We have developed an electromagnetic field intensity distribution measurement system. In this system, a very small temperature change distribution on the electromagnetic absorption screen is measured using an infrared camera. It is expected that this system will be very useful for the evaluation of the electromagnetic fields around electric devices. In this paper, a measurement of the electromagnetic field intensity distribution near an AC–DC converter is described. We could get a 3-D image of the electromagnetic field intensity distribution as a temperature change distribution on the screen. Furthermore, by measuring the near field of a micro strip line and a high frequency balance filter, the enhanced electromagnetic fields near these devices were clearly observed.

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The commonly used electroless plated Ni(P) diffusion barrier is prone to react rapidly with Au–Ge eutectic solder to form NiGe, Ni₅Ge₃ and Ni₃P intermetalics (IMC) at the solder/Ni(P) interface after aging at 330°C. The rapid growth of the Ni–Ge intermetalics and the subsequent oxidation of the Cu circuit path under the Ni(P) layer seriously degrade the joint of the Au–Ge solder/Ni(P) interface. To improve joint reliability, a 200 nm-thick Ni(P)/Ta/TaN/Ta diffusion barrier (DB) was prepared on the Ni(P) layer using a sputter process. SiC Schottky Barrier Diode (SBD) power devices were die bonded on the substrate with the Ni(P)/Ta/TaN/Ta DB in a vacuum reflow system. The bonded samples were aged at 330°C in air. After 1,000 hrs, little change in the bond strength of the SiC–SBD was observed. Little reaction between the Ni(P)/Ta/TaN/Ta DB and the Au–Ge solder was observed by transmission electron microscopy (TEM). The Ni(P)/Ta/TaN/Ta DB adheres well to the Ni(P) layer after a thermal cycling test of 1,079 cycles in the temperature range of −40–300°C.

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In this paper, we examined the effectiveness of multi-valued transmission as a crosstalk reduction technique. In multi-value transmission, 4-value transmission is the most effective for crosstalk reduction. In addition, using a S-G-S micro-strip line that set up a grand line between single lines showed clearly that crosstalk reduction is possible, without decreasing the slew rate.

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