Printed Circuit Board Materials

Printed circuit board (PCB) materials are the substrates used to make printed circuit boards, which are essential components of many electronic devices. PCB materials have four basic requirements: good electrical conductivity, good thermal conductivity, good mechanical properties, and good chemical stability. There are several different materials that can be used to make printed circuit boards, each with its own unique properties and advantages.

Material for Rigid FR4 PCB

Standard FR-4 Materials

Hitechpcb materials are provided as standard FR-4 for rigid circuit boards with options for mid and high glass transition temperature.

Some of the materials include KB-6160 as a standard FR-4, KB-6167, S1000-2, IT180A, 370HR, FR408 for high Tg.

These FR-4 materials are derived from high-grade resin and glass fiber laminates with different thickness options.

You will find these FR-4 materials used with copper films for a variety of applications requiring different power needs.

Additionally, you find they possess strong mechanical properties such as flexural strength with impressive thermal and electrical properties.

Their resistance to material changes on exposure to different temperature values provides stronger joints and stability.

Material for High Speed PCB

N4000-13 EP High-Speed Multifunctional Epoxy Laminate & Prepreg

Nelco N4000-13 EP is an enhanced epoxy resin system engineered for today’s lead-free requirements where multiple solder reflow at temperatures approaching 260ºC are required. N4000-13 EP provides enhanced thermal reliability without compromising the electrical and signal loss properties that have made the Nelco N4000-13 product family the industry standard for demanding high speed / low loss designs. N4000-13 EP SI is excellent for applications that require optimum signal integrity and precise impedance control, while maintaining high CAF resistance and thermal reliability.

Nelco 4000-13 VS FR408HR VS Megtron 6

The design of interconnect that support data rate exceeding 50 Gbps is necessary to support Terabit backplane systems. In order to predict and optimize the performance of high-speed links operating at 50 Gbps and beyond, it is essential to accurately model and characterize the interconnect systems. The models of interconnects have to be broadband and include high frequency effects that were not critical at that data rates in the range of 10 to 20 Gbps . For higher data rates, very careful modeling of signal propagation in PCB and package traces requires proper identification of the conductor and dielectric frequency-dependent properties over extremely wide frequency band. In addition, 3D modeling and characterization of transition structures are essential to understand and optimize the wave propagation and minimize mismatch across various transition structures such as via and BGA at the interface between package and PCB.

Low-loss laminates such Megtron 6 from Panasonic, FR408HR from Isola Group, and Nelco 4000-13 EPSI from Park Electrochemical Corp. are expected to be key enablers to design boards to run at higher data rates. These laminates offer much more stable dielectric characteristics and have considerably less loss at high frequencies. To investigate the effect of low-loss laminates and see the impact of surface roughness, dielectric properties, glass weave effects, several boards with Megtron 6 with Hyper Very Low Profile (HVLP) finish and Reverse-Treated Foil (RTF) finish, Nelco 4000-13 EPSI with RTF copper foil and standard glass weave, Isola FR408HR with RTF copper foil and standard glass weave. It shows typical electric properties of these low-pass laminates that are studied in this paper and of typical FR-4 board for comparison

The manufactured boards were cross-sectioned to accurately verify all the dimensions of the transmission lines. It shows the cross-section of the board with Isola’s FR408HR, Nelco N4000-13 EPSI, Megtron 6 with RTF and HVLP finishes. The dimensions for the conductor thickness, width, the trace spacing, and the top and bottom layer heights are all marked in microns (µm)

Scattering parameter measurements are taken with a 4-port 67-GHz vector network analyzer (VNA) using high-frequency probes with 200 um-pitch GSSG configuration and high-frequency snap-on connectors. The two set of differential nets with 6-in. and 12-in.long traces for FR408HR, Nelco N4000-13 EPSI, Megtron 6 with RTF, and HVLP finish are measured. The measured differential and common mode insertion loss for the 12 in.traces of the four boards are show. The simulated insertion losses of similar structures using FR4 boards are also plotted for comparisons. The plots show attenuations that agree with the electrical properties of these laminates given in Table I. The measured differential insertion loss of the Megtron 6 with HVLP finish shows about 2 dB improvement over that of the Megtron 6 with RTF finish at 25 GHz. The Megtron 6 with HVLP finish also shows about 4 dB and 6 dB improvements over Nelco N4000-13 EPSI and FR408HR, respectively. The 12-in. trace in Megtron 6 with HVLP laminate shows about 20 dB less loss when compared to similar trace in FR-4 board

The differential group delays of the 12-in. traces are calculated from the measured four-port S-parameters. The delays per inch of the four boards are plotted as functions of frequency. The simulated group delay for FR-4 board is also included in the plots. The Nelco N4000-13 EPSI shows the smallest delay as expected from the dielectric constant value of this laminate given. The typical FR-4 shows the longest delay as predicted from its higher dielectric constant.

