AR, FCR, RCA, RCN thin film resistor series are formed by vacuum depositing a resistive alloy on a usually flat substrate of ceramic. Photo-lithographic or similar techniques are used to define the final geometry and interconnecting traces. Thin film technology provides for close ratio matching and tracking in a network, as well as low stand-alone temperature coefficient and resistance tolerance. Types includes ultra precision (AR), precision (FCR), array (RCA), and networks (RCN).