Abstract: An IR radiator element (1) suitable for use as a miniature infrared emitter (micro-hotplate) in a gas sensor, IR-spectrometer or electron microscope. The micro-hotplate comprises a plate (2) supported by multiple support arms (4). The plate and arms are fabricated as a MEMS device comprising a single contiguous piece of electrically-conducting refractory ceramic such as hafnium carbide (HfC) or tantalum hafnium carbide (TaHfC). Each of the arms (4), in addition to providing structural cantilever support for the plate (2), acts as a heating element for the plate (2). The plate (2) is heated by applying a voltage across the arms (4). The arms (4) may also be shaped to absorb thermomechanical stress which arises during the heating and cooling of the arms and plate. The plate, which may have an area of less than 0.05 mm2 and a thickness of between 1% and 10% of the largest dimension of the plate (2), for example, can be heated to 4,000 K or more and cooled again with a duty cycle of as little 0.
Abstract: An IR radiator element suitable for use as a miniature infrared emitter (micro-hotplate) in a gas sensor, IR-spectrometer or electron microscope. The micro-hotplate comprises a plate supported by multiple support arms. The plate and arms are fabricated as a MEMS device comprising a single contiguous piece of electrically-conducting refractory ceramic such as hafnium carbide (HfC) or tantalum hafnium carbide (TaHfC). Each of the arms, in addition to providing structural cantilever support for the plate (2), acts as a heating element for the plate. The plate is heated by applying a voltage across the arms. The arms may also be shaped to absorb thermomechanical stress which arises during the heating and cooling of the arms and plate. The plate, which may have an area of less than 0.05 mm2 and a thickness of between 1% and 10% of the largest dimension of the plate, for example, can be heated to 4,000 K or more and cooled again with a duty cycle of as little 0.