This research is concerned with the design and realization of 0.1 Um gate-length modulation-doped field-effect transistors (MODFET's) for signal amplification above 100 GHz. The research to be carried out at PSU will involve device structural design dictated by the desired mm- wave performance, and electrical measurements and characterization of completed devices. The task of device fabrication will be undertaken by the G.E. Electronics Laboratory, Syracuse, NY, and test samples will be made available to the PI for studies at no additional costs to NSF. The research would examine the quality of the pseudomorphic InGaAs, and the associated heterostructure layers in the proposed n- AlGaAs/InGaAs/GaAs MODFET structure. A low Al-molefraction in the Si- doped AlGaAs has been very effective in reducing the deep DX centers that usually cause the well known I-V collapse in the conventional n- AlGaAs/GaAs MODFET's. The high performance of the 0.25 Um gate-length pseudomorphic MODFET's studied under the current project has been main motivation to the proposed 0.1 Um gate-length MODFET structure which is expected to provide useful power gain in the 100 to 200 GHz range. The proposed research recognized the importance of optimized materials growth for the desired MODFET structure, and a thorough investigation of the material and device electrical properties in order to achieve a better understanding of the device operation.
