Batch fabrication and operation of GaAs-AlxGa1-x As field-effect transistor-self-electrooptic effect device (FET-SEED) smart pixel arrays

The structure, processing, and performance of arrays of integrated field-effect transistor-self-electrooptic effects devices (FET-SEEDs) consisting of doped-channel field-effect transistors, multiple quantum-well (MQW) modulators, and p-i-n MQW detectors are discussed. The performance of the FETs and SEEDs such as g_m and contrast, is equivalent to that obtained when they are made separately. Typical values are g_m=80 mS/mm and contrast of 3. The largest arrays contain 128 circuits. The circuits operate at speeds as fast as 500 Mb/s, with optical input switching energy of ≈400 fJ. At 170 Mb/s, the required optical input switching energy is ≈70 fJ. This optical energy is at least a factor of 20 less than for symmetric SEEDs (S-SEEDs) with the same optical window sizes. Hence, FET-SEEDs provide superior performance compared to conventional S-SEEDs