Table 1: Ni layer thickness for the samples according to the evaporation time of Ni powders and without or with H2 plasma pretreatment.

SamplesEvaporation time of Ni powdersResulting Ni layer thickness5 minutes H2 plasma pretreatment

A10 sec~50 nmNone
B20 sec~80 nmNone
C40 sec~150 nmNone
D1 minute~250 nmNone
E3 minutes~350 nmNone
F1 minute~250 nmYes