Time-domain simulations are also performed using the measured S-parameters to calculate the single-bit response for an excitation of a pulse with amplitude of 1 V and width of 20 ps (corresponding to a data rate of 50 Gbps) and rise and fall time of 8 ps. It shows that the single-bit responses of the Megtron 6 board experienced the least attenuations as predicted by glancing at the differential insertion loss shown. On the other hand, the single-bit responses for FR-4 suffered the larger attenuation and edge degradation closely followed by FR408HR when compared to the Megtron 6 boards. Although the single-bit response of the Nelco N4000-13 EPSI suffered similar attenuation and dispersion as FR408HR, it experienced the least delay due to its low dielectric constant.

Material for flexible PCB

What Substrate Material is used for Flexible PCBs?

Flexible PCBs are printed circuit boards that can be bent and twisted without breaking.

You find these PCBs useful in wearable technology especially in making biomedical equipment.

Consequently, the substrate material composition of these PCBs needs to accommodate bending and twisting forces.

Polyimide is the material commonly used for substrates in flexible PCBs.

It is furnished as a thin film with a narrow thickness range not exceeding 120micrometers.

You find that the thickness of the polyimide will determine its flexibility.

As such, a large thickness results in reduced flexibility or increased stiffness.

What are the Features of Polyimide PCB Material?

While polyimide is notable for its flexible property, it has other notable characteristics. They include:

Polyimide has a high working temperature range allowing its use in extreme military applications.

You find this material can withstand large thermal-induced strains.

Additionally, the electrical properties of polyimide are impressive.

Polyimide has remarkable tensile strength that gives it remarkable endurance in harsh application conditions.

Moreover, the ability to resist chemical interference by polyimides is high.

Some polyimides have a matching coefficient of expansion with copper allowing similar responses to thermal changes.

However, you find polyimides are limited in the following instances:

The rate of absorption of moisture and water content by polyimides is high.

Also, the absorbed moisture or water content can attribute to almost three percent of its weight.

You find polyimides are exorbitantly priced making them expensive.

While polyimides have exceptional temperature characteristics they are subject to the forces holding the layers together.

Material for Aluminium PCB

We can produce metal core PCB based on our stock material so you don’t have to wait long lead time on materials. We have a full range of top raw materials in stock to meet your metal core PCB application, such as BoYu, Ploytronics, Totking, Bergquist, Laird, Kinwong, Doosan, ITEQ, etc. we can also suggest local good quality metal core PCB based raw material manufacturer that fit your projects, and most important, it can reduce your cost .

Material for Microwave RF PCB

RO3000 datasheet

RO3000 laminates are ceramic filled PTFE composites intended for use in the commercial microwave and RF applications. R03000 series laminates are circuit materials with very consistent mechanical properties regardless of the dielectric constant selected. Due to this characteristic, when designing multi-layer boards with varying dielectric constants, there will be very little issues if any at all The dielectric constant VS temperature of RO3000 series materials is very stable. RO3000 laminates also are available in a wide range of dielectric constants (3.0 to 10.2). The most common applications are:

1. Surface mount RF components,

2. GPS antennas, and

3. Power amplifiers.

RO4000 datasheet

RO4000 laminates and pre-pregs possess favorable properties that are highly useful in microwave circuits and instances where controlled impedance is needed. This series of laminates are very price optimized and are also fabricated using standard FR4 processes which makes it suitable for multi-layer PCBs. Additionally, it can be processed lead-free. The series of RO4000 laminates offer a range of dielectric constants (2.55-6.15) and are available with UL 94 V-0 flame retardant versions. The most popular applications of this are:

1. RFID chips,

2. Power amplifiers,

3. Automotive radars, and

4. Sensors.

Material for Ceramic PCB

Ceramic PCB in high pressure, high insulation, high frequency, high temperature, and high reliable and minor volume electronic products, then Ceramic PCB will be your best choice.

Why Ceramic PCB has such excellent performance?

96% or 98% Alumina (Al2O3), Aluminum Nitride (ALN), or Beryllium Oxide (BeO)
Conductors material: For thin film technology, thick film technology, it’ll be silver palladium (AgPd), gold pllladium (AuPd); For DCB (Direct Copper Bonded) it’ll be copper only
Application temp: -55~850C
Thermal conductivity value: 16W~28W/m-K (Al2O3); 150W~240W/m-K for ALN , 220~250W/m-K for BeO;
Max compression strength: >7,000 N/cm2
Breakdown Voltage (KV/mm): 15/20/28 for 0.25mm/0.63mm/1.0mm respectively
Thermal expansion conefficient(ppm/K): 7.4 (under 50~200C)