HDI PCB & High Interconnect PCB Manufacturing -- Hitechpcba
What is a high density PCB board (HDI PCB)?
The HDI board is based on the traditional double panel as the core board, which is made by continuously accumulating. This circuit board made by a continuous layer is also called the Build-Up Multilayer (BUM). Compared with the traditional circuit board, the HDI circuit board has the advantages of "light, thin, short, small".
The electrical connection between HDI's plate layer is achieved by conductive pores, buried holes, and blind holes. Its structure is different from ordinary multi -layer circuit boards. A large number of blind holes are used in HDI boards. HDI PCB uses laser direct drilling, and standard PCB usually uses mechanical drilling, so the number of layers and high width ratio often decreases.
HDI includes the use of fine features or signal traces and spaces of 0.003” (75 µm) or less and laser-drilled blind or buried microvia technology. Microvias allow the use of micro-interconnects from one layer to another within a PCB utilizing a smaller pad diameter creating additional routing density or reducing form factor.
High-density interconnect (HDI) PCBs are characterized by finer lines, closer spaces, and more dense wiring, which allow for a faster connection while reducing the size and bulk of a project. These boards also feature blind and buried vias, laser ablated microvias, sequential lamination, and via in-pads. As a result, a HDI board can house the functionality of the previous boards used. HITECH CIRCUITS is an HDI PCB manufacturer and provider in Shenzhen,
HDI PCB's advantages
1. Reduce PCB cost: When the density of PCB increases beyond the eight-layer board, it will be manufactured in HDI, and the cost will be lower than that of traditional complicated press-forming process.
2. Better reliability: Due to the thin thickness and the aspect ratio of 1:1, the micropores have higher reliability when transmitting signals than ordinary through holes.
3. Improves thermal properties: The insulating dielectric material of the HDI board has a higher glass transition temperature (Tg) and therefore has better thermal properties.
4. Improve RF interference / electromagnetic interference / electrostatic discharge (RFI / EMI )
5. Increase design efficiency: Micro-hole technology allows the circuit to be arranged in the inner layer, so that the circuit designer has more design space, so the efficiency of the line design can be higher.
HDI PCB Manufacturing Process
The overall process for manufacturing HDI PCB is essentially the same as for fabricating other PCB board, with notable differences for PCB stack-up and hole drilling. Since HDI boards generally require smaller drill holes for vias, laser drilling is usually required. Although laser drills can produce smaller and more precise holes, they are limited by depth. Therefore, a limited number of layers can be drilled through at a time. For HDI boards, which are invariably multilayer and may contain buried and blind vias, multiple drilling processes may be required. This necessitates successive layer boding to achieve the desired stack-up or sequential lamination cycles. Not surprisingly, this can significantly increase PCB manufacturing time and cost. HDI PCB fabrication is an advanced technology and therefore requires expertise along with specialized equipment like laser drills, laser direct imaging (LDI) capability, and special clean room environments. In order to efficiently manufacture high-quality and reliable HDI PCB products, you must understand the HDI board manufacturing process and coordinate with your HDI PCB supplier to implement good DFM (Design for Manufacturability) for HDI layout design. Therefore, not all board factories have the ability to do the HDI, but Hitechpcb can, we will be here to support our customer needs.
-Consumer Driven Technology
The via - in - pad process supports
More technology on fewer layers, proving that bigger is not always better. Since the late 1980's we have seen video cameras using cartridges the size of a novel, shrink to fit in the palm of your hand. Mobile computing and work at home have further promoted technology to make the computer faster and lighter, allowing consumers to do remote work from anywhere.
HDI technology is the main reason for these changes. The products do more, weigh less, and their bodies are smaller. Professional equipment, mini components and thinner materials reduce the size of electronic equipment, while expanding technology, quality and speed.
-Via in Pad Process
The inspiration from the surface installation technology pushed the restrictions of BGA, COB and CSP to a smaller square surface inch. The via in pad can be placed in the surface of flat land through the cushion process. The via is plated and filled with conductive or non-conductive epoxy resin, and then close and plat it to make it almost invisible.
It sounds simple, but there are eight steps to complete this unique process. Professional equipment and well -trained technicians followed closely to achieve perfect hiding.
-Via Fill Types
There are many different types of via fill materials: non -conductive epoxy, epoxy, copper filling, filling and electrochemical coating. All this leads to via buried in a flat land, and the land will be fully solders as normal land. Vias and mricrovias are drilled, blind or buried, plated, and then hidden under the SMT land. Processing vias of this type of Vias requires special devices and takes time. The process time of multiple drill cycles and controlling deep drills has increased.
-Cost Effective HDI
Although the size of some consumer products is reduced, quality is still the most important factor for consumers. Use HDI technology during the design process, you can reduce the 8-layer through-hole PCB to a 4 layer HDI Microvia technology packed PCB. The elaborate HDI 4-layer PCB wiring function can achieve the same or better functions as standard 8-layer PCB.
Although the Microvia process has increased the cost of HDI PCB, the appropriate design and decrease of layers of counting reduces the cost of the ingredients of the material, and the layer count is large.
-Laser Drill Technology
The smallest micro-vias can provide more technologies on the surface of the plate. Using a beam with a diameter of 20 microns (1 mil), this high impact can be cut through metal and glass to produce tiny via hole. There are new products, such as uniform glass materials, and they are low -loss layer pressure plates and low -dielectric constants. These materials have high heat resistance, can be used for lead -free components, and allows smaller holes.
-Lamination & Materials For HDI PCB Boards
Advanced multilayer technology allows designers to add other layers to form a multilayer PCB. Use laser drills to produce holes in the inner layer, and can be coated when pressed, imaging and etching. The process of this increase is called sequential construction. Hitechpcb HDI PCB manufacturing uses solid -filled VIA can better heat management, connect stronger connection and improve the reliability of the board.
The copper of the resin coating is a assistant with poor pores, with longer drilling time and thinner. Hitechpcb has ultra low contours and ultra thin copper foil, and its surface is fixed on a tiny nodule. This material has chemically treated and started chemical treatment and startup of the most fine and high quality lines and spacing technology.
The dry resistance of the layer pressure plate still uses heating scroll method to apply resistance to core materials. It is now recommended to preheat the material to the required temperature before the layer pressure process of the HDI printing circuit board. The preheating of the material can better apply dry resistance to the surface of the layer pressure plate, pull less calories from the heat roll, and keep the stable export temperature of the layer made products consistent. The consistent entrance and exit temperature cause less air clips under the movie. This is essential for the breeding of fine lines and spacing.
https://www.hitechpcba.com/hdi-pcb-manufacturer-high-interconnect-pcb-manufacturing
https://hitechcircuits.com/pcb-products/high-density-interconnect-pcb/