Improvement of Microwave Performance for Metal-Semiconductor Field Effect Transistors Fabricated on a GaAs/Si Substrate with a Resistive Layer at GaAs Si Interface
Abstract
We report on the improvement in the microwave performance of metal-semiconductor field effect transistors (MESFETs) fabricated on GaAs/Si with a resistive layer at the GaAs-Si interface. This layer was obtained by using a p-type AlGaAs layer or an oxygen-doped AlGaAs layer grown by metal-organic chemical vapor deposition (MOCVD). Correlation between sheet carrier concentration in the resistive layer and the device performance was studied and a marked improvement was found by reducing the number of carriers in the layer to 4.1×1012 cm-2, which was about 1/5 of that for standard GaAs/Si. High cutoff frequency of22 GHz, comparable to that of MESFETs/GaAs, was obtained for0.8-µm-gate-length MESFETs/Si with a sheet carrier concentrationof 1.5×1012 cm-2. On evaluating scattering parameters for improved MESFETs/Si, it was found that the parasitic pad capacitance, characteristic for standard GaAs/Si, became as small as that for MESFETs/GaAs. These results demonstrate that GaAs/Si with a resistive layer is applicable to GaAs electronic devices.
- Publication:
-
Japanese Journal of Applied Physics
- Pub Date:
- May 1999
- DOI:
- 10.1143/JJAP.38.2704
- Bibcode:
- 1999JaJAP..38.2704A