| 摘要 |
PROBLEM TO BE SOLVED: To alleviate the stress in the tangent direction and simultaneously control generation of a stress in the thickness direction, by controlling anisotropic axis that provides the maximum anisotropic characteristic in the predetermined direction using a material showing anisotropic property of thermal stress for a resin layer provided for a passivation film. SOLUTION: After a passivation film 3 having the predetermined aperture 8 on a semiconductor element 1 is formed, this film is coated with a photosensitive polyimide varnish that becomes a first resin layer 4. Next, after a conductor wire 6 is formed, the water content absorbed by the first resin layer 4 is eliminated through a thermal treatment for two hours at 140 deg.C and a porous polyimide film (second resin layer 5, hole diameter is 0.5μm or less) that is previously processed to the predetermined shape is pressed in close contact under the pressure of about 10 N/m at 230 deg.C. Since this porous polyimide film has the through hole in the thickness direction (vacant hole rate is about 30%), anisotropic property is obtained for the stress in both tangent direction and thickness direction (elastic property rate in the thickness direction = 2.5 Gpa, line expansion coefficient in the thickness direction = about 40 ppm/ deg.C, elasticity coefficient in the tangent direction is 1.8 Gpa, line expansion coefficient in the tangent direction is about 100 ppm/ deg.C).
|
