Original Paper(Vol.62 No.2 pp.149-155)

Tensile Properties and Viscoelastic Model of a Polyimide Thin Film

Shengde ZHANG, Syuhei MORI, Tadashi NAGASAWA, Kaoru KOBAYASHI and Masao SAKANE

Abstract:This paper presents tensile properties of a new developed polyimide thin film used in electronic devices. Tensile tests were performed to determine Youngfs modulus, proportional limit, yield stress, ultimate tensile strength and elongation of the polyimide film at three strain rates and three temperatures. Effects of strain rate and temperature on the tensile properties were discussed. There was a little anisotropy of tensile properties caused by injection direction in the polyimide film. Young's modulus, proportional limit, yield stress and ultimate tensile strength increased with increasing the strain rate. Only elongation decreased with the strain rate. Youngfs modulus, proportional limit, yield stress and ultimate tensile strength decreased with increasing temperature but elongation increased. Applicability of a viscoelastic model for describing the stress-strain curves of the polyimide film was proposed.

Key Words:Polyimide, Thin film, Tensile properties, Viscoelastic model, Electronic device