Abstract: A method and apparatus for separating a semiconductor device from a substrate in a fixture with a shearing element, wherein the semiconductor device is attached to the substrate by solder connections to form an assembly, includes using the shearing element to apply a loading force to the semiconductor device. The assembly of the substrate and the semiconductor device are loaded into the fixture with the shearing element proximate the semiconductor device, and heating the solder connections of the assembly in the fixture are heated proximate the substrate to a predetermined temperature by applying a heat source to a surface of the substrate distal from the semiconductor device.

Abstract: A method and apparatus for separating a semiconductor device from a substrate in a fixture with a shearing element, wherein the semiconductor device is attached to the substrate by solder connections to form an assembly, includes using the shearing element to apply a loading force to the semiconductor device. The assembly of the substrate and the semiconductor device are loaded into the fixture with the shearing element proximate the semiconductor device, and heating the solder connections of the assembly in the fixture are heated proximate the substrate to a predetermined temperature by applying a heat source to a surface of the substrate distal from the semiconductor device.

Abstract: Chips requiring high temperature reflow for attachment to a module substrate are attached first and then a eutectic water soluble solder paste and/or water soluble flux is dispensed on both the TSOP and the PBGA chip pads instead of using the paste screening techniques. The dispensing is done by injecting solder on the solder sites individually. Characteristics of the solder paste used is that it must be fluid enough to be injected onto the individual sites yet have enough body that it remains in place and does not run from site to site once dispensed. A paste capable of providing such characteristics is one having: a ) a very fine particle size in the range of 400 to 500 mesh and preferably between 400 and 450 mesh; b) a low viscosity (below 500 k centerpoise and preferably between 425 to 375 cps); and c) a solid content of 86% or lower and preferably between 84 and 80%.