This is a research program to develop a very high resistance value resistor chip for use in hybrid circuits. The chip size will be approximately .050 x .050 inches, will employ a resistive material on a polished substrate such as silicon, glass, or quartz and will have two or more pads for wirebond attachment. The film bulk resistivity will be 104-107 micro-ohm cm which, for a 1000 Angstrom film, corresponds to a value range of 108-1011 ohms. Desirable electrical characteristics include low voltage coefficient of resistance, low noise, and low capacitance to ground.Resistors of this value range are difficult to produce due to the lack of suitable thin film materials. Thick film materials are available; however, they exhibit problems with high noise, large values of voltage coefficients of resistance, and instability over life.The program consists of three parts; . literature search for candidates for very high resistivity film; . investigation of improvements in measurement techniques for high resistance/low current applications; . sputter experiments and photolithographic fabrication of samples of thin film candidates.National Institute of Neurological Disorders and Stroke (NINDS)
