I. A. Korzh

The paper describes the technology for forming thin-film resistors with low and high values of surface resistance using one resistive material - tantalum. High-resistivity Ta films with a specific surface resistance of 50 Ohm/square, separating intermediate yttrium film with a specific surface resistance of 200-300 Ohm/square, low-resistivity Ta films with a specific surface resistance of 3-5 Ohm/square and Cu-based conducting films are deposited by magnetron sputtering within a single vacuum cycle. The length and width of both high-value and low-value resistors and resistor pads are simultaneously formed by photolithography after which the low resistance film is etched up to the yttrium intermediate film and then the yttrium film is removed from the surface of the high resistance film using the etchant not etching high resistance TA film. Ta films are removed by hydrofluoric acid-based etchants. The hydrofluoric acid has no affect on the yttrium films. Yttrium films are etched by the nitric acid which has no effect on the tantalum film. Thus we form simultaneously from one material low-value and high-value resistors with a wide range of the resistance change (at least 10 times for equal resistor length and width) and equal TCR. Examples of using this technology are given. Low-value resistors 1-10 Ohms and high-value resistors 100-1000 Ohms with an accuracy of better than 1 % and with the same TRC values (less than 200 ppm) for T-branches of HF power attenuators are obtained.