Different to acid etching – where an acid is used to remove the copper – the alkaline etching process uses a base etchant (e.g. ammonia sulphate) to etch away unwanted copper from the PCB.
The base copper is the copper layer on the raw PCB material. On the outer layers, this forms the initial point for subsequent coatings of copper. If, for example, the customer requires a copper thickness of 35 μm, the base copper will be 18 μm. The remaining 17 μm will be added during the through-hole plating process.
The base material is the raw material. Base materials are available with different thicknesses, base copper thicknesses, electrical and physical properties to meet a number of PCB application requirements.
BGA is the acronym for Ball Grid Array. This refers to components that do not make connections to the PCB through conventional pins, but by means of ball-shaped connections. There is a space saving advantage here; a higher number of connections are possible as the connections are located underneath the component.
Blind vias are vias, which are connect an outer layer to either an inner layer, or a number of inner layers, but do not pass through the entire PCB and are therefore not visible from one side.
Buried vias are buried drill holes, which are not visible from outside. Before the multilayer pressing process begins, buried vias are drilled into the multilayer core. Then they get plated and filled.
The acronym CAD means Computer Aided Design. This is the computer-assisted creation of a design. In PCB manufacture, the term refers to the creation of PCB layouts.
CAM means Computer Aided Manufacturing. In the PCB manufacture, this refers to data preparation for production, which takes place after the CAD design of the PCB has been completed.
Coating describes the application of surface finishes on your PCB. For example with electroless Ni / immersion Au, chemical tin or HAL lead-free. Coating with lacquers (e.g. solder resist) can also be meant here.
A component drill is a plated through hole, into which components can be placed. These holes are generally bigger, so that the pins of the components can be inserted.
Conductive pattern is the generic term for the structures of a layout.
Copper foil, copper thickness
The copper foil is bonded to the base material. On the outer layers, it is important to be clear about whether the copper thickness is the base copper thickness or the finished copper thickness.
The term "copper layer" refers to the individual conductive layers of your PCB layout which will be manufactured from copper.
Copper outer layer
The copper of the outer layers of your PCB consists of the base copper and the copper that is applied during the production processes. If, for example, you order 35μm copper, we start with 18μm copper foil on the outer layers. The remaining copper is applied during the manufacturing process of the PCB.
The copper surface usually refers to the areas of your PCB that are covered with copper. Depending on the layout, copper balancing can be advisable (i.e. additional copper to keep the copper distribution in the layout as even as possible).
Copper plating is the copper, which is applied to a PCB. In the WEdirekt configurator we always refer to the finished copper.
From a technical point of view, "corrosion" means the reaction of a material with its environment, causing a change or impairment of the material. Rust is a classic example of corrosion. This process can also appear on the surface of PCBs. Please note the "lifetime" of our surfaces according to our specifications.
We can deliver a PCB in two ways: as single PCBs or as delivery panels. A delivery panel is a board with more than only one outline. This can be a simple delivery panel frame or delivery panel made up from several individual PCBs. We always supply these delivery panels as an entire panel, i.e. we do not separate the boards.
In the WEdirekt Online-Shop, you can choose either a "Delivery panel from data" or "Delivery panel using online configurator".
Delivery panel tab, break-off tab, delivery panel frame
A tab is something which keeps the PCB in contact with the surrounding material after routing. It is mainly used in delivery panels to connect the boards with each other and to the panel frame.
The design or layout (file) is the designed PCB layout data, which is necessary for the production of your PCB.
A dimension can be information within the layout data or an additional document (e.g. a PDF). The dimension describes the dimensions of a PCB. In case of questions, such a document can be very helpful for the PCB manufacturer.
A double-sided PCB is also called a 2-layer or DS-board. A double-sided board is a PCB with two copper layers, one on each side.
The drill diameter is the diameter of the drill tool. In PCB production drill tools of 0.10mm up to 6mm are available.
Drilling small holes is a relatively complex process, but the through hole plating of such small holes can be even more challenging. This is the reason why many PCB manufacturers do not offer drill holes of less than 0.20mm. Holes which are larger than 4.00mm are often routed. This can be beneficial to the hole quality, since large drill tools often cause more burr than a milling tool. More information can be found here.
The ECO stencil is our lowest cost stencil type. It is a stencil with a size of max. DIN A4 with up to 1.000 pads.
