By using an atomic force microscope (AFM), we discuss validity of analysis method of adhesion and cohesion property of micro photoresist pattern. Dot shaped photoresist patterns, 0.60μm in square and 1.01μm in height were formed onto a flat substrate by photolithography. Load for collapse of photoresist pattern and its deflection are measured by applying load with an AFM micro tip. By combining with stress and deformation analysis by finite element method, internal stress for collapse and Young's modulus of the photoresist pattern can be obtained. These value increase with heating temperature of photoresist pattern. By the thermal analysis of weight loss, hardness and refractiveindex, we confirmed the validity of this method. This method can be applied to adhesion and cohesion analysis of micro condensed matter adhered on a flat substrate.

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The crack growth behavior on the cleavage adhesive joints with various adhesive thicknesses was investigated by the echo characteristic of surface wave emitted toward the adhesive layer under the tensile load. The cross section of adhesive layer was 25×25mm². The echo height reflected from the edge of the adhesive layer and the round-trip propagation time from the surface wave probe to the adhesive layer were measured for evaluating the crack growth behavior. The crack was generated along the adhesive interface when the ratio of the round-trip propagation time suddenly increased. After that, the crack rapidly grew. In the case where the distance between the surface wave probe and the adhesive layer was10mm, the crack of the adhesive layer was detected when the crack length was more than 0.2mm or the ratio of the echo height reflected from the edge of adhesive layer became about 60%. Moreover, the crack growth behavior was evaluated for measuring the ratio of the round-trip propagation time or the ratio of the echo height. The load of crack generation detected by the change ratio of the round-trip propagation time agreed well with that of the echo height. The load of crack generation and breaking load on the adhesive layer decreased as the adhesive layer thickness was thicker.

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This study investigates the interdiffusion of a poly (isobutylene) into a poly (butylacrylate) layer. The presence of interdiffusion at the adhesive/polymer substrate interfaces is essential for the development of pressure sensitive adhesive tapes. Attenuated Total Reflectance Fourier Transform Infrared Spectroscopy (FTIR-ATR) studies have been used to characterize the interdiffusion behavior. The interdiffusion and reptation behavior was studied at various time intervals by measuring the changes in absorbance bands of selected characteristic peaks in each polymer. The interdiffusion time of poly (isobutylene)/ poly (butylacrylate) depended on the molecular weight of poly (isobutylene) (t～M^1.2～1.5) . Still more,different behavior of interdiffusion between above and below the critical molecular weight (Mc) was observed.

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