Impact of wafer surface profile on IC packaging

Abstract

In this paper, delamination occurred in Plastic Quad Flat Package (PQFP) had been found after mol-process. From the prelirmnary observation, the wafer surface profile is different from the others from atomic force microscopy (AFM) analysis, for example, the pitch and trench of local die surface. Herein a stress simulation was performed to characterize the interaction among the molding compound formula design, molding process and wafer surface topography. The results show that the wafer topography does have a significant impact on in-situ molding process. Aside from simulation, the Fourier Transform Infiared Spectrometry V I R ) was used to characterize the uniformity of top layer passivation. The result showed that the uniformity of deposited passivation was not quite homogeneous as compared to the well-stunk area, of that might cause insufficient adhesion in which contributed by low density of chemical bonding in the interface. Therefore, wafer surface topography and its chemistry do have a significant impact in IC pack-.

Neural Network based Classification of Material Type and its Surface Properties

“…Characterization of material and its surfaces for quality control is an important aspect of many manufacturing processes. Significant work has already been done in the classification and determination of surface roughness [1][2][3][4][5][6][7][8]. There are some methods to determine the surface properties by sensor technologies, such as image, infrared, tactile, etc.…”