In 1885, C. Bradley of England invented the molded carbon solid core resistor. In 1897, T. Gambrill and A. Harris in England made carbon film resistors with carbon-containing ink. In 1913~1919, W. Swan of the United Kingdom and F. Kruger of Germany successively invented metal film resistors. In 1925, the German company Siemens-Halsk invented the thermal decomposition carbon film resistor, breaking the monopoly of the carbon solid core resistor market. After the advent of transistors, the requirements for the miniaturization and resistance stability of resistors have become stricter, which has promoted the development of various new resistors. In 1959, Bell Labs developed a TaN resistor. Since the 60s, new processes such as drum magnetron sputtering and laser resistance fine-tuning have been adopted, and some products have developed in flat, integrated, miniaturized and flaked.
