Actuator – sensor technology on “electronic grade” diamond films

 Thermal microheaters as used for example in thermal ink print heads contain a variety of materials, the heater itself is commonly based on refractory metals. Here, a novel concept based on diamond as a multifunctional material is proposed and demonstrated. In this concept, diamond serves as an insulating substrate, a metal-like heater and as a temperature sensor. Superheating of water could be achieved after 7.5 μs heating of a 60×60 μm element. Bubble nucleation was visualized using a high speed stroboscopic technique. The influence of the diamond thermal properties and geometry on the thermal response were investigated by dynamic 3D-simulations. Received: 29 June 1997 / Accepted: 12 November 1997