Method and apparatus for heating and controlling the temperature of ultra small volumes

Abstract

Abstract The present invention relates to an apparatus for the controlled heating of an ultra small volume. The invention provides a means of heating, measuring, and controlling the temperature in such ultra small volume. The present apparatus includes a heat-sensor portion comprised of an electrical resistance. Heat is generated in the heat-sensor portion by a flow of electrical current through such electrical resistance. The temperature in the heat-sensor portion is determined by measuring the electrical resistance of the circuit that includes the heat-sensor element. The apparatus is comprised of a thin-walled microcapillary tube filled internally with an electrically conductive material and coated externally with a dissimilar electrically conductive material. The external electrically conductive coating on the microcapillary tube is suitable a noble metal such as gold. The external metal coating preferably has a metallic overcoat to improve conductivity, and more preferably has a further overcoat, or outside layer, of a nonconductive material. Along the tip portion of the microcapillary tube the two dissimilar conductive materials (internal and external) meet to form a juncture of electrical resistance. This juncture is the heat-sensor portion serving both as the heating element and as the temperature sensor. The electrically conductive material inside the microcapillary tube and the electrically conductive coating on the outside of the microcapillary tube are connected to an electrical source as part of an electrical circuit.

Inventors

• 👤 Frederick Sachs
• 👤 Anthony Auerbach
• 👤 Richard G. McGarrigle
• 👤 James E. Neil

Bibliographic Details