Interfacial reactions of Ni on Si_(1-x)Ge_(x) (x=0.2, 0.3) at low temperature by rapid thermal annealing

摘要

The interfacial reaction of Ni with relaxed Si_(1-x)Ge_(x) (x=0.2,0.3) films in the low temperature range, viz., 300-500℃, has been investigated and compared with that of Ni with Si (i.e., x=0). Ni_(2)(Si_(1-x)Ge_(x)) and Ni_(3)(Si_(1-x)Ge_(x))_(2) were observed at 300℃ whereas a uniform film of Ni(Si_(1-x)Ge_(x)) was formed at 400℃ for both Si_(0.8)Ge_(0.2) and Si_(0.7)Ge_(0.3) substrates. At 500℃, a mixed layer consisting of Ni(Si_(1-y)Ge_(y)) and Si_(1-z)Ge_(z) was formed with a relation of z>x>y. Sheet resistance measurement results show that the silicided film attains its lowest value at an annealing temperature of 400℃. The approximate values of the resistivity of the corresponding uniform Ni(Si_(1-x)Ge_(x) (x=0.2,0.3) derived from the transmission electron microscope and sheet resistance results are 19 and 23 μΩ cm, respectively.