吃瓜tv / Metal substrate engineering
Metal Core PCB Manufacturing Process
See how the circuit, insulating layer and metal base are handled from drawing review to release. Follow the steps and the checks that distinguish a thermal board from an ordinary fabrication job.
Get a project quoteBare boards or assembly scope 路 Send preliminary files if the stackup is still open.
The metal core PCB manufacturing process, in order
A representative simple IMS route is: engineering review 鈫� material verification 鈫� copper imaging 鈫� etching and inspection 鈫� machining 鈫� solder mask 鈫� surface finish 鈫� profiling 鈫� electrical/isolation tests 鈫� final inspection and packaging. The traveler can change with laminate, finish, holes and panel design.
This page describes bare-board fabrication. Component purchasing, solder paste printing, placement, reflow and functional testing belong to the PCB assembly process.
Metal Core PCB Process Walkthrough
From released files to a finished bare board
01 / Review the drawing and acceptance scope
Confirm the circuit layers, base metal, dielectric, copper weight, outline, plated and non-plated holes, insulation and testing. Resolve whether a thermal contact must be isolated or directly connected to the metal.
Check: Approved construction, revision and test scope.
02 / Confirm the laminate and material route
For many simple single-circuit-layer IMS boards, fabrication starts with a purchased copper-clad insulated metal laminate. Incoming review establishes material identity and condition. Bonding or custom multilayer work requires its own qualified route; lamination is not automatically repeated for every simple board.
Check: Material grade, thickness and traceability information.
03 / Prepare the surface and image the circuit
Prepare the circuit copper for the selected imaging process. Apply the image and expose/develop it using the approved artwork. Alignment and surface condition affect the pattern that survives etching.
Check: Artwork alignment and developed-pattern inspection.
04 / Etch the copper and inspect the circuit
Remove unprotected copper to form the conductor pattern. Copper thickness affects etch compensation and achievable line/space. Inspect for opens, shorts, residual copper and excessive etching before subsequent coatings hide the detail.
Check: Circuit geometry inspection against the approved artwork.
05 / Drill and machine the agreed features
Create mounting holes and other features using the planned route. Control burrs and protect the dielectric. Insulated plated holes require special base clearance and insulating construction before the barrel can be formed; they are not ordinary holes plated against exposed metal.
Check: Hole size/location, burr and isolation-construction checks.
06 / Apply and inspect solder mask
Apply the specified mask, expose/develop and cure it to the material process. Check pad openings, registration, coverage and adhesion requirements. White mask for LEDs needs a specified material if optical performance is important.
Check: Mask opening, registration and curing controls.
07 / Apply the surface finish and identification
Finish the exposed circuit pads as ordered. Review assembly compatibility, storage and finish acceptance. Apply identification so the board and revision can be recognized through manufacturing and assembly.
Check: Finish coverage and identification checks.
08 / Profile, deburr and check mounting surfaces
Route, score or otherwise separate the outline according to the approved method. Protect copper clearances and the dielectric at edges. Inspect the outline and the contact surface needed by the cooling arrangement.
Check: Dimensions, edge quality and relevant flatness checks.
09 / Test circuit connectivity and defined isolation
Check circuit continuity and unwanted connections. Separately perform the agreed circuit-to-base isolation or proof test when required, with defined voltage, duration and leakage/trip limits. A material breakdown figure is not a production test instruction.
Check: Identified electrical test scope and recorded results as ordered.
10 / Final inspection, protection and release
Review the final visual and dimensional criteria. Package to protect solderable surfaces, exposed metal and edges; use the agreed moisture, cleanliness and identification requirements. Release the correct revision with the ordered documents.
Check: Final inspection, packaging and shipment identification.
Where the process changes: holes, DTP and multilayers
| Construction | Additional decisions |
|---|---|
| Simple one-circuit-layer IMS | Purchased laminate, circuit pattern, non-plated mechanical holes and defined isolation. |
| Insulated plated through holes | Base clearance, insulating fill/barrier, plating route and circuit-to-base verification. Exact sequence is process-specific. |
| Direct thermal path | Package pad geometry, thermal-contact formation, electrical potential and exposed-base treatment. |
| Multilayer metal-core PCB | Stackup bonding, layer registration, hole construction and the actual thermal path through additional layers. |
| Assembled MCPCB | Thermal profile, solder coverage/void acceptance where relevant, test access and product cooling validation. |
Use the copper-base / DTP guide when the thermal contact is direct, or the aluminum PCB guide for conventional LED/IMS design.
Process risks and the evidence to request
| Observed problem | Possible contributors to investigate | Verification to agree |
|---|---|---|
| Open / short circuit | Imaging, etching, contamination or handling. | Artwork comparison and circuit electrical testing. |
| Circuit-to-base leakage | Dielectric damage, contamination, burrs or inadequate hole/edge construction. | Construction review and defined insulation/proof-test method. |
| Poor cooling after assembly | Pad soldering, dielectric, interface contact, mounting or sink capacity. | Thermal-path review and an assembled-product test under known conditions. |
| Warping / poor contact | Material balance, machining, assembly heating or fastening. | Flatness and mounting checks appropriate to the drawing. |
| Mask or finish defects | Preparation, material application or process control. | Visual coverage, registration and agreed material/finish acceptance. |
These are diagnostic possibilities, not a root-cause determination from appearance. Equipment images support the process explanation; traceable inspection or test records support acceptance. Read quality and supplier-review information and the PCB equipment page when preparing a supplier review.
What your fabrication notes should define
- Base grade and thickness, dielectric identification/thickness and finished circuit copper.
- Hole types, circuit-to-base relationships, mounting features and relevant edge treatment.
- Finish, mask, legend, outline and revision control.
- Applicable acceptance document/revision and any construction-specific requirements.
- Circuit test coverage and any isolation/proof test with complete conditions.
- Thermal validation scope: material data, a bare-board characterization or an assembled-product test are different deliverables.
Check dimension and copper-dependent geometry against the metal-core manufacturing capability tables. Do not copy a single minimum spacing or proof-test voltage to every laminate and copper construction.
Manufacturing process questions
Does every metal-core board require a new lamination cycle?
No. Many simple IMS boards begin with a purchased copper-clad metal laminate. Custom bonding and multilayer constructions have additional material and lamination steps defined by their route.
Why do drilled holes need special attention?
The base is conductive. A plated barrel, lead or burr can create an unintended electrical connection unless the construction provides the required separation or an intentional connection.
Is thermal conductivity measured on every finished PCB?
Do not assume that. Material characterization, production inspection and product thermal validation are different activities. Define the required evidence and sampling in the order.
What is the difference between circuit test and hi-pot?
Circuit testing checks intended and unintended circuit connectivity. A dielectric proof test stresses a specified insulation path under defined conditions. One does not automatically replace the other.
How long does manufacture take?
The route, material availability, quantity, machining and test requirements determine the schedule. Request a delivery commitment against the reviewed files rather than relying on a generic number of days.
Can the same process be used for iron, aluminum and copper?
They share some circuit-fabrication concepts, but material preparation, machining, protection, bonding and acceptance requirements can differ. Use a grade- and construction-specific traveler.
Turn the process requirements into a manufacturing brief
Send the released files, or clearly mark preliminary data. Include the points below so the quote describes the board you actually need.
- Fabrication data and drawing revision.
- Material/stackup, hole and isolation details.
- Quantity, required dates, finish and packaging needs.
- Required inspection, electrical/isolation tests and supporting documentation.
Email sales@raypcb.com if you prefer an email discussion. For base-material selection and an early budget, use the metal-core PCB manufacturing hub.