Optically—Controlled InP Based Quasi-Read ATT Diode— A Novel Device at MM-Wave Window Frequency For High-Power Generation

The millimeter‐wave properties of optically controlled Quasi‐Read Double Drift InP IMPATT diodes are studied for the first time at elevated junction temperature. The study indicates that the un‐illuminated device is capable of generating a CW power of 13.0 W at 145 GHz frequency; however it reduces significantly in case of optically‐controlled devices. The optical‐illumination studies on the high frequency properties of the Top Mounted and Flip‐Chip device reveals that the photo‐generated leakage current reduces the RF power output and negative resistance of the devices along with an upward shift of operating frequency. The performances of the Quasi‐Read devices are further compared with those of its flat‐profile counterparts. It is interesting to observe that Quasi‐Read diodes are performing much better as far as RF‐power, efficiency and negative resistances are concerned. In addition to this the study indicates that Quasi‐Read diodes are much more photo‐sensitive than flat‐profile diodes. It is further interesting to note that Flip‐Chip diodes are more photo‐sensitive than Top‐Mounted diodes.