This study presents a detailed experimental investigation of the combined effects of pressure and subcooling on nucleate pool boiling and critical heat flux (CHF) for degassed fluorocarbon FC-72 boiling on a plastic pin-grid-array (PPGA) chip package. In these experiments pressure was varied between 101.3 and 303.9 kPa and the subcooling ranged from 0 to 65°C. As expected, lower wall superheats resulted from increases in pressure, while subcooling had a minimal effect on fully developed pool boiling. However, the superheat reductions and CHF enhancements were found to be smaller than those predicted by existing models. The CHF for saturated liquid conditions increased by nearly 17 percent for an increase in pressure from 101.3 to 202.7 kPa. In experiments with both FC-72 and FC-87 further increases in pressure did not produce any significant increase in CHF. At a pressure of 101.3 kPa a subcooling of 30°C increased CHF on horizontal upward-facing chips by approximately 50 percent, as compared to 70 percent on vertically oriented packages. The enhancement in CHF due to subcooling decreased rapidly with increasing pressure, and the data showed that the influence of pressure and subcooling on CHF is not additive. A correlation to predict pool boiling CHF under the combined effects of pressure and subcooling is proposed.

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The paper presents a novel approach improve MEMS reliability even during new devices. Firstly, the shock i mechanisms of breakage and stiction are test structures. The obtained results in ter rated loads are compared to acting loads mechanical shock, which are calculated impact model. The model is based superposition approach and can be app designs. It accounts for impacts at flex including stiction as well as for deflections leading to strongly non damping.

The early effort of MEMS sensor development was focused mainly on the transducer: designing and manufacturing a mechanical device that could convert a physical input into an electrical signal using traditional semiconductor processes. With the rapid advancement in MEMS technologies, MEMS packaging is becoming increasingly critical and plays a major role in the successful commercialization of a MEMS product. Freescale has adopted the philosophy [1–2] of concurrent transducer and package designs to facilitate the rapid introduction of sensor products into the market. This paper presents a sub-modeling procedure that allows the modeling and simulation of a transducer and a package seamless at the same time.

This study presents a detailed experimental investigation of the combined effects of pressure and subcooling on nucleate pool boiling and critical heat flux (CHF) for degassed fluorocarbon FC-72 boiling on a plastic-pin-grid-array (PPGA) chip package. In these experiments, pressure was varied between 101.3 and 303.9 Wa., and the subcooling ranged from 0 to 65 C. As expected, lower wall superheats resulted from increases in pressure, while subcooling had a minimal effect on fully-developed pool boiling. However, the superheat reductions and CHF enhancements were found to be smaller than those predicted by existing models. The saturation CHF increased by nearly 17% for an increase in pressure from 101.3 to 202.7 Wa. In experiments with both FC-72 and FC-87, further increases in pressure did not produce any significant increase in CHF.At a pressure of 101.3 kPa, a subcooling of 30 C increased CHF on horizontal, upward-facing chips by approximately 50% as compared to 70% on vertically oriented packages. The enhancement in CHF due to subcooling decreased rapidly with increasing pressure and the data showed that the influence of pressure and subcooling on CHF is not additive. A correlation to predictepool boiling CHF under the combined effects of pressure and subcooling is proposed.