Nippon Telegraph and Telephone Corp. (NTT) has developed a diamond semiconductor device that operates at 81 GHz frequency, more than twice the speed of earlier devices. The advance promises to make amplification in the millimeter-wave band from 30 to 300 GHz possible for the first time.

Diamond is expected to be the next- generation semiconductor material because of its high thermal conductivity, high breakdown voltage and high carrier mobility. Together, these characteristics makes diamond semiconductors most suitable for high frequency, high power devices.