What technique is typically used for creating printed circuit boards?

The technique commonly used for creating printed circuit boards (PCBs) is etching. This process involves removing layers of copper from the surface of a PCB to create the desired circuit patterns. Initially, a layer of photoresist is applied to the copper-clad board, and then the board is exposed to ultraviolet light through a mask that outlines the circuit design. The exposed areas of the photoresist are then developed and washed away, revealing the copper underneath.

Subsequently, the board is subjected to an etching solution (typically acid-based) that removes the unprotected copper, leaving behind the circuit pattern defined by the photoresist. This method allows for precise and intricate designs essential for modern electronics, making it the preferred technique in PCB manufacturing.

While soldering is crucial for attaching components to a PCB after its creation, it is not involved in the fabrication of the board itself. Milling, although it can be used for PCB creation by mechanically removing copper, is less common compared to etching due to both cost and precision factors. Injection moulding is entirely unrelated, as it pertains to creating plastic parts rather than forming conductive pathways on circuit boards.