HIGHLY-SENSITIVE INGAAS-2DEG HALL DEVICE MADE OF PSEUDOMORPHIC IN0.52AL0.48AS/IN0.8GA0.2AS HETEROSTRUCTURE

A monolithically integrated and highly sensitive InGaAs-2DEG Hall device with a very low temperature coefficient has been fabricated by a pseudomorphic In0.52Al0.48As/In0.8Ga0.2As heterostructure with a very high electron mobility of 16 000 cm2/V s. The product sensitivity of this Hall device is as large as 320 V/A T with a temperature coefficient of -0.035%/K and a Hooge noise parameter of 9 x 10(-4). The magnetic sensitivity, four times as large as that of an epitaxial GaAs Hall device, increases linearly with the drive current up to 40 mA, and the maximum sensitivity of 15 V/T is obtained without any amplification. The minimum magnetic fields detectable by means of this Hall device with a high S/N ratio are expected to be 2 x 10(-6) T and 6 x 10(-8) T at operating frequencies of 1 Hz and 1 kHz, respectively.