We offer this for SMD stencils having a self-tensioning frame system. In this case, the edges of the metal stencil are crimped. This minimizes the risk of injury from sharp edges. As a positive side effect, the stability of the metal stencil increases.
The electrical test is carried out to ensure the correct electrical connections are present between the structures and the layers. The PCB is tested for short circuits and open circuits. Please be aware that the test is based on the connections present in your PCB layout, so if you have a short circuit in your original data, this will not be recognised as a short circuit in the e-test.
Electroless nickel immersion gold
Electroless nickel immersion gold (ENIG) is a PCB surface finish. It is very planar, aluminium wire bondable, has a good solderability and a long storage life. Its disadvantage is the relatively high process costs. More information on surfaces can be found in our specifications.
Etching technology is a highly precise and strictly controlled subtractive process, used for the production of complex metal parts with the finest details. The final structuring of the copper features in the PCB is made with etching technology.
The structures of your PCBs are imaged during the manufacturing process "exposure". A similar process is also used when applying the solder resist.
Extended Gerber Format is the preferred format of many PCB manufacturers (also from Würth Elektronik). We of course also work with other formats.
Fiducials are usually used for the exact alignment of the PCB or stencil for the assembly.
During final inspection the quality of the PCBs is inspected and any potential manufacturing defects will be detected.
Flexible PCBs differ from standard PCBs due to their flexibility caused by the use of very thin material (polyimide).
GC Preview is a software used to create layout data. More information can be found here.
HAL is the acronym for "Hot Air Levelling", i.e. hot air tinning. This is a method to tin PCBs. HAL lead-free is a lead-free tinned surface finish on the PCB. This surface allows you to solder and to store your PCBs for a long period of time.
The hard gold surface finish consists of an underlying nickel layer and an overlying gold layer. The gold is electroplated. The typical gold layer thickness is between 0.5μm and 1.2μm.
The acronym HDI refers to "High Density Interconnect". HDI PCBs are characterised by very fine structures and small holes. In times of miniaturisation, HDI Microvia PCBs become more and more crucial.
Inner layers are copper layers, which are present inside the PCB, i.e. copper layers that are not the top layer or the bottom layer.
The insulation spacing describes the spacing between lines, pads and plated holes.
IPC (Institute of Printed Circuits) is an institute that produces standards for PCB manufacturing.
The term "laser" is often used when talking about "HDI Microvia" technology, as the microvias are created by a laser drilling process.
This term refers to the production of our stencils. The stainless steel stencils are always cut with a laser. This applies to both, the contour and the perforations within the template.
The layout file is the data we need to produce your PCB. We can process all common data formats in Extend Gerber, Altium, EAGLE, ODB++, and Target 3001.
LDI refers to Laser Direct Imaging, the direct laser exposure. With this process, PCB layout features can imaged directly, without the use of a film.
Copper planes are areas in the PCB layout which consist of a complete copper surface
Mechanical drilling means classical drilling, i.e. the introduction of a hole into the PCB by means of a drilling tool.
The term "mechanics" refers to different mechanical processes like drilling, routing or scoring.
The layer count refers to the number of copper layers in the PCB design. At WEdirekt, you can get 1, 2, 4, 6, 8, 10, 12, 14 and 16 layer boards.
The top and bottom layers are also known as outer layers of the PCB. These layers are visible and accessible. Only the outer layers can later be assembled with components.
The pad is a copper surface which is either directly soldered onto or in which a hole is created. The circulating residual material around the hole is known as annular ring.
Pad optimization is applied to our stencils (if required). It is often advantageous if the pad openings in the stencil are smaller (or even larger) than the associated pad in the conductor pattern. In this case, we can optimise the paste data according to your wishes.
The pad reduction is a possible variant of pad optimization. The pads are reduced by the desired value.
A panel frame can be added to the PCB, if required. It is often used as an aid in assembly.
Panel utilisation refers to the amount of the production panel that contains PCBs. The better the panel utilisation, the less waste that is created. This is the great advantage of WEdirekt. In the pooling process, we place different orders on one production panel and, by doing so, we ensure an optimal panelisation, which leads to low prices.
The paste data is necessary for the stencil production. Important: we do not create the paste data. If it is present in the single layout of your PCB, we will create the paste data in panel. However, we do not create it ourselves (from the copper or soldering pads).
The PCB name is the name or part number of the PCB. Our advice: if you add the name of the PCB onto the PCB, then use the same reference on the order and when naming the PCB production files in your dataset.
