학회 | 한국재료학회 |
학술대회 | 2010년 봄 (05/13 ~ 05/14, 삼척 팰리스 호텔) |
권호 | 16권 1호 |
발표분야 | B. Nanomaterials Technology (나노소재기술) |
제목 | The study of improvement in etching factor by controlling residual stress of Cu thin foil |
초록 | As the electronics using GHz frequency and portable system have been increased, interconnection technology of printed circuit board and electronic package has also been required to show their valuable performances. Especially, formation of finer pattern on printed circuit board affects multi-functions of final electronics such as device array, signal transmissibility and so on. Copper alloy has been used as interconnection materials for various electronics as mobile, display and IT devices. We have aimed at the optimized fabrications conditions of improving etching factor of copper pattern during subtractive process, where the copper pattern was etched by width of 100㎛ and pitch of 35㎛. The pattern under 35㎛ has been known as possible only with the semi-additive process, which is cost-consumable process with high failure cost. We investigated the relationships between residual stress and etching factor of copper pattern by subtractive process the analyzing grain sizes, grain distributions and stresses in copper foil during thermal conditions for relaxing residual stress. Generally, the electrolytic copper foil showed a residual stress about -55~60MPa as received, which easily caused to form copper patterns irregularly when the pattern was etched finely. We verified the compressive residual stress was relaxed with applying thermal conditions under 200℃ for a few hours. And also, we observed that the compressed residual stress of copper foil tended to be relaxed, constant, and compressed again during thermal condition, which is mainly considered as that the grain of copper is grown restrictively within a Cu thin foil layer. The relationships between residual stress and etching factor of copper pattern were analyzed in this works. We suggested a quantitative method for controlling grain size, grain distribution and relaxing stress of copper foil, which was very helpful for increasing an etching factor to decrease pattern width. |
저자 | 이효수, 이해중, 권혁천 |
소속 | 한국생산기술(연) |
키워드 | Cu thin foil; Thermal condition; Residual stress; Etching factor |