When selecting a PCB for sensor applications, you must prioritize signal integrity and thermal management. Key specifications include the base material (FR-4, High-TG, or Ceramic) depending on the operating temperature, and copper thickness (typically 1oz to 2oz) to ensure stable power delivery. For high-precision sensors, ensure the supplier supports fine line/space tolerances (down to 3/3 mil) and offers controlled impedance to prevent signal distortion. Additionally, the surface finish (such as ENIG - Electroless Nickel Immersion Gold) is critical for ensuring excellent solderability and oxidation resistance for sensitive sensor components.