INSULATING FILM, ELECTRONIC DEVICE HAVING INSULATING FILM AND FORMATION OF INSULATING FILM

摘要

PURPOSE: To provide an insulating film having sufficient thickness against pinhole and excellent in the insulating film property of substrate. CONSTITUTION: A glass protective film to be formed on an insulating substrate 21 is formed into two layers of an under layer protective insulating film 29a composed of tantalum oxide and an upper layer protective insulating film 29b composed of tantalum oxide having higher oxygen content than that in the under layer protective insulating film 29a. In this way, the upper layer protective insulating film 29b is not deteriorated in insulating property due to impressed electric field and exhibits excellent electric insulating property. And, since the under layer protective insulating film 29a is formed with lower oxygen content than that of the upper layer protective insulating film 29b, the insulating film is formed with high sticking rate and is formed so as to have sufficient thickness against pinhole to protect the insulating substrate 21.