Cr/Au meander-shaped resistors were fabricated on 0.2 μm thick square-shaped silicon nitride diaphragms with diaphragm dimensions ranging from 0.775 to 2.275 mm. The performance of these sensors was measured in a vacuum chamber as a function of resistor powers from 0.5 to 3 mW at pressures ranging from 2×10−4 to 760 Torr. The lengths of the meander-shaped resistors increase from 5.5 mm for the 0.775 mm diaphragm to 33.6 mm for the 2.275 mm diaphragm devices. It is shown that the pressure dependence of the devices is governed by the kinetic gas theory and that the devices can measure pressures from about 10 to 1×10−3 Torr. At a resistor power of 2 mW at 760 Torr, the 2.275 mm diaphragm device, which has the largest sensing area, exhibits the highest sensitivity.

High-quality, micrometer scale, corner cube arrays were grown on (111) silicon substrates by selective epitaxial growth (SEG) techniques. Sixteen different arrays were produced that had periodic corner spacing ranging from 3 to 50 µm. The arrays were formed by suppressing silicon SEG in a regular geometric pattern, producing the three mutually perpendicular (100) smooth crystal planes. For coherent light of 633-nm wavelengtha sharp diffraction pattern of threefold symmetry was observed out to 7 maxima, as well as a retroreflection component.

Cr/Au meander-shaped resistors were fabricated on 200nm thick square silicon nitride diaphragms on silicon with diaphragm dimensions of 0.775mm, 1.025mm, 1.275mm, 1.775mm, and 2.275mm. At 760Torr, the resistors were heated to about 20°C -60°C above ambient by Joules heating and the resistances were monitored as a function of pressure from 760Torr to 2x10 -4 Torr.As expected from kinetic theory, the sensitivity of the gauges shifted from high to low pressure with increasing diaphragm size (distance from the heat source to the cold junction). Measurements were taken at powers ranging from 0.6mW to 6mW. The sensors were applied to measure potential vacuum bursts due to outgassing events in field emitters and to measure the pressure inside of glass capillaries.