Effect of lamination parameters on deformation energy of LTCC substrate based on Finite element analysis

In this paper, the temperature, time and pressure of the three process parameters were selected as three control factors of the low temperature co fired ceramic (LTCC) substrate laminating process. By using an L9 (33) orthogonal array which have 9 different process parameters' levels combinations were designed. The finite element analysis model of the LTCC substrate were established by using the finite element software ANSYS. The LTCC substrate was analyses by the method that thermal structural coupled finite element analysis under the different process parameters. The substrate deformation energy was calculated. Based on the deformation energy of different process parameters combination, the range analysis was performed. The results show that temperature is the dominant factor in effecting on deformation energy, holding time secondly and pressure at last; temperature 70°C , time 10min and pressure 25Mpa can reduce the substrate deformation and obtain excellent interlayer bonding effect. Combined with the references experimental results, the authors validate the conclusions are correct. Introduction Low temperature co-firing ceramic (LTCC) technology is an advanced passive integration and hybrid circuit packaging technology, it cannot only Package the resistor, capacitor and inductor, but also packaged by the IC integrated circuit module to be a complete circuit system. Because of the advantages of high frequency and high speed data communication, passive component and active component integration, high reliability, LTCC technology become the focus [1]. Low temperature co-fired ceramic (LTCC) substrate manufacturing process's lamination parameters includes temperature, pressure and time, however due to the combined effect of temperature, time and pressure, the laminated green tapes will produce deformation and delamination. The deformation and delamination will cause vertical interconnection dislocation and influence the electrical properties. Because of the uneven force and great material liquidity, the three-dimensional structures (such as surface channel, chamber, etc.) which embedded in multi-layer green tape often collapse [2].Analysis of lamination process characteristics, the green tape pressing quality is affected by temperature, pressure and time. To estimate the forming quality intuitively, this paper put forward with the deformation energy to estimate the index of forming quality. Then the lamination process was simulated based on orthogonal experiment. Finally, the authors analyzed and summed up the law of lamination process parameters effect on the green tapes so that achieve the purpose of guiding production. Warm Water Isotactic Pressing Technology Introduction This study research the lamination process which base on the warm water isostatic pressing technology. Warm water isostatic pressing technology mainly include stack, packaging, preheating, boosting, Holding pressure, decompression[3].Firstly, put the laminated green tapes into the vacuum bags. Then the packaged green ceramic tapes are vacuum. Finally, put the bag piece into the lamination cavity to laminate. The laminated green tapes structure is shown as Fig.1. Green tapes combined effects of temperature and pressure in water environment will soften and closely integrate International Conference on Intelligent Systems Research and Mechatronics Engineering (ISRME 2015) © 2015. The authors Published by Atlantis Press 1569 other green tape. After holding pressure and pressure relief process, the green tapes is removed from the laminated cavity to complete the lamination process. Fig.1 The laminated green tapes structure Finite Element Modeling In this paper, the substrate with 3D micro-channel structure embedded is composed of 26 layers of ferro-A6 green tape, and the dimensions of the green tapes is 40mm by 50mm by 0.127mm. The dimensions of the main runner is 36mm by 2.2mm, and the dimensions of branch runner is 30.2mm by 1mm. The sacrificial material is embedded into the micro-channel. The dimensions of sacrificial material is 30.1mm by 0.9mm. Combined with requirements of RF function module dimensions and neglect of the effect of conductor on the deformation energy, corresponding three-dimensional geometric model is established. The overall geometry model as shown in Fig.2, the micro-channel sacrificial material model as shown in Fig.3, relevant dimensions are summarized in table 1. Fig.2. overall geometry model Fig.3. Micro-channel sacrificial material model Table 1.The geometric size of the model dimension green tape main runner branch runner sacrificial material Length (mm) 50 36 30.2 30.1 Wide( mm) 40 2.2 1 0.9 Thickness (mm) 3.302 0.508 0.508 0.508 Fig.4 Finite element model of green tapes Fig.5 Finite element model of sacrificial material