高温共烧陶瓷封装外壳生瓷加工精度的控制

Accuracy Control of Green Ceramic Machining in High Temperature Co-Fired Ceramic Package

高温共烧陶瓷(HTCC)封装外壳内部布线的位置精度直接影响着内部线路的稳定性。简述了陶瓷封装外壳加工工艺流程和在生瓷加工阶段影响位置精度的主要因素,包括生瓷料片加工形变特性及冲孔工艺、印刷工艺及叠片工艺的加工精度等。重点分析了生瓷片预处理、冲孔设备选择及工作台移动参数、印刷高度及叠片工艺对陶瓷封装外壳内部布线位置精度的影响。通过实验研究得到改善陶瓷封装外壳内部布线位置精度的关键数据。生瓷带料预处理工艺采用等静压机预压方式,以100psi(1psi≈6895Pa)的压力对生瓷料片进行2~3min预压,提高带料密度,减小生瓷加工过程中的变形;冲孔工艺选用激光冲孔方式,通过调整激光冲孔设备加工参数(工作台移动速度200mm/s),提高冲孔设备工作台移动位置精度,进而提升冲孔位置精度;印刷工艺采用丝网印刷方式和电荷耦合器件(CCD)自动对位方式,并通过规范印刷高度(2mm左右),提升印刷位置精度;叠片工艺中通过先叠片再去膜的方式提升叠片精度。最终实现层间布线位置精度≤20μm的陶瓷封装外壳的生产。

The position accuracy of internal wiring directly affects the stability of the internal wiring in high temperature co-fired ceramic(HTCC)packages.The production technical process of ceramic package and the main factors affecting the positional accuracy in the stage of green ceramic machining were decribed,including the deformation characteristics of green tapes during machining,as well as the machining accuracies of punching,printing and lamination processes,et al.The influences of the pretreatment of green tapes,the selection of punching machine,the movement parameters of worktable,the printing height and the lamination process on position accuracy of internal wiring in ceramic package were mainly analyzed.The key data to improve the position accuracy of internal wiring in ceramic package were obtained by experimental research.The pretreatment process of green tapes adopts the prepressing method with isostatic pressing machine.The green tapes are prepressed at the pressure of 100 psi(1 psi≈6895 Pa)for 2~3 min to improve the densities of tapes and reduce the deformation of green tapes during machining.Laser punching is selected for the punching process,the moving position accuracy of punching equipment worktable improves by adjusting the processing parameters(the moving speed of worktable of 200 mm/s),and the accuracy of the punching position is further improved.The printing process adopts the screen printing method and charge coupled device(CCD)automatic alignment method,and printing positional accuracy is improved by standardizing the printing height of about 2 mm.The lamination accuracy is improved by the way of first lamination and then removing film in the lamination process.Finally,the production of ceramic package shell with the interlayer wiring positional accuracy of not more than 20μm is achieved.