Process flow of single-sided PCB board: cutting and edge grinding → drilling → outer layer graphics → (full board gold plating) → etching → inspection → silk screen solder mask → (hot air leveling) → silk screen characters → shape processing → testing → inspection. Double sided PCB board process flow: cutting and grinding edges → drilling → copper sinking and thickening → outer layer graphics → tin plating, etching and tin removal → secondary drilling → inspection → silk screen solder mask → gold-plated plug → hot air leveling → silk screen characters → shape processing → testing → inspection.

Prepare data: including substrate, conductive data, insulation materials, etc. Design circuit diagram: Design a multi-layer PCB circuit diagram according to the requirements. Creating Inner Circuit: Transfer the circuit diagram onto the inner board and then etch the circuit. Making outer circuit: Cover an insulation layer on the inner board, and then design and etch the circuit on the outer layer. Layering: Stacking multiple layers of boards together and then laminating them to tightly bond the circuits of each layer. Drilling: Drilling holes on multi-layer boards to connect the layers together. Welding components: Welding electronic components onto a PCB. Quality inspection: Check the quality of multi-layer PCBs to ensure they meet the requirements. Packaging: Pack multi-layer PCBs for transportation or use.

Substrate production: The substrate mainly consists of copper foil, adhesive, and PI (polyimide), and can be classified into single-sided and double-sided substrates. Data with only one copper foil is considered a single-sided substrate, while data with two copper foils is considered a double-sided substrate. Exposure: The transfer of circuit graphics onto the board through the action of a dry film is usually carried out using a photosensitive method. After the exposure is completed, the circuit of the FPC board is basically formed. PI Etching: Under certain temperature conditions, etching solution is uniformly sprayed onto the surface of copper foil through a nozzle, undergoes oxidation-reduction reaction with copper, and then undergoes film removal treatment to form a circuit. Hole opening: The purpose of hole opening is to form the original conductor line and the interconnection line between layers. Hole opening technology is commonly used for the conductive connection between the upper and lower layers of double-layer FPC. Testing: After the production is completed, it is necessary to conduct testing to screen out unqualified FPC boards and ensure that the FPC maintains good performance in application.

Board preparation: Select appropriate soft and hard data for cutting and trimming. Hot pressing: Overlay soft and hard data in a certain order and place them in a hot press machine for heating and pressing. Pressure control: Based on the characteristics and requirements of soft and hard data, control the pressure of the hot press machine to avoid unstable sheet quality caused by excessive or insufficient pressure.