An electrode formed using a transparent conductive oxide is likely to be crystallized by heat treatment performed in the manufacturing process of a semiconductor device. In the case of a thin film element using an electrode having a significantly uneven surface due to crystallization, a short circuit is likely to occur and thus reliability of the element is degraded. An object is to provide a light-transmitting conductive oxynitride which is not crystallized even if subjected to heat treatment and a manufacturing method thereof. It is found that an oxynitride containing indium, gallium, and zinc, to which hydrogen atoms are added as impurities, is a light-transmitting conductive film which is not crystallized even if heated at 350° C. and the object is achieved.