| 摘要 |
PURPOSE:To protect a magneto-sensitive thin-film positively from damage, and to improve reliability by using a protective film in double layer structure consisting of the fixed quality of film. CONSTITUTION:An silicon oxide film (a sputtering SiO2 film) 4 in thickness of 0.1-0.8mum deposited and formed through sputtering treatment is shaped onto an insulating substrate 1 containing a magneto-sensitive thin-film 2, and an silicon nitride film (a plasma SiN film) 5 in thickness of 0.5-2.5mum deposited and formed through plasma treatment is shaped to the upper section of the oxide film 4. Protective films in at least double layer structure are formed by these sputtering SiO2 film 4 and plasma SiN film 5. The thin-film 2 cannot be step- covered sufficiently when the thickness of the SiO2 film 4 extends over 0.1mum or less, and the number of pin holes suddenly increases when the thickness of the SiO2 film 4 extends over 0.8mum or more. When the film thickness of the SiN film 5 extends over 0.5mum or less, pin holes in the SiO2 film 4 are not buried sufficiently. When the film thickness of the SiN film 5 extends over 2.5mum or more, cracks are generated in the surface of the SiN film 5. Accordingly, an improvement in reliability can be expected by using a protective film in predetermined film thickness. |
