Copper electroplating for fabricating thin film circuits was carried out under four rectifier output waveforms (including high-to-low waveform, direct current, single-phase full-wave rectification, and unidirectional pulse) in cyanide-free alkaline and acidic baths, respectively. The deposition rate, thickness-to-width ration of microstrip, as well as surface morphology, roughness, uniformity, and adhesion strength of copper coating under different experimental conditions were studied. The adhesion strength of the copper coatings obtained in both baths are qualified. As compared with each other, the alkaline citrate bath has higher deposition rate, while the acid bright sulfate bath produces copper coatings with higher brightness, better uniformity, and smaller roughness and microstrips with higher thickness-to-width ratio. Different waveforms have different effects on the properties of copper coating. Single-phase full-wave rectification and unidirectional pulse waveforms are suitable for fabricating highly precision microstrips.%在薄膜电路镀铜生产中分别选用4种整流器输出波形(包括高低自由波、直流、单相全波整流和单向脉冲)及无氰碱性镀铜液与酸性镀铜液各一种进行试验,考察了不同条件下的镀速,薄膜电路微带线的厚宽比,以及镀铜层的表面形貌、粗糙度、均匀性和附着力.两种镀液体系所得镀铜层的附着力均满足质量要求.两相比较,碱性柠檬酸盐镀铜体系具有较高的镀速,而酸性硫酸盐光亮镀铜体系所得铜层光亮度较高、厚度均匀性较好、粗糙度较小,制作的微带线的厚宽比也较大.整流器输出波形对镀铜层各方面性能有一定的影响.单相全波整流以及单向脉冲波形适用于高精度线条的制备.
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