Sensors for wearable electronics

A sensor comprising:

• a first deposition of silver ink on a substrate with an inkjet material printer at room temperature,
• a second deposition of silver ink on the substrate with the inkjet material printer at room temperature, wherein the first deposition and second deposition comprise a silver based interdigital electrode,
• a carbon black film deposited on the silver based interdigital electrode, and
• at least two terminals,
• wherein a finger spacing of the interdigital electrode is between 0.1 mm and 0.3 mm,
• wherein said sensor comprises a temperature sensor,
• wherein said temperature sensor comprises a wearable temperature sensor for real-time measurement of skin surface temperature or deep body temperature,
• wherein the substrate comprises a substrate of said wearable temperature sensor, and wherein the substrate comprises a non-planar substrate,
• wherein said non-planar substrate comprises a facial mask.