Cryogenic transimpedance amplifier for micromechanical capacitive sensors

D. ANTONIO; H. PASTORIZA; P. JULIÁN; P. MANDOLESI

REVIEW OF SCIENTIFIC INSTRUMENTS

AMER INST PHYSICS

Año: 2008 vol. 79 p. 84703 - 84703

0034-6748

We developed a cryogenic transimpedance amplifier that works at a broad range of temperatures, from room temperature down to 4 K. The device was realized with a standard complementary metal oxide semiconductor 1.5  µm process. Measurements of current-voltage characteristics, open-loop gain, input referred noise current, and power consumption are presented as a function of temperature. The transimpedance amplifier has been successfully applied to sense the motion of a polysilicon micromechanical oscillator at low temperatures. The whole device is intended to serve as a magnetometer for microscopic superconducting samples.