Refers to the direct growth process of local conductor lines with chemical copper layer on the surface of non-conductor substrate with the help of another inhibitor. The addition process for circuit boards can be divided into full addition, semi-addition and partial addition.
2. Back plate support plate
It is a thick circuit board (such as 0.093 ",0. 125"), which is specially used for plugging other boards. The method is to insert the multi-pin connector into the emergency through hole without soldering, and then connect the wires one by one in a winding way on each guide pin where the connector passes through the board. The universal circuit board can be inserted into the connector separately. Because the through hole of this special plate can't be welded, but the hole wall is directly clamped by guide pins, the requirements on quality and aperture are particularly strict, and the order quantity is not large. General circuit board factories are unwilling and difficult to accept such orders, and it has almost become a high-end specialized industry in the United States.
3. BuildUpProcess adds a layer method.
This is a new field of thin multilayer manufacturing. * Early enlightenment originated from IBM's SLC process and was put into trial production in Yasu factory 1989. In this method, on the basis of traditional double panels, two outer panels are coated with liquid photosensitive precursors such as Probmer52, and after semi-hardening and photosensitive decomposition, a shallow "Photo-Via" communicating with the next bottom layer is made. Repeatedly adding layers in this way will obtain the required number of layers for the multilayer board. This method can not only avoid expensive mechanical drilling costs, but also reduce its aperture to below 10mil. In the past 5 ~ 6 years, with the continuous promotion of manufacturers in the United States, Japan and Europe, various multi-layer board technologies that break the tradition and adopt layer-by-layer technology have made these BuildUpProcess famous and more than ten products have been listed. In addition to the above-mentioned "photosensitive pore-forming"; After removing the copper skin from the hole, the organic plate has different "pore-forming" ways, such as alkaline chemical etching, laser ablation and plasma etching. In addition, a new type of resin-coated copper foil coated with semi-hardened resin can be adopted, and a thinner, denser, smaller and thinner multilayer board can be made by continuous lamination. In the future, diversified personal electronic products will become the world of this really thin and short multilayer board.
4. Cermet Tao Jin
Ceramic powder and metal powder are mixed, and then adhesive is added as a coating, which can be printed on the surface (or inner layer) of the circuit board as a "resistor" to replace the external resistor in assembly.
5. Co-firing * * * combustion
This is a process of ceramic hybrid circuit board. The circuit for printing various precious metal thick film pastes on the surface of the small board is fired at high temperature. Various organic carriers in the thick film paste are burned off, leaving precious metal wires as interconnection lines.
6, cross, cross
When the gap between the intersections is filled with insulating medium, the three-dimensional intersection of two vertical and horizontal wires on the board is called. Generally, it belongs to this kind of "crossing" to add carbon film jumpers on the green paint surface of a single panel, or to wire up and down by adding layers.
7. Discrete circuit boards Discrete circuit boards and multi-line boards
That is to say, another way of saying multi-wiring board is to stick a round enameled wire on the board surface and add a through hole. The performance of this kind of multi-line board in high frequency transmission line is better than that of flat square circuit etched by general PCB.
8. Deuterium plasma etching layer increasing method
It is a build up process developed by Dyconex Company in Zurich, Switzerland. First, the copper foil at each hole on the board is etched, then it is placed in a closed vacuum environment, filled with CF4, N2 and O2, and ionized under high pressure to form a plasma with extremely high activity, which is used to etch the substrate at the hole, and tiny vias (below 10mil) appear. Its commercialization process is called DYCOstrate.
9. Electrodeposition of photoresist
Electro-resist, electrophoretic resist is a new type of "photoresist" construction method, which was originally used for "electro-coating" of metal objects with complex shapes, and only recently was the application of "photoresist" introduced. The charged colloidal particles of photosensitive charged resin were uniformly plated on the copper surface of the circuit board as an etching resist by electroplating. At present, it has been used in batch production in the direct copper etching process of inner plate. According to the different operation methods, this kind of ED photoresist can be placed on the anode or cathode respectively, which is called "anode electrostatic photoresist" and "cathode electrostatic photoresist". According to the different photosensitive principles, it can be divided into "NegativeWorking" and "PositiveWorking". At present, the negative ED photoresist has been commercialized, but it can only be used as a planar photoresist, and the through hole cannot be used for image transfer of the outer plate because of the difficulty in photosensitive. As for the "positive ED" which can be used as the photoresist of the outer plate (because it belongs to the photolysis film, the hole wall is not sensitive enough, but it does not affect it), Japanese manufacturers are still stepping up their efforts, hoping to launch commercial mass production and make the production of thin lines easier. The word is also called "electrothoretic fever".
10, flat conductor embedded circuit, flat conductor
It is a special circuit board with a flat surface and all wires are pressed into the circuit board. The method of single board is to etch off part of copper foil on semi-cured substrate by image transfer method to get the circuit. Then the circuit board is pressed into a semi-hardened board by high temperature and high pressure, and the hardening operation of the board resin can be completed at the same time, and the circuit board is completely flat when the circuit is retracted to the surface. Usually, it is necessary to etch off a thin copper layer on the surface of the circuit that has been shrunk, and then plate it with a nickel layer of 0.3 mil, a rhodium layer of 20 microinches or a gold layer of 10 microinches, so that the contact resistance can be lower and it is easier to slide when making sliding contact. However, this method is not suitable for PTH, so as to avoid crushing the through hole when pressing in. Moreover, this kind of board is not easy to reach a completely smooth surface and cannot be used at high temperature to prevent the circuit from being pushed out of the surface after the resin expands. This technology is also called EtchandPush method, and its finished board is called Flush-BondedBoard, which can be used for special purposes such as RotarySwitch and WipingContacts.
1 1, frit glass frit
In thick film (PTF) slurry, besides precious metal chemicals, glass powder is also needed to play a cohesive role when melting at high temperature, so that the slurry can form a solid precious metal circuit system on the green ceramic substrate.
12, the total addition process exceeds the addition process.
It is the practice of growing selective circuits on the surface of completely insulated circuit boards by electroless metal deposition (mainly chemical copper), which is called "total addition process". Another incorrect statement is the "FullyElectroless" method.
13, hybrid integrated circuit hybrid circuit
It is a kind of circuit which is printed on the thin substrate of a small ceramic chip with precious metal conductive ink, and then the organic matter in the ink is burned off at high temperature, leaving a conductor circuit on the board surface, and the surface can be bonded. It is the circuit carrier between printed circuit board and semiconductor integrated circuit device, and belongs to thick film technology. Early used in military or high frequency applications. In recent years, due to its high price, decreasing military use, increasing difficulty in automatic production, and miniaturization and precision of circuit boards, the growth of this hybrid has been greatly inferior to that of its early years.
14, interposer interconnect conductor
It means that between any two layers of conductors carried by an insulating object, some conductive fillers are filled in the place to be conductive, and this filler is called an insert. For example, the bare hole of multilayer board is filled with silver paste or copper paste instead of the orthodox copper hole wall, or the vertical unidirectional conductive adhesive layer and other materials belong to this kind of adapter board.
15, laser direct imaging, LDI laser direct imaging.
It uses the dry film without negative film to expose the plate and transfer the image, instead, it uses the computer to guide the laser beam to directly scan and photosensitive imaging on the dry film. Because it emits a single beam of parallel light with concentrated energy, the sidewall of the developed dry film can be made more vertical. However, this method can only work independently for each board, so the speed of mass production is far less than that of using negative film and traditional exposure. LDI can only produce 30 medium-sized boards per hour, so it can only occasionally appear in prototype proofing or high-priced boards. Because of the high innate cost, it is difficult to promote it in the industry.