The Design and Analysis of Rogers TMM 13I Microstrip Multilayer Transistor (TMM 13i) is a technical article that focuses on the performance of this new device. In this article, we will discuss some of the fundamental parameters of TMMs, including the Thermal Expansion Coefficient, Insertion Loss, and Dielectric constant. We also cover some of the key concepts related to the Microstrip design.
Coefficient of Thermal Expansion
The thermal conductivity of Rogers TMM laminates is more than twice that of conventional PTFE or ceramic laminates. You can bond them to brass or aluminum plates and cover with the electrodeposited copper foil. They are also available in bare copper and immersion tin. A wide range of application options makes Rogers TMM laminates an excellent choice for the fabrication of high-reliability plated through holes.
The CTE of TMM 13i microwave material is 15.15/15/23 in X, Y, and Z directions. This value is consistent with the thermal expansion coefficient of copper foil. In addition, the material’s isotropic dielectric constant (Dk) of 15/15/23 ensures the reliability and stability of microstrip lines. It can also help in microwave applications. TMM 13i microwave materials are available in both PTFE and ceramic substrate versions.
The high CTE and softness of PTFE laminates make them challenging to use in plated through-hole processing. To overcome these problems, we reinforce Rogers PTFE laminates with woven fiberglass. This helps solve issues related to softness and dimensional stability. As a result, Rogers TMM laminates are suitable for microstrip and strip-line applications and exhibit low dissipation.
The thermal conductivity of Rogers TMM microwave laminates is excellent. Its dissipation factor is 0.0019 – 0.0023 at 10 GHz. The thermal expansion coefficient of Rogers TMM 13i matches that of copper. This enables the high reliability and performance of microwave circuits. It also reduces consumption of energy and facilitates heat removal.
To ensure high-quality performance of Rogers materials, always ensure that the Dk and CTE of the substrates match. Different substrates have varying CTE, leading to functional failures and reliability concerns. In addition, the woven features of Rogers laminates must mesh tightly with one another to maximize their dielectric properties. This is important for the performance of PCBs when the high-frequency frequency is necessary.
Insertion Loss
PTFE and ceramic substrates are both popular for microwave applications. However, they both have significant insertion losses. The TMM 13i microwave material, with its isotropic dielectric constant, combines the advantages of both materials. Soft substrate processing also facilitates the design and fabrication process, making it an ideal choice for many applications. However, PTFE has a limited frequency range, and the TMM 13i is suitable for many applications.
This loss is a result of the roughness of the copper conductor. The degree of loss depends on the frequency of operation and the skin depth. Insertion loss is negligible at specific frequencies, while it can be significant at other frequencies. Insertion loss also becomes a thermal management issue, as it causes the PCB to warm up when RF power is applied. Despite this, low insertion loss can help maintain the digital pulse integrity.
The CuClad bonding film used by Rayming PCB & Assembly is a PTFE-based compound. Its maximum insertion loss is 8.4%, with minimal warpage. PTFE-based adhesives are typically suited for use in Rogers TMM 13i. But in some cases, the bonding film is not thick enough to prevent the adhesive from adhesion. Hence, a suitable bonding film is necessary to ensure a high level of signal integrity.
The highly controlled dielectric constant of Rogers laminates is also a significant consideration when choosing a substrate. It is just as crucial as the substrate thickness, which can be up to 3 GHz. Rogers also offers high-frequency laminates with greater control over the dielectric constant. They are also compatible with more sophisticated signal processing technologies. So, if you are looking for a high-frequency PCB, then it’s time to consider a high-frequency Rogers laminate.
Dielectric constant
The dielectric constant (Dk) of a particular microwave circuit board material is vital in determining its performance. The higher the Dk, the shorter the wavelength will be. However, a high Dk value doesn’t always equate to a higher frequency. Therefore, to ensure that you select the suitable dielectric constant, it is essential to understand the difference between dielectric constant (Dk) and tangent loss (TML) for microwave circuit boards.
Regarding thermal conductivity, Rogers TMM thermoset microwave materials have excellent values of between 0.70 and 0.76. They are twice as efficient as conventional PTFE laminates and ceramics. In addition, their high thermal conductivity allows for excellent heat removal and reduces energy consumption. The dielectric constant and low thermal expansion of Rogers TMM 13i materials perfectly match copper for excellent PTH reliability.
We can easily measure the difference between TMM 10i and TMM 13i materials by using the Dk of each material. For example, the Dk of a TMM 13i sheet is 9.80 in the x-direction, while that of a TMM 10i sheet is just over ninety-one. The difference between the two is quite remarkable and is a critical factor when comparing the dielectric constant values of different materials.
The CTE of Rogers TMM 13i is 15 to 26 ppm/degK, similar to the copper foil. That makes it an excellent choice for microwave circuits that need a range of thicknesses. However, if you are worried about the thickness of a TMM13i patch antenna, you can download the free PDF manual for your TMM13i microstrip line.
Microstrip technology
Thermosetting microwave PCB materials, such as Rogers TMM 13i, feature a consistent dielectric constant, a low thermal expansion coefficient, and excellent insulator performance. These materials are well-suited for microstrip and strip-line applications and have outstanding electrical and mechanical properties. These laminates are a cost-effective alternative to traditional copper-clad insulators.
The TMM 13i has an exceptionally low thermal coefficient of expansion (CTE), resulting in high-reliability plated through holes. It also has a thermal expansion coefficient that is nearly equivalent to copper, allowing for wire bonding without pad lifting. Moreover, the TMM 13i material is available in various colors and materials, including bare copper and immersion tin.
Because microvias require laser drilling, the price of Rogers substrates can increase by five to 10 percent. In addition, custom-made Rogers laminates have extra costs due to their uniqueness. These designs typically require special tools and equipment. In addition, the process can be time-consuming, and buried vias can add 20 percent to the overall substrate price. While it may seem a hassle to splice multiple layers of copper on one substrate, the advantages of microstrip PCBs are many.
Microstrip circuits have many advantages, and TMM materials are especially versatile. For example, the TMM 13i material has an excellent dielectric constant. This is a critical attribute when using this type of technology in high-frequency circuits. It also allows a wide range of temperatures and moisture content. As a result, it is particularly compatible for use in high-frequency applications. For this reason, it is an ideal material for microstrip circuits.
Surface plating
Using Rogers TMM as the surface plating material can produce high-quality microwave elements. We bond these laminates to brass or aluminum plates with an electrodeposited copper film. This coating is available in TMM 3, TMM 4, and TMM 10 varieties. To learn more, read on! Below are some benefits of this surface plating process. Here is a closer look at the advantages of TMM.
Producing these materials is similar to FR-4 laminate, with minor differences in lamination parameters. Rogers laminates are often essential for digital and RF applications and microwave frequencies. The surface plating process may require an edge-coupled sequence of conductors or a PCB conductor pattern. This process also allows for a band-pass filter. For this reason, this type of surface plating is ideal for RF, microwave, and digital circuit boards.
The TMM laminates are extremely flexible and have a low thermal coefficient. As a result, they do not soften under high temperatures, making wire bonding a snap. Another advantage of Rogers TMM materials is their isotropic coefficient of thermal expansion. Compared to other materials, they are resistant to etching shrinkage and high loss. The TMM material is also available with woven fiberglass reinforcement.
Surface plating of Rogers TMM 13I may also require the addition of microvias, which require a laser drilling process. This adds five to ten percent to the total price of the substrate. This process is necessary because the current PCB designs require very tiny components. These tiny components need a small space between conductive copper elements. By leaving sufficient space, it helps keep the PCB substrate costs low.
