Design rules for a ceramic circuit board depend on the substrate, metallization, metal thickness, hole process and singulation method. A line width or via diameter found in a generic guide is not a production limit for every combination. Use this page to prepare a drawing and identify the questions a manufacturing review must answer. When ready, send the controlled drawing for quotation.
Begin with the required electrical insulation, heat flow, assembly temperature and mechanical loading. Then shortlist the ceramic grade and conductor route. Alumina, aluminum nitride and silicon nitride are material families, not interchangeable grades. The material comparison is a starting point; request the selected grade’s current datasheet and conditions for any property used in a calculation. A DBC copper pattern, a plated DPC pattern and a printed thick-film pattern have different feature and edge constraints. Our DBC versus DPC guide explains the basic trade-off. Confirm that the chosen material and process combination is available for the specific drawing.
Gerber X2 attributes can convey layer and object functions in fabrication data; they do not replace a drawing that defines ceramic grade, thickness and acceptance criteria. See the Ucamco Gerber documentation and IPC’s design data standards.
Check minimum conductor width and spacing against the selected metal thickness and patterning route. Thick metal changes the amount of lateral etching and the attainable corner shape. Show current-carrying paths and local heat sources, but calculate current and temperature rise for the full assembly rather than assigning a universal amps-per-trace value. Rogers’ DBC/AMB design discussion illustrates why layout, copper balance, thickness and panel arrangement affect bending. Its dimensions and process limits describe Rogers’ products, not this site’s capability.
Mark the purpose of every hole: mounting, registration, electrical connection or thermal path. State finished diameter and tolerance, required metal coverage or fill, and proximity to edges and conductors. A hole that is possible to form is not automatically suitable for metallization or a particular reliability requirement. Use the laser drilling overview for process questions, then request a part-specific check of diameter, pitch and edge distance.
Identify whether dimensions apply before or after singulation and where chips or cracks would interfere with assembly. Ask how the part will be supported during patterning, separation, inspection and shipment. Ceramic is brittle; unsupported edges, mounting loads and abrupt features deserve a specific mechanical review. Provide the intended clamping or fastener arrangement if the board is mechanically loaded.
Specify the actual attach method for each pad: solder, wire bond, sinter, adhesive or contact. A finish chosen for solderability is not automatically a qualified wire-bond surface. Confirm surface preparation, compatibility with the selected metallization and acceptance test with the assembler. The surface finish guide gives the questions to ask, but the final finish stack should be agreed in the drawing.
For a simple, uniform slab carrying one-dimensional heat flow, ceramic-only thermal resistance is R = t/(kA), where t is thickness in metres, k is thermal conductivity in W/(m·K), and A is heat-flow area in square metres. The result is in K/W. This is a screening calculation: patterned metal, lateral spreading, die attach, interface material and heat sink add effects the expression does not capture. See our thermal conductivity and resistance guide. NIST discusses the one-dimensional definitions and measurement basis in its thermal conductivity technical paper.
For electrical isolation, specify operating voltage, transient and test conditions, environmental exposure and the relevant system standard. A ceramic datasheet’s dielectric strength is a material test result. It is not, by itself, a working-voltage rating for a patterned board or assembled product.
Before release, record the selected material grade, conductor route, finish, critical dimensions, hole functions, inspection conditions and unresolved deviations. Ask the fabricator to identify each proposed change against the drawing revision. Send your drawing for a feasibility and quotation discussion; include the operating conditions so the design can be reviewed in context. Published examples on this page are guidance, not guaranteed process limits.