关键词: 先进封装, 铜填充, 高深宽比通孔, 脉冲反向电镀, 玻璃通孔

Abstract: With the advancement of packaging towards three-dimensional integration, glass through via (TGV) metallization technology has become a critical component for vertical interconnections between chips. The defect-free copper filling of high aspect ratio glass through via presents inherent challenges in mass transfer and deposition kinetics. This process is highly susceptible to premature sealing due to excessive copper deposition at the vias opening, resulting in porosity at the through-vias center and thus constituting a key technological bottleneck. This paper investigates a novel synergistic approach combining pulsed reverse plating with additive regulation, utilizing domestically produced electroplating solutions. By leveraging self-levelling effect of pulsed reverse current and selective adsorption properties of additives, defect-free electroplating filling of high aspect ratio glass vias is achieved. For glass vias with varying shapes (X-shaped and vertical) and aspect ratios (AR 4, 10, 15), quantitative process window design and optimization are achieved through Thiele modulus theory analysis and investigations into pulse parameters and additive concentrations. Experimental results demonstrate: for X-shaped vias with an aspect ratio of 4, conformal deposition can be achieved through pulse control in the absence of additives, whilst rapid bridging within 30 minutes is possible with the addition of additives. For X-shaped vias with an aspect ratio of 10 and vertical vias with an aspect ratio of 15, raising inhibitor and levelling agent concentrations to 12 ml/L combined with a multi-stage current method effectively suppresses aperture closure, enabling void-free filling.

Key words: advanced packaging, copper filling;, high aspect ratio via, pulse reverse plating, through glass via