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Powder injection molding process has been developed for a cost-effective fabrication of micro PZT array in diagnostic 2D array ultrasound transducer. The developed process consists six main steps; mold insert fabrication, mixing of powder and binder, injection molding, demolding of sacrificial mold insert, solvent and thermal debinding, densification of PZT ceramics. 1–3 type PZT/polymer composite fabricated by developed process shows 0.67 of electromechanical coupling property in plain mode and 0.56 in rod array mode which are 99% and 96% of reference property. Based on high productivity and shape complexity of ceramic injection molding, micro-manufacturing process for micro-scale PZT transducer has been demonstrated with according piezoelectric performance characterization.

Many thermomechanical reliability studies on microelectronics and microsystems have relied upon computational analysis, since experimental work is rather difficult and very time-consuming. For computational analysis, it is essential to use as input accurate material properties; if not, the results of a reliability analysis may be very inaccurate. However, it is still quite difficult to arrive at unified material properties for modeling microelectronic assemblies because of the absence of standards for micro-material characterization, the difference between bulk and in-situ material properties, and so forth. The goal of this study was to determine the uniaxial stress-strain curve of a solder in a flip-chip assembly, using experimental measurements and finite-element analysis (FEA) of the solder's thermal deformation characteristics with increasing temperature. The thermal deformation of flip-chip solder joints was measured by electronic speckle pattern interferometry (ESPI). For the scale of evaluation required, the measurement magnification was modified to allow its application to micromaterials by using a long-working-distance microscope, iris and zoom lens. Local deformation of solder balls could be measured at submicrometer scale, and stress-strain curves could be determined using the measured thermal deformation as input data for finite-element analysis. The procedure was applied to an Sn-36Pb-2Ag flip-chip solder joint.

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