A Practical Method for Trace Exposure and Roughness Measurements and Implementation in High Speed Package Design

Author(s):  
Valentina Korchnoy ◽  
Jacov Brener

Abstract High frequency signal propagation through transmission lines has been an important discipline for RF engineers. With advancements in digital technologies, especially when data rates reached multiple Gb/s, package designers have to consider parameters such as transmission loss and trace impedance in order to maintain signal integrity. For high frequency signals, the surface roughness of the copper trace becomes increasingly significant in determining conduction loss, due to current confinement to the conductor surface by the skin effect. Accurate 3D conductor surface maps are required for correct trace insertion loss simulation. Practical methods for package trace exposure and 3D surface height map acquisition are discussed in this paper. Advantages and disadvantages of these methods, and their implementation to real packages are shown. Using electrical parameters resulting from a 3D trace surface map, the error between electrical simulations and actual measurements of insertion loss in an FCBGA package have been reduced from 6% to nearly zero, enabling tighter margins in 10GB/s high speed serial design.

2013 ◽  
Vol 2013 (CICMT) ◽  
pp. 000047-000053
Author(s):  
J. Phillip Bailey ◽  
Michael D. Glover ◽  
Emmanuel Decrossas ◽  
Kaoru Porter ◽  
Tom Cannon ◽  
...  

The many advantages of low temperature co-fired ceramic (LTCC) materials are increasing their use in multi-layer systems containing multiple high-frequency / high-speed digital interconnects. Although construction of such interconnects is possible with current fabrication techniques, the loss exhibited by transmission lines at high frequencies limits their application by increasing system power consumption or requiring complex transceivers. Use of non-standard metal printing processes provides one possibility for realizing lower insertion loss desired for these interconnects. We have fabricated and evaluated representative single-ended and differential stripline transmission line structures using single, double, and mirror printing techniques for Ag metalization in DuPont 9K7 LTCC, to explore their suitability for high-frequency/high-speed applications. Discussion of analysis performed on cross-sections of these structures to determine post-firing geometry, as well as the level of fabrication control afforded over these parameters will be presented. To predict their performance for high-speed interconnects, 3D electromagnetic (3DEM) simulation models for characterizing the frequency performance of single-ended and differential structures have been also been developed. These 3DEM models have also been used in time domain simulations to verify digital signal capability by demonstrating structure performance at data rates exceeding 25 Gbps. Measurements of fabricated structures corresponding to the 3DEM models have also been performed in both the time and frequency domain and will be compared to the simulation results to confirm 3DEM model accuracy. The culmination of results from simulation and measurement will be used to present the differences, advantages, and disadvantages of each fabrication technique.


2012 ◽  
Vol 2012 (1) ◽  
pp. 000239-000243
Author(s):  
Srinidhi Raghavan Narasimhan ◽  
A. Ege Engin

The 3D IC integration technology and silicon interposers rely on through silicon vias (TSVs) for vertical interconnections. Hence, the medium carrying high frequency signals is lossy silicon (Si). Fundamental understanding of wave propagation through TSVs is essential for successful implementation of 3D IC integration technology as well as for the development of Si interposers at RF/microwave frequencies. The focus of this paper is characterization and modelling of TSVs and Si to explore high speed signal propagation through the lossy Si medium. To understand better the physical significance of the TSV, we will establish a framework for wave propagation through TSVs based on dielectric quasi-TEM, skin effect, and slow-wave modes similar to MIS micro-strip lines. For validation of the existence of these modes, full wave simulation results will be compared with simpler two dimensional transmission line simulators.


2018 ◽  
Vol 2018 (1) ◽  
pp. 000415-000418 ◽  
Author(s):  
Shinichiro Abe ◽  
Kazuyuki Mitsukura ◽  
Yuki Imazu ◽  
Masaya Toba ◽  
Takashi Masuko ◽  
...  

Abstract The interposer or fan-out packaging technology with ultra-fine line/space and high frequency signal has been required in order to achieve high speed interconnection between chips with low cost. In this paper, we have newly developed low Dk and Df photosensitive insulation material. The additional features of the developed materials are very low moisture absorptivity less than 0.3 wt%, low anion impurities and high resistance to hydrolysis. The micro-strip line was fabricated to evaluate the influence of developed material. The insertion loss from transmission lines on Material C shows much lower loss than the conventional reference material at higher frequencies. The peel strength to the sputtered Ti and Cu is over 0.7 kN/m. The material also demonstrated SAP fabrication compatibility with fine circuitry and passed insulation reliability by biased-HAST showing no copper migration measured by EDX.


2013 ◽  
Vol 753-755 ◽  
pp. 1405-1408
Author(s):  
Hua Cai Lu ◽  
Xuan Yu Yao ◽  
Juan Ti

This paper describes a composite sensorless position and speed detection algorithm designed for permanent magnet linear synchronous motor (PMLSM). A high-frequency voltage signal injection method is used at starting and low speed, and a back-EMF integrate method is used at high speed, and the two kinds of method are fused by weighting method in the transition speed area. Simulation results show that estimation accuracy of this composite estimation method is satisfactory, and the sensorless control system based on this method has good dynamic response characteristics within full speed.


2014 ◽  
Vol 1006-1007 ◽  
pp. 639-642
Author(s):  
Chun Fu Li ◽  
Yan Qin Li

The purpose of the solenoid current control is to decrease holding current of the solenoid by selecting suitable frequency and duty, to keep the solenoid opening reliably for a long time and reduce power consumption and improve the solenoid close feature. In this paper, the high frequency signal in oil pressure holding process is determined by theoretical analysis and experimental study. The purpose of the study is to determine the ideal current in the working process of the solenoid.


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