## 2 Background and Related Work  
**Traditional SAM system**: Conventional SAM systems employing linear motors for rapid scanning have been widely used in wafer material quality assessment studies. [PERSON] et al. demonstrated the application of high-frequency SAM for identifying subsurface damage, residual stress, and coating thickness in wafers and other materials [7]. [PERSON] et al. employed SAM for the comprehensive evaluation of silicon wafers, including thickness and chamfer measurements, surface and subsurface analysis, and the detection and characterization of internal defects [8]. Additionally, [PERSON] et al. utilized SAM and silicon wafer samples to assess resolution limits across different transducers, providing valuable insights into the capabilities of SAM for HR imaging [9]. However, these experimental studies primarily utilized SAM as an inspection tool for wafer evaluation without implementing any mechanical modifications to the system to reduce scanning time or enhance the overall performance of the SAM system. **R-SAM system**: Our new R-SAM system retains the core components of the traditional SAM system, including a scanning stage, ultrasound transducer, pulser/receiver, digitizer,and PC [10]. However, it introduces a significant enhancement by replacing the linear motor with a rotary motor to improve system performance (see details in Supplementary Movie S1). This design modification enables smoother and more consistent motion during the scanning process, particularly for large-area samples, addressing the limitations of linear motor-based systems in terms of scanning speed and mechanical precision. The current iteration of the R-SAM system represents a tailored solution specifically designed for the inspection of 12-inch wafer samples, demonstrating a significant advancement in NDT for semiconductor applications. The integration of a rotary motor enhances the scalability and throughput of the system, making it highly efficient and suitable for large-scale industrial wafer inspections. **Linear acoustic images in the R-SAM system**: Figure 1 shows a linear scanned image. To support the new rotational movement, we developed specialized software designed to integrate seamlessly with the R-SAM system, ensuring efficient data acquisition and processing. This software synchronizes the rotary motor with the data collection process, allowing for precise control of the scanning trajectory and maintaining consistent image resolution across the entire scanning area. The raw scan data is initially acquired in a linear format, which is subsequently transformed into a polar coordinate representation for further processing and visualization (as presented in Figure 1). In this study, we chose to apply the LinearTGAN model to the linear scan data rather than the polar coordinate representation, as the linear format retains the original, unprocessed data, ensuring data integrity and minimizing the risk of information loss during the transformation process. This approach ensures that the deep learning model operates on the most accurate and complete form of the input data, enhancing the reliability of the reconstructed HR images while preserving key structural details essential for accurate wafer inspections. **Acoustic image SR and measurement**: Traditional methodologies, such as the inversion model [11], synthetic aperture focusing technique (SAFT) [12], and nonlinear coupling methods [13], have significantly improved the resolution of SAM imaging, enabling more detailed and precise analyses. However, these techniques face several limitations. For instance, inversion models are computationally complex and sensitive to noise, affecting image quality with large datasets. SAFT, despite enhancing resolution through virtual  
Figure 1: **(a)** The original linear scanned image; **(b)** the processed image in polar coordinates. aperture synthesis, is resource-intensive and prone to artifacts with non-uniform samples.