Microheater

About: Microheater is a research topic. Over the lifetime, 814 publications have been published within this topic receiving 12478 citations.

Modeling and Experimental Identification of Silicon Microheater Dynamics: A Systems Approach

Abstract: Microfabricated silicon cantilevers with integrated heating elements are powerful tools for manipulation and interrogation at the nanoscale. They can be used for highly localized heating of surfaces and also serve as electrothermal probes such as topography and position sensors. A thorough understanding of the dynamics of these heating elements is essential for an effective design and operation of such devices. In this paper, we present a tractable feedback model that captures the dynamics of these microheaters. The operator model separates the thermal and the electrical response of the microheater into two operators, with a linear dynamic operator mapping the applied electrical power to the heater temperature and a second nonlinear but memoryless operator mapping the heater temperature to the electrical resistance. We present experimental results that show the identification of a write heater used in probe-based thermomechanical data storage and the accurate synthesis of arbitrary temperature profiles. In the application of microheaters as electrothermal probes, the signals being measured are believed to perturb the thermal system. Therefore, an extension of our model is presented to analyze the response to this perturbation. The extended model is used to identify and forecast the performance of electrothermal sensors, such as the read heater in probe-based data storage. Also presented are results on thermal position sensors, in which microheaters are employed as nanoscale position sensors for a MEMS-based microscanner.

Ultrashort Photonic Crystal Optical Switch Actuated by a Microheater

Abstract: We demonstrate a silicon photonic crystal (PhC) optical switch with a 20-mus response time controlled by a thermo-optic microheater. The switch consists of a dispersion engineered PhC directional coupler that is only 4.9 mum long. Optical and electrical isolation is provided by backfilling the holes and embedding the PhC in a silica cladding to produce a vertically symmetric structure that is more robust than a membrane geometry. No increase in optical loss is observed due to the silica cladding, despite operating above the lightline; the insertion loss for airbridge and silica embedded structures are comparable at 1-2 dB.

Design and integration of an all-in-one biomicrofluidic chip.

Abstract: We demonstrate a highly integrated microfluidic chip with the function of DNA amplification. The integrated chip combines giant electrorheological-fluid actuated micromixer and micropump with a microheater array, all formed using soft lithography. Internal functional components are based on polydimethylsiloxane (PDMS) and silver/carbon black-PDMS composites. The system has the advantages of small size with a high degree of integration, high polymerase chain reaction efficiency, digital control and simple fabrication at low cost. This integration approach shows promise for a broad range of applications in chemical synthesis and biological sensing/analysis, as different components can be combined to target desired functionalities, with flexible designs of different microchips easily realizable through soft lithography.

Silicon MEMS vaporizing liquid microthruster with internal microheater

Abstract: This paper reports a silicon MEMS vaporizing liquid microthruster (VLM) with an internal p-diffused microheater. The device fabrication and testing have been briefly described. The VLM consisting of two micromachined, bonded silicon chips produces thrusts in the range of 5 µN to 120 µN with a heater power of 1 W to 2.4 W at a water flow rate of 1.6 µl s−1 using an exit nozzle of throat size 30 µm × 30 µm. A maximum thrust of 120 µN was produced with a heater power of 2 W at a water flow rate of 0.7 µl s−1 with exit nozzle of throat size 50 µm × 50 µm. The measurement has been carried out using a sensitive cantilever and a laser based lamp-and-scale arrangement. The internal microheater is expected to yield a higher efficiency compared with the external microheater.