process is repeatable at will without significant damage to or alteration of electrical characteristics of the chip or substrate.
摘要:
A cost efficient, highly reliable method to remove electronic devices and components from substrates eliminates separate tooling for every substrate and device or component size. The apparatus which implements the method allows for multiple device or component removal simultaneously, or in a single sequential operation, in a nondestructive action in a very low cost environment. A box oven and vacuum system and is used with different device or component and substrate sizes providing a simple, low cost, molten device removal procedure, eliminating the need for thermal monitor build and associated profiling for each product. The apparatus works independently of chip type or size, utilizing universal fixturing, and can be set up to pull multiple devices and/or components in a single run.
摘要:
A porous metal block for selectively removing solder or braze from a substrate is disclosed. The block comprises a plurality of protrusions which absorb solder or braze through capillary action. The number and dimensions of the protrusions vary depending on the application. Also disclosed is a process for making such a block involving a unique two steps sintering process.
摘要:
A porous metal block for selectively removing solder or braze from a substrate is disclosed. The block comprises a plurality of protrusions which absorb solder or braze through capillary action. The number and dimensions of the protrusions vary depending on the application. Also disclosed is a process for making such a block involving a unique two steps sintering process.