Research & Production Company MicroSensor Ltd

Our products [index.html] About Us Current International R & D Projects INTAS Project 2000-476 Temperature and Magnetic Field Sensors Meetings Contact Germanium Film Resistance Temperature Sensors Germanium film resistance temperature sensors can be used for static and dynamic temperature measurements in the 30 mK to 450 K temperature range. wide temperature range for operation (0.03 to 450 K) monotonic response over a wide temperature range small temperature reading errors for operation in magnetic fields small size extremely fast response to temperature changes high radiation tolerance high quality and low price The thermometers are based on Ge film resistors deposited onto semi-insulating GaAs substrates using vacuum technology. The sensitive thermometric chips are fabricated using microelectronic and micromachining technologies and mounted in various packages. At present two types of sensor packages are offered:- cylindrical canister packages, made from gold plated copper (3 mm in diameter and 5.0 mm long), and micropackages (1.2 mm in diameter and 1.0 mm long). The microthermometers (1.2 mm in diameter and 1.0 mm long) can be used when temperature measurement with high spatial resolution and small response time is required. They may also be incorporated in other packages, if high spatial resolution or small response times are not required. Characteristics of Ge-film thermometers Typical curves of temperature dependence of resistance and sensitivity for different models of thermometers Effect of magnetic field on thermometers Depending on the magnetic field value and temperature, the magnetoresistance for different types of thermometers can be positive or negative. The presence of magneto-resistance effect results in an error of temperature determination. Such an error can be presented as the ratio D T/T (%), where D T = T(B) - T, T is a temperature measured at B = 0, and T(B) is some temperature measured in the magnetic field B. Typical Temperature Measurement Errors, D T / T (in percent), as Function of Magnetic Field and Temperature Model Temperature (K) Magnetic induction (Tesla) 2.5 4 6 8 14 TTR-G 0.5 0.43 - 1.74 - 3.65 - 6.2 1.0 0 - 0.3 - 0.8 - 15.0 2.1 - 0.82 - 2.8 - 6.8 - 11.1 - 24.1 4.2 - 0.4 - 1.0 - 2.7 - 4.7 - 12.5 77.4 - 0.13 - 0.21 - 0.3 - 0.45 - 2.0 TTR-D 0.1 63.9 66.7 69.5 0.3 0.5 - 0.55 - 1.0 4.2 - 5.0 - 8.1 - 12.0 Design of Thermometers Micropackage (MP model) (1) and (5) copper discs; (2) gold strip; (3) corundum cylinder; (4) sensitive element; (6) copper wire; (7) tin. Canister package (CP model) (1) sensitive element; (2) copper can coated with gold film; (3) plate; (4) copper or phosphor bronze wires. Dimensions are given in millimeters. Back