US Patent Application 20100066451 - Compound semiconductor device and doherty amplifier using compound semiconductor device
InventorsAssigneeUS Classes330/277, Including field effect transistor257/191, Having graded composition257/E29.246With two-dimensional charge carrier gas channel (e.g., HEMT; with two-dimensional charge-carrier layer formed at heterojunction interface) (EPO)Attorney, Agent or FirmForeign Documents
International ClassesH03F 3/16H01L 29/778 Issued Patent Number:7777251Abstract textA lower electron supply layer is disposed over a lower electron transport layer made of compound semiconductor. The lower electron supply layer is made of n-type compound semiconductor having an electron affinity smaller than that of the lower electron transport layer. An upper electron transport layer is disposed over the lower electron supply layer. The upper electron transport layer is made of compound semiconductor having a doping concentration lower than that of the lower electron supply layer or non-doped compound semiconductor. An upper electron supply layer is disposed over the upper electron transport layer. The upper electron supply layer is made of n-type compound semiconductor having an electron affinity smaller than that of the upper electron transport layer. A source and drain electrodes are disposed over the upper electron supply layer. A gate electrode is disposed over the upper electron supply layer between the source and drain electrodes. |
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