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In previous work for the Air Force on the Three Terminal Qptoelectronic Array program, a technology base was developed for the implementation of monolithic integrated optoelectronic circuits based upon the modulation doped inversion channel interface. In the Integrated Optical Transceiver program, that technology was adapted to the implementation of traveling wave devices that could operate at frequencies up to 100Gb/s. The concepts of a grating coupled vertical cavity laser and a grating coupled resonant cavity detector are introduced and designs were completed and implemented in photomasks. The performance of the second order grating was evaluated and models developed. The insertion of the grating into the vertical cavity waveguide was characterized and the laser performance was analyzed. A new approach to the implementation of the waveguide was developed. The speed of the detector was analyzed as a function of the velocity mismatch. A complete set of photomasks (14 levels) was developed including traveling wave devices, O/E test circuits and a variety of diagnostic test chips. The devices implemented include FET circuits-CCDs, switch based O/E interface circuits, HFET and DOES lasers as vertical emitters, directional couplers, and heterodyne laser sources.

The opto-electronic development program has moved forward substantially during the last year. In the 100GHz receiver program with Wright Patterson Air Force Base, new approaches to the implementation of high speed lasers and detectors have been devised. These structures include transmission lines with phase velocities matched to the group velocity of the optical waveguide to eliminate the limitation of the device capacitance and output impedance. A new process sequence has been developed to minimize parasitic capacitance through the use of the natural oxidation of A1 containing compounds. A phase mask technology has been implemented to produce laser gratings. A complete test mask has been produced to evaluate the traveling wave concept. The SBIR program to produce neural network building blocks with the inversion channel technology is now underway. The Inversion Channel Process technology to build these circuits is identical to the other program although the emphasis here is to produce integrated chips which are coupled by free space transmission. Measurements of the nonlinear index in the fiber of 1.8 x 10(exp -17) m(sup 2)/W have been obtained. The erbium doped fiber laser has produced stable pulse trains of 10ps pulses at data rates of 500MHz. The mode locked sources can now be used with the optical Kerr switches to realize all optical components.