| A number of novel optoelectronic devices which have important applications in future integrated photonic and millimeter wave systems are examined. These include High Electron Mobility (HEMT) Phototransistors, High Frequency Polymer Modulators, and Traveling-Wave Heterojunction Bipolar Phototransistors (TW-HPT). To characterize these devices at millimeter wave frequencies, a frequency domain technique, optical difference frequency mixing and a time domain technique, picosecond electro-optic sampling, were employed. Both of these techniques showed characterization bandwidths greater than 200 GHz.; For the HEMT Phototransistors, optical mixing with difference frequencies to 213 GHz is reported. To the author's knowledge, this is the highest frequency optical mixing signal obtained in three terminal devices to date. A number of other important applications of optical mixing are also investigated, including a demonstration of a fiber-millimeter data link and optical generation of millimeter waves for use in spectroscopic applications. An integrated High Frequency Polymer Modulator was characterized in W-band using an optical heterodyne technique. This demonstration represents a major advance in modulator technology. Lastly, a TW-HPT was characterized from 80-110 GHz in the frequency domain. Due to its increased absorption volume, this new device, which promises to overcome the bandwidth-efficiency limitations of traditional phototransistors, showed no optical saturation effects up to 50 mA of photocurrent at 60 GHz.; As a means of integrating these devices into useful systems, the Epitaxial Lift-off (ELO) technique was examined. ELO is a versatile technique which allows devices made from vastly different material systems to be integrated into monolithic circuits. Experiments to 140 GHz were conducted on HEMT Photodetectors to determine the effects of ELO on the millimeter wave response. It was found that performing ELO on the devices had minimal impact on the performance. This is an encouraging result which validates the use of ELO for integration of high frequency devices. To improve the bonding of ELO devices to host substrates, a new technique which uses Self-Assembled Monolayers (SAMs) to improve attachment strength and yield was investigated. |
