Cobalt tungsten phosphorus electroless deposition process and materials

摘要

Materials and methods are described for electroless deposition of cobalt phosphorus and cobalt tungsten phosphorus, employing tungsten trioxide or tungsten phosphoric acid as a source of tungsten. Electolessly deposited metals produced are substantially devoid of alkali metal ions and alkaline earth metal ions. The deposits are typically oxygen-free thin films having a low sheet resistivity of less than 50 muOmega.cm. The films may be used as capping layers or barriers for the prevention of interlayer metallic drift, diffusion and migration in semiconductor, ULSI, VLSI, electroplating industries and products.