MEMS Low-Magnetic Electric Heating Chip for Temperature Control of Alkali Vapor Cell

The article is devoted to solving the problem of ensuring accurate control of the operating temperature of alkali vapor cells for quantum frequency standards and magnetometers in order to increase the stability of their parameters. For this purpose, a low-magnetic electric heating chip, containing a temperature control system, which consists of a thin-film heater and a temperature sensor, has been developed and manufactured by MEMS technology. The system has such a design that the magnetic fluxes generated by the electric currents passing through its individual elements mutually extinguish each other. The heating chip and the cesium vapor MEMS cell were integrated into the physical package of the atomic clock. The magnitude of the magnetic field induced in the center of the MEMS cell was estimated by measuring of the atomic clock resonant frequency shift at different heater currents. It was found that the dependence of the parasitic magnetic flux density on the heater current has a linear character with a coefficient of 2.1 nT/mA.