A high resolution resist material comprising an acid generator is provided so that high sensitivity and high resolution for high energy rays of 300 nm or less, small line-edge roughness, and excellence in heat stability and storage stability are obtained. Moreover, a pattern formation method using this resist material are provided. Specifically, a novel compound of the following general formula (1); and a positive resist material comprising this compound preferably as a photo acid generator, and a base resin; are provided. This positive resist material may contain a basic compound or a dissolution inhibitor. Further, the present invention provides a pattern formation method comprising the steps of applying this positive resist material on a substrate, then heat-treating the material, exposing the treated material to a high energy ray having a wavelength of 300 nm or less via a photo mask, optionally heat-treating the exposed material, and developing the material using a developer. ##STR00001##