Study of tunneling noise using surface micromachined tunneling tip devices

摘要

This paper reports the measurement and theoretical analysis of noise in surface micromachined tunneling tip devices. The devices are fabricated using the surface micromachining technology. The bending beams and proof masses are formed by electroplating of nickel and gold. The tips are made by plating metal on the partially etched sacrificial layer. Noise spectra are obtained and compared for different electrode materials and different operating pressures. The results show that 1/f noise dominates in the low frequency region and the 1/f noise level in the vacuum is lower than that in air ambient. A mathematical model is established to simulate the 1/f noise related to surface adsorption-desorption process.