Low-frequency noise in AlSb/InAs and AlSb/InAsSb HEMTs

Measurements of the low-frequency noise in AlSb/InAs and AlSb/InAsSb HEMTs are reported. At room temperature, the slope of the noise level for a basic InAs-channel device is very close to ideal 1/f. A more advanced version of this device and the device with the InAsSb channel display a significant generation-recombination component. The Hooge parameter, /spl alpha//sub H/, for all the devices is in the range between 10/sup -3/ and 10/sup -2/ based on floating-gate measurements at low drain voltage. At lower temperatures, larger G-R components appear in all devices and move with temperature, indicating the presence of discrete trap levels. These noise Lorentzians become more prominent when the devices are exposed to visible light, and move up in frequency with increasing electric field.