摘要
In this paper, a zero-bias mixer using a lateral fieldeffect diode fabricated on standard GaN-on-Si AlGaN/GaN highelectron- mobility-transistor wafers is demonstrated. The diode features strong nonlinearity near zero bias, enabled by a threshold-voltage modulation using a fluorine-plasma-treatment technique. The maximum change in conductance was adjusted to ~0 V, leading to optimal conversion loss (CL) of the mixer at zero bias and eliminating the need for any dc supplies. The mixer is characterized from room temperature (RT) to 250 ?C. At 2.5 GHz and at RT, the CL and third-order intermodulation intercept point are 12.9 dB and 17.64 dBm, respectively. The operation of the proposed diode is modeled by a physical equivalent circuit, with the element values extracted from the measured S-parameters. The voltage-biasing dependence of the CL can be explained by the model. The high-temperature operation of the mixer shows that the proposedmixer can perform well in high-temperature and ultralow-power applications. © 2009 IEEE.