Microwave detector diodes based on InGaAs/AlGaAs/GaAs heterostructures

An original low-barrier diode n+-InGaAs/AlGaAs/n+-GaAs heterostructure was developed and grown by metalorganic vapor phase epitaxy. Growth conditions are practically the same as were used in standard pseudomorphic high-electron-mobility transistor technology. Test diodes were made on the basis of the heterostructure and their transport properties were studied. For comparison with experimental results, the transport characteristics of diodes were simulated in the framework of the combined thermionic-emission/diffusion theory. A useful method for the microwave measurements of diodes on a wafer was employed, which allows one to determine all the main parameters of the equivalent diode circuit and their detection characteristics. The diodes have a high quadratic nonlinearity parameter value (> 20 V−1) and small specific values of differential resistance (10−4 Ω cm2) and capacitance (10−7 F/cm2) at zero bias. The prospects of using the developed heterostructure to create highly sensitive microwave radiation detectors are shown.