高开孔率、大厚度金属精细网板的制造是网板业界的技术难题。分析了现有的精细金属网板制造工艺的优缺点,并提出采用基于SU-8光刻胶的UV—LIGA技术来制备高开孔率大厚度精细金属网板的工艺思路。优选了关键工艺环节的操作参数,表征了试样的形貌特点,检测并分析了试样的相关性能。结果显示,采用优化的工艺条件(前烘65℃/20min,95℃/20min;适量曝光剂量;后烘65℃/10min,95℃/15min;匀胶后静置、随炉冷却;超声辅助显影等)所制备的六边形镍网(边200μm),不仅开孔率高(88%),厚度大((120±3)μm),且具有尺寸精度高(形位误差±2μm)、孔形一致性好(筋宽偏差〈3μm)、孔壁平滑等特点。结果表明,UV—LIGA技术是一种制备高通孔率、大厚度精细金属网的有效工艺手段。
The manufacture of thick micro-precision sieve-sheets with high open areas is a key technical challenge. After analysis on the process limitations existing in three manufacturing methods for metal micro-precision sieves, an optimized UV LIGA technique based on SU-8 photoresist is presented to manufacture the micromesh nickel sieve sheets. Operational parameters of some key process steps for fabricating micro-precision sieve-sheets are determined experimentally, and morphological characteristics of electroformed hexagon micromesh nickel sieves are evaluated using a SEM and an optical profi ler. Experimental results show that, using the UV LIGA process, hexagon mieromesh nickel sieves (200 μm in side length,50 mm in diameter and 120μm in thickness) with an open area percent of 88% and a sheet thickness of 120 μm, which can hardly be achieved by the conventional machining methods, are successfully machined. The machined sieves are characterized by their smooth surfaces and aperture walls, high precision sizes as well as rigid and homogeneous structures. These results show that the UV-LIGA is an excellent method for fabricating micro-precision metal sieves.