Inside Our PCB Factory
Our PCB factories in Huizhou and Wuxi are purpose-built for defense and military electronics, aerospace & aviation, security & radar systems, as well as automotive, industrial, UAV and medical applications.With 30000 m² shop floor and 100000 m²/month capacity, we focus on high-frequency, high-speed and special-material PCBs that support mission-critical and long-lifecycle programs.
Factory Floor Area
PCB Capacity
PCB Plants (Huizhou & Wuxi)
PCB Factory at a Glance
Multilayer & Quick-Turn Center
Location: Huizhou, Guangdong, China Focus: 2–128 layer multilayer PCBs, prototypes & small batches Typical applications: industrial control, power boards, automotive ECUs
HDI & High-Frequency Center
Location: Wuxi, Jiangsu, China Focus: HDI, high-frequency RF/microwave, rigid-flex and special materials Highlights: laser microvias, impedance-controlled stack-ups, complex processes
PCB Production Video
How a PCB Is Made in Our Factory
From inner layer imaging to final electrical testing, every panel goes through a tightly controlled, IPC-compliant production flow. Below is a simplified view of the main steps.
PCB Substrate Preparation & Pre-Treatment
Premium FR-4 and other base materials are incoming-inspected and coded by batch. Automatic panel cutting and edge trimming ensure accurate dimensions and clean surfaces, laying a solid foundation for copper cladding and imaging.
Inner Layer Imaging & Etching
Dry film lamination and exposure precisely transfer the circuit pattern onto the inner-layer copper. Chemical etching then removes unwanted copper, leaving only the designed fine traces and pads to form high-precision inner circuits.
Inner Layer Inspection & Oxide Treatment
After inner-layer patterning, 100% AOI (Automated Optical Inspection) checks for opens, shorts, nicks and other defects. Brown/oxide treatment increases copper surface roughness and improves interlayer adhesion, ensuring reliable multilayer lamination.
Multilayer Lamination & Stack-Up
According to the designed stack-up, inner cores and prepregs are aligned and laminated under controlled temperature and pressure. For HDI, buried vias or resin-filled structures, via filling and related processes can be integrated at this stage to realize complex 3D interconnections.
Drilling & HDI Microvia Formation
High-speed CNC drilling machines create through-holes and tooling/mounting holes with tight positional accuracy and smooth hole walls. For HDI boards, laser drilling forms microvias and blind/buried vias, enabling high-density interconnects and fine-pitch BGA fan-out.
Hole Metallization & Copper Plating
Chemical copper (PTH) first deposits a uniform conductive layer on the hole walls, followed by electrolytic copper plating to thicken copper in holes and on surfaces. Stable PTH and plating-line control ensure sufficient copper thickness and reliable electrical continuity in all vias and through-holes.
Outer Layer Imaging & Etching
Dry film is again laminated on the outer copper surface and exposed to define the final trace and pad geometry. Pattern plating and etching then form the finished outer-layer circuitry, completing the PCB’s conductive network as per design.
Solder Mask & Legend Printing
Solder mask ink is coated and cured on the board surface to protect copper, prevent solder bridging, and enhance corrosion resistance and insulation. Silkscreen printing adds component legends and markings to support assembly positioning, material management and product traceability.
Surface Finish (OSP / ENIG / ENEPIG, etc.)
Depending on application and assembly process, pads receive OSP, ENIG, ENEPIG, HASL or other finishes. The chosen surface finish must balance excellent solderability and flatness with storage life and long-term reliability requirements.
Profiling, Depanelization & Final Cleaning
CNC routing and V-cut operations accurately profile and depanel the boards, ensuring outline dimensions and mounting holes match the drawings. A final cleaning step removes flux residues and particulates, providing a clean surface for assembly and reliability testing.
Electrical Testing & Impedance Verification
Flying probe or bed-of-nails testing checks every PCB for continuity and isolation, eliminating open circuits and shorts. For high-speed and high-frequency designs, impedance testing, X-ray inspection and microsection analysis can be performed to verify internal connections and structural reliability.
Final Inspection, Packaging & Shipment
Final quality control (FQC) verifies appearance, dimensions, markings and quantities to ensure full compliance with customer documentation. Approved boards are vacuum-packed with desiccant and protected by outer cartons, reducing moisture uptake and mechanical damage during transportation and storage.
Manufacturing & Quality Teams Behind Every PCB
Behind every panel, there is a cross-functional team including process engineers, line supervisors, equipment technicians and quality engineers.
Process Engineering – defines stack-up, process window and DFM guidelines.
Production – executes standard work instructions and real-time SPC control.
Quality – monitors key checkpoints and leads 8D problem solving when needed.
How We Build Quality into the Factory Floor
Quality is not only a final inspection step – it is built into every process in our factories.
Management systems: ISO 9001, IATF 16949, AS9100, ISO 13485, GJB 9001C-2017 and more.
In-line control: AOI for all inner/outer layers, automatic plating control, solder mask and thickness checks.
Final assurance: 100% electrical test for volume orders, reliability tests available on request.
Visit Our PCB Factory or Arrange a Remote Audit
Many automotive, medical and defense customers start with a factory audit before launching new programs. We support both on-site visits and remote video tours, including live walkthroughs of key processes, quality labs and reliability testing.
World-class PCB & PCBA manufacturer focused on high-frequency and high-reliability boards for defense, aerospace, automotive and industrial electronics.
You can unsubscribe at any time with a single click.
Copyright © 2025 UltroNiu Electronics Group All Rights reserved.