abstract |
The present invention is a silicon nitride ceramic plate having a thermal conductivity of 60 W / mk or more at 25 ° C., and an intermediate layer including oxygen and at least one element selected from the group consisting of titanium, zirconium, hafnium (Hf), niobium (Nb), and aluminum. A high thermal conductivity silicon nitride circuit board made of a metal circuit board bonded to a silicon nitride ceramic plate and a semiconductor device using the same are provided. |