THICK-FILM RESISTOR TRIMMING METHOD AND DEVICE Russian patent published in 2002 - IPC

FIELD: microelectronics and electronic engineering; thick-film resistor manufacture. SUBSTANCE: trimming method based on exposure of resistive film to electrical spark discharge involves changing distance between discharge electrode and surface of resistor upon trimming the latter. So, when trimming to raise resistor ratings including destruction of resistive layer, electrode-to-resistor distance is set between 0.25 and 0.5 mm; when trimming to reduce resistor ratings without destruction of resistive layer, it is set between 2 and 2.5 mm. Trimming device implementing this method has series-connected standard resistance box, comparison unit, trimming direction control and selection unit, contact probes, discharge electrode, and discharge-electrode power unit incorporating low-frequency generator connected to first 2AND gate, high-frequency generator connected to second 2AND gate, high-voltage converter whose inputs are connected to outputs of 2AND gates and outputs, to contact probe coupled with common bus and to discharge electrode; newly introduced in device are discharge-electrode displacement operating mechanism control unit whose inputs are connected to outputs of trimming direction control and selection unit and discharge electrode displacement operating mechanism whose input is connected to output of operating mechanism control unit. EFFECT: enhanced trimming speed and twice as high post-trimming stability of resistor values. 2 cl, 3 dwg, 1 tbl