저에너지 이온빔을 이용한 폴리이미드의 친수성 표면 개질 및 구리와의 접착력 증진 = Hydrophilic surface modification of polyimide and improvement of Cu adhesion by low energy and high density ion beam irradiation

다국어 초록 (Multilingual Abstract)

The changes of both wetting angle and surface energy of polyimide surfaces irradiated by Hall effect plasma thrusters with very low energy and high current density were investigated. Ar, O2, N2, and N2O were used for source gases and ion beam energy, current density and ion fluence were in the range of 180 eV - 200 eV, a few 100's μA/cm2, and 5x1015/cm2 - 1x1018/cm2 respectively. Ar+ ion irradiation reduced the wetting angle from 80o to 35o, but N2, O2, and N2O reactive gas ion beam irradiation successively decreased it down to 14o, 6o, and 2o at the ion fluence 5x1017/cm2. Surface energy of bare polyimide, 42.1 erg/cm, measured by dual anglometer using DI water and ethyleneglycol, was increased up to 65.2 erg/cm by Ar+ ion irradiation, and 81.2 erg/cm by O2+ and N2O+ ion beam irradiation. When mixed ion beam of Ar+ + O2+ was irradiated, the wetting angle was suddenly reduced below as low as 2o, and this was regarded as an very effective, productive and short processing condition for PI surface modification. Through X-ray photoelectron spectroscopy, surface energy was proved to be intimately related to the contents of carbonyl oxygen (C=O) induced on polyimide surface. From the measurement of peel strength between Cu film(10㎛) and PI, it was largely increased from 0.2-0.5 kgf/cm for Ar+ ion irradiated PI surface to 0.7-0.8 kgf/cm for reactive ion irradiated PI surfaces with C=O content higher than 10%.

목차 (Table of Contents)

• 제 1 장 서론............................................................... 1
• 제 2 장 이론적 배경 .................................................... 3
• 2-1. 폴리이미드의 표면처리 공정.................................. 3
• 2-1-1. 이온 보조 반응기구.......................................... 3
• 2-1-2. 저에너지 이온빔.............................................. 3
• 2-2. Ni-Cr / Cu 박막의 형성........................................ 4
• 2-2-1. 2-layer flexible copper clad laminate(FCCL)...... 4
• 2-2-2. DC magnetron sputtering methode.................... 6
• 2-2-3. Tie layer (Ni-Cr)............................................. 7
• 2-2-4. 구리/폴리머 계면의 화학반응............................. 8
• 2-2-5. 전기동도금 (Elector-plating)............................. 11
• 제 3 장 실험 방법........................................................ 13
• 3-1. 폴리이미드의 저에너지 이온빔 처리공정.................. 13
• 3-2. 구리박막의 증착 및 전기도금................................. 16
• 3-3 Cu / 폴리이미드의 신뢰도 실험.............................. 16
• 3-4. 표면 처리된 PI의 특성 분석................................... 19
• 3-4-1. 접촉각 측정.................................................... 19
• 3-4-2. XPS.............................................................. 20
• 제 4 장 결과 및 고찰.................................................... 22
• 4-1. 표면 처리된 폴리이미드의 표면 변화 분석................ 22
• 4-1-1. 폴리이미드의 접촉각 및 표면 에너지 변화............ 22
• 4-1-2. XPS 분석....................................................... 34
• 4-1-3. 접착력 측정.................................................... 42
• 4-1-4. SEM image.................................................... 45
• 제 5 장 결 론.............................................................. 47
• 참고 문헌................................................................... 49