Gold Wire Bonding Quality Inspection of Integrated Circuit Based on Slenderness-Rotated Object Detection

Gold wire bonding is a critical interconnection technique for integrated circuit, connecting chips to substrates and enabling communication through slender wires. Gold wires are characterized by slenderness, small size, and multiangle distribution. Meanwhile, manufacturing errors during gold wire bonding further complicate quality inspection. In this article, we propose a fully automated gold wire bonding quality inspection framework to detect missing and misconnection wires. Given the small diameter of the gold wire (typically around 0.025 mm) and the complexity of the background, capturing high-quality images is crucial for effective quality detection. Therefore, we first design a gold wire image capture system that integrates a high-resolution camera and lens with a high-precision three-axis motion platform. This system can automatically acquire image data for both the product to be inspected and the defect-free template. Subsequently, we introduce a slenderness attention module (SAM) to detect slender wires with arbitrary orientations. We employ an attention mechanism that combines channel and spatial attentions, facilitating precise identification from complex background images. We, then, establish a wire quality evaluation (WQE) model for gold wire bonding quality inspection, which integrates geometrical information and data from the manufacturing process. The experimental results on our gold wire dataset demonstrate the effectiveness of the proposed method in gold wire bonding quality inspection, achieving an average precision (AP) of 85.8%, with precision (P) and recall (R) rates of 88.1% and 88.8%, respectively. The WQE model accurately identifies missing and misconnection wires. It outperforms intersection over union (IoU)-based and similarity-based (SiM-based) methods by detecting all defects in 16 representative images, including dense and sparse wire arrangements.