The size of the PCB depends largely on the purpose of your PCB. More about the possibilities at WEdirekt can be found here.
We offer polishing as an optional addition to our stencils. When polishing, both the surface of the stencils and the pad walls are refined.
The reason for the favourable prices at WEdirekt is the type of production. PCB orders with matching technical characteristics are produced together on a production panel. This optimises the production utilisation and saves costs. The PCB manufacturer thus uses the "pool" of existing orders and is able to produce in a cost-effective and efficient way through the "pooling process".
Prepreg is an abbreviation for pre-impregnated. This refers to the fiberglass material, which is pre-impregnated with a resin. The resin serves to bond the copper layers of the PCBs together by means of the production step "pressing".
The term "production data" refers to the layout data, which has been prepared by us for production.
The production panel is the panel of material from which your PCBs are created. As a PCB manufacturer, we often speak about the usable area on a production panel. This is the area of the panel which can be used to produce the ordered PCBs. There can easily be a number of PCBs or delivery panels on one production panel.
PTH, plated through holes
In PCB manufacture, the drills that contain a coating of copper are referred to as plated through holes.
During the routing process the required outline of the PCB is created and the PCBs are removed from our production panel. Routing is a mechanical process and there are a number of different sized routing tools available. The most common router is 2.00mm. Smaller routing tools down to 0.5mm are also possible, but using smaller routing tools can have an impact on the PCB manufacturing costs. For example with smaller routing tools it may not be possible to rout a number of panels simultaneously.
Compared to scoring, routed edges are characterised by a clean cut and smaller tolerances. However, routing is one of the most time-consuming steps during PCB production. This should be considered if you order online samples, which later will go into larger series volumes.
The resulting distance between the residual material and the PCB after routing. The width of the routing channel can vary depending on the diameter of the routing tool.
The specified outline, which defines the shape of the final product. The contour of the final product is separated from the remaining material along the centre of this line.
A small overhang that remains at the entry and exit points of the cutter. This can be removed by filing.
The scoring program defines the scoring positions. The mechanical department works according to this program.
Self-tensioning frame system
The term self-tensioning frame system relates to stencils. If you use such a system for assembly, you need a suitable stencil.
A short circuit occurs when two connections at different potentials unintentionally meet. This can be caused by a layout error. However, a short circuit may also occur during PCB manufacture or further processing of the PCBs. For this reason, we always include an e-test for our multilayer boards. Short-circuits caused by production can thus be virtually excluded. See also e-test.
The silkscreen is a marking method for PCBs. It is also called legend print or annotation print. The silkscreen print is applied by means of a screen printing process or by full-surface printing. For the latter, no screen is required, which makes this process suitable for small quantities.
A single PCB is a PCB which is supplied with no delivery panel or handling frame. Only the contour and internal cut-outs will be routed.
The SMD stencil is used for the assembly of PCBs. WEdirekt offers all common stencils: simple ECO stencils, which are perfect for manual assembly, as well as SMD stencils for self-tensioning frame systems or frame stencils. You can find all available stencil types in our stencil configurator.
The solder pad is a solid copper pad or the annular ring around a plated through hole on which the component is soldered.
The solder resist serves different purposes on the PCB. It protects against corrosion and mechanical damage. It prevents short circuits and the wetting of certain surfaces during soldering. It insulates components againstfrom the circuit board surface and improves the dielectric strength of your PCB. You can find more information about the solder resist here.
In printed circuit board terminology, the term "spacing" can refer to various things. For example, it can be the area between two tracks, between two copper features or between the layers of the multilayer stack-ups, etc. In most cases, the type of spacing in question can easily be ascertained from the context.
The stencil size can vary, depending on the type of stencil required. If you are using a self-tensioning frame system, the size is already defined. If you need a simple stencil without edge tooling holes for mounting, it is recommended to determine the size using the corresponding PCB. We recommend an addition of 30mm.
The tool diameter is important for the drilling process. To reach your requested final diameter, we drill 0.15mm larger on plated through holes. During the production process we put copper in the hole to reach the final thickness.
The track spacing is the spacing between two tracks or between track and pad. This is also known as insulation distance.
UL marking is an official marking / certification that confirms that we as a PCB manufacturer are safety tested with regard to electrical fire and accident risks. The certificate is issued by Underwriters Laboratories Inc. You can find our certificate here:
A via is a plated through hole, which connects the layers with each other. A via is a plated through hole without THT assembly.