Technical Library | 2019-06-04 10:19:46.0
Interconnection technology relies very heavily on the ability of the conductors on a printed wiring assembly to maintain reliable signal integrity. Harsh environmental factors can precipitate a loss of conductivity due to oxidation and corrosion. Connections are typically soldered or inserted using pressure fitted connectors to obtain enough surface contact to meet the electrical conductivity requirements. In pressure contacts, surface integrity is especially critical where the abrasive effects of retraction and insertion can wear off the metallic finish from the contact area. This can expose the underlying copper or nickel and lead to increased resistance at the contact points. These types of conductors are frequently found in card edge connectors where the terminations are plated with a layer of nickel and gold (frequently referred to as gold fingers). A hard gold is typically used containing very small amounts of nickel and cobalt to increase the wear resistance.
Technical Library | 2011-05-12 19:04:05.0
We clarify the role of signal loss measurements, aka Total Loss, in specifying and qualifying circuit board materials for high-speed electronic design. We then demonstrate the NIST Multiline measurement technique in particular by characterizing test line
Technical Library | 2015-04-30 20:17:03.0
Higher-speed signal transmission is increasingly required on a printed circuit board to handle massive data in electronic systems. So, signal transmission loss of copper wiring on a printed circuit board has been studied. First, total signal loss was divided into dielectric loss and conductor loss quantitatively based on electromagnetic theory. In particular, the scattering loss due to surface roughness of copper foil has been examined in detail. And the usefulness of the copper foil with low surface roughness has been demonstrated.
Technical Library | 2021-07-06 21:24:59.0
The amount of information transferred on wireless networks has increased dramatically with the tremendous growth of mobile phones, Internet access, and hand held devices. In order to build the infrastructure needed to handle ever increasing data transfer, manufacturers of electronic devices turn to high speed, high frequency electronic signals. The need to render these electronic devices portable is another technology driver. The merge of high-frequency signals with small geometry conductive traces means that the topic of signal loss has reached a critical point in existing device production.
Technical Library | 2014-02-13 16:46:23.0
The high speed transmission applications in the electronic product become inevitable developing trend. The signal integrity becomes the most important issue in the electronics industry. The material suppliers, PCB manufacturers, OEM designers commonly face the serious issue "how to keep signal integrity operated in the high speed transmission" for the modern electronic application nowadays
Technical Library | 2016-03-24 17:37:09.0
Today's Electronic Industry is changing at a high pace. The root causes are manifold. So world population is growing up to eight billions and gives new challenges in terms of urbanization, mobility and connectivity. Consequently, there will raise up a lot of new business models for the electronic industry. Connectivity will take a large influence on our lives. Concepts like Industry 4.0, internet of things, M2M communication, smart homes or communication in or to cars are growing up. All these applications are based on the same demanding requirement – a high amount of data and increased data transfer rate. These arguments bring up large challenges to the Printed Circuit Board (PCB) design and manufacturing.This paper investigates the impact of different PCB manufacturing technologies and their relation to their high frequency behavior. In the course of the paper a brief overview of PCB manufacturing capabilities is be presented. Moreover, signal losses in terms of frequency, design, manufacturing processes, and substrate materials are investigated. The aim of this paper is, to develop a concept to use materials in combination with optimized PCB manufacturing processes, which allows a significant reduction of losses and increased signal quality.
Technical Library | 2019-02-13 13:45:11.0
Development of information and telecommunications network is outstanding in recent years, and it is required for the related equipment such as communication base stations, servers and routers, to process huge amount of data in no time. As an electrical signal becomes faster and faster, how to prevent signal delay by transmission loss is a big issue for Printed Circuit Boards (PCB) loaded on such equipments. There are two main factors as the cause of transmission loss; dielectric loss and conductor loss. To decrease the dielectric loss, materials having low dielectric constant and low loss tangent have been developed. On the other hand, reducing the surface roughness of the copper foil itself to be used or minimizing the surface roughness by modifying surface treatment process of the conductor patterns before lamination is considered to be effective in order to decrease the conductor loss. However, there is a possibility that reduction in the surface roughness of the conductor patterns will lead to the decrease in adhesion of conductor patterns to dielectric resin and result in the deterioration of reliability of PCB itself. In this paper, we will show the evaluation results of adhesion performance and electrical properties using certain type of dielectric material for high frequency PCB, several types of copper foil and several surface treatment processes of the conductor patterns. Moreover, we will indicate a technique from the aspect of surface treatment process in order to ensure reliability and, at the same time, to prevent signal delay at the signal frequency over 20 GHz.
Technical Library | 2012-06-27 18:26:34.0
First published in the 2012 IPC APEX EXPO technical conference proceedings. Signal integrity analysis has shown that printed circuit board (PCB) insertion loss is a key factor affecting high speed channel performance. Determining and controlling PCB inser
Technical Library | 2008-02-26 15:02:19.0
More and more chip packages need multi-GHz RF structures to meet their performance targets. The ideal chip package needs to combine RF features with Digital features for these applications. They drive low-loss, controlled impedance transmission lines, flexibility in assigned signal and power layers, and clearances of various shapes in power layers. Building these features in a chip package is difficult without making the stack-up very thick or compromising the reliability of the product. In the present paper, we have designed and built a flip-chip package test vehicle (TV) to make new RF structures, using Z-axis interconnection (Zinterconnect) building blocks.
Technical Library | 2018-04-18 23:55:01.0
Higher functionality, higher performance and higher reliability with smaller real estate are the mantras of any electronic device and the future guarantees more of the same. In order to achieve the requirements of these devices, designs must incorporate fine line and via pitch while maintain good circuitry adhesion at a smooth plating-resin interface to improve signal integrity. The Semi-Additive Process (SAP) is a production-proven method used on low dielectric loss tangent (Df) build-up materials that enables the manufacture of ultra-fine circuitry. (...) This paper will discuss a new SAP process for low loss build-up materials with low desmear roughness (Ra= 40-100 nm) and excellent adhesion (610-680 gf/cm) at various processing conditions. Along with the process flow, the current work will also present results and a discussion regarding characterization on the morphology and composition of resin and/or metal plating surfaces using scanning electron microscopy (SEM) and energy dispersive X-ray spectroscopy (EDX), surface roughness analysis, plating-resin adhesion evaluation from 90o peel tests
