Microheater

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

Evaporating source for organic material

Abstract: PROBLEM TO BE SOLVED: To provide an easily treatable evaporating source for an organic material capable of executing uniform heating at a certain temp. to various organic evaporating materials, particularly, to liq. organic evaporating materials. SOLUTION: A vessel 3 for evaporation housing an organic compound monomer 2 and a heating medium source 4 controlling the temp. of a heating medium 40 in a heating medium tank 45 to a prescribed one are provided. The vessel 3 for evaporation is composed of a housing part 30 housing the organic compound monomer 2 and a heating medium holding part 31 provided so as to surround the vicinity of the housing part 30, and a heating medium circulating path 32 is formed by the space between the housing part 30 and the heating medium holding part 31. The heating medium 40 is introduced into the heating medium circulating path 32 from the heating medium source 4 and is circulated, and the organic compound monomer 2 in the housing part 30 is heated and cooled. A microheater 62 for heating the organic compound monomer 2 to a temp. higher than that in the vessel 2 for evaporation is wound around the heating medium holding part 31.

Batch Nanofabrication of Suspended Single 1D Nanoheaters for Ultralow-Power Metal Oxide Semiconductor-Based Gas Sensors.

Abstract: The demand for power-efficient micro-and nanodevices is increasing rapidly. In this regard, electrothermal nanowire-based heaters are promising solutions for the ultralow-power devices required in IoT applications. Herein, a method is demonstrated for producing a 1D nanoheater by selectively coating a suspended pyrolyzed carbon nanowire backbone with a thin Au resistive heater layer and utilizing it in a portable gas sensor system. This sophisticated nanostructure is developed without complex nanofabrication and nanoscale alignment processes, owing to the suspended architecture and built-in shadow mask. The suspended carbon nanowires, which are batch-fabricated using carbon-microelectromechanical systems technology, maintain their structural and functional integrity in subsequent nanopatterning processes because of their excellent mechanical robustness. The developed nanoheater is used in gas sensors via user-designable localization of the metal oxide semiconductor nanomaterials onto the central region of the nanoheater at the desired temperature. This allows the sensing site to be uniformly heated, enabling reliable and sensitive gas detection. The 1D nanoheater embedded gas sensor can be heated immediately to 250 °C at a remarkably low power of 1.6 mW, surpassing the performance of state-of-the-art microheater-based gas sensors. The presented technology offers facile 1D nanoheater production and promising pathways for applications in various electrothermal devices.

Demonstration of Reduced Power Consumption MEMS LEL Sensor Prepared by a Novel Digital Microfluid Technique

Abstract: A low power consumption micro electro-mechanical system catalytic combustible low explosion limit (LEL) sensor was fabricated. The microheater was characterized by a suspending microhotplate over the silicon substrate. The alumina slurry and Pd-Pt catalyst solution were precisely and repeatedly coated on the microhotplate by a novel digital microfluid technique, respectively. Furthermore, the alumina layer and the alumina/catalyst layer on the microheater showed the collinear resistance versus voltage thermal characteristic curves during the solidification, which indicated that a good match could be directly made between them. During aging, the alumina/catalyst element demonstrated a high initial signal and then fell rapidly before coming to a stable value. Through pairing the alumina reference and alumina/catalyst sensitive elements in the wheatstone bridge, the output voltage could be up to 36 mV at the 50% LEL level of CH4 at the working temperature of 400 °C and the operation voltage was 2.6 V. The power consumption and the signal sensitivity could be also down to 75 mW and up to 0.702 mV/LEL%, respectively.

Method for forming silicon film, method for forming pn junction and pn junction formed using the same

Abstract: A method for forming a silicon film may be performed using a microheater including a substrate and a metal pattern spaced apart from the substrate. The silicon film may be formed on the metal pattern by applying a voltage to the metal pattern of the microheater to heat the metal pattern and by exposing the microheater to a source gas containing silicon. The silicon film may be made of polycrystalline silicon. A method for forming a pn junction may be performed using a microheater including a substrate, a conductive layer on the substrate, and a metal pattern spaced apart from the substrate. The pn junction may be formed between the metal pattern and the conductive layer by applying a voltage to the metal pattern of the microheater to heat the metal pattern. The pn junction may be made of polycrystalline silicon.

A simple approach for the precise measurement of surface temperature distributions on the microscale under dry and liquid conditions based on thin Rhodamine B films

Abstract: The precise measurement of surface temperatures on the microscale is of major importance for lab-on-a-chip applications that deal with temperature-dependent processes. For that, thermometric methods that combine high temperature resolution with feasibility, flexibility and applicability in aqueous environments are strongly required. Here, we present and characterize an easy approach for surface temperature measurements based on thin films of commercially available sol-gel that contain the temperature-sensitive fluorophore Rhodamine B. These films can be applied onto various surfaces in an easy two-step process and allow for temperature mapping on the microscale under both dry and liquid conditions. To demonstrate the potential of the approach we measured the temperature distribution at the surface of resistive microheaters. We analyzed minute surface temperature gradients and conducted time-dependent measurements. This demonstrated the high resolution regarding temperature (