Low-frequency characteristics of a thin-film multijunction thermal converter under vacuum

We have evaluated the AC-DC transfer differences of our thin-film multijunction thermal converters with increased heat capacity under vacuum conditions to improve the low frequency characteristics. μμ The measured thermal time constant at about 0.001 Pa is increased up to 9 s from 3 s measured at ambient pressure. The AC-DC transfer differences evaluated by using a sampling method are less than 1 μV/V down to 10 Hz, and 10 μV/V down to 0.2 Hz, which is about ten times smaller compared with those obtained at ambient pressure.