Figure 3.

Thermocouple on a 30-nm-thick SiN-membrane. (a,b) SEM images of thermocouple made on a 250 × 250 μm² SiN window. Note, secondary (large) contact pads are made from the same metal (Au or Ni) as the smaller ones to avoid formation of a secondary thermocouple. The large contacts are placed on Si substrate to remove a thermal gradient on the thermocouple (such gradient was responsible for the observed temperature change in Fig. 2(b) measured with the Au-Au contact). (c) Temperature vs. laser power. (d) Temperature vs. position of the electron beam across the central cross section (along the line in (b)). Diameter of the e-beam was $\sim 0.5$ μm at the acceleration voltage of 25 keV; modulation frequency was 30 Hz, current $\sim 1.7$ nA as measured by Faraday cup without the sample. Central shaded region depicts the location of membrane. E-beam was scanned across the SiN window and Si substrate without direct exposure of metal leads/contacts.