Mechanical properties of electroless copper deposits considered to be most important for printed circuit manufacturing process. In order to achieve sufficient performance level, the correlation between the mechanical properties and basic bath formulation and condition of electroless copper were studied.
Ductility was increased with increasing copper ion, formaldehyde concentration and pH value at certain level of dissolved oxygen. However, ductility was not fully correlated with occurence of corner cracking after soldering. The differences in mechanical properties of copper were caused by the differences of crystal structure and incorporated impurities and hydrogen. It was also found that high elongation copper has 1000-1800Å in grain size and low one has 700-800Å in grain size.

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Recently the crosstalk noise has come into problem according to high-density wiring of the printed circuit board. The reduction technique of the crosstalk noise by means of diode termination was described in this report.
The measurements were qualitatively confirmed by the simulation using partial element equivalent circuit model and circuit simulator. The reduction of undershoot of the wave fall-off caused by the reflection depends on the junction capacitance of the diode.
The crosstalk noise was reduced 1/3-1/2 by the termination of the active line only. The effects are the trade-off between fall-time and noise reduction.

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