DDR4 BER Degradation Due to Crack in FBGA Package Solder Ball

This paper measures bit error rate degradation in DDR4 due to crack in fine pitch ball grid array (FBGA) package solder ball. Thermal coefficient mismatch between the package and printed circuit board material causes cracks to occur in solder balls. These cracks change the electrical model of the solder ball and introduce parallel capacitance in the electrical model. The capacitance causes higher frequency attenuation and closes the data eye. As the data rate of the DDR4 increases there are more data eye closures. The data eye closure causes bit error rate (BER) degradation as the timing margin and voltage margin decreases. This degradation reduces the reliability of the system and causes more intermittent errors. DDR4 data line is loaded with a parallel capacitive element to mimic a crack in solder ball. The measured data eye shows a decrease in eye width. Bathtub plots are created for comparison of cracked solder ball and intact solder ball. The bathtub plots show the BER degradation due to crack in solder ball.

Areal Surface Texture Parameters for Copper/Glass Plating Adhesion Characteristics

Glass as an alternative printed circuit board material and interposer has been investigated for use in the micro-electronics industry. Electroless copper plating is used to provide the conductive layer, but there is limited understanding of how the surface topography of the glass substrate affects the copper/glass bonding strength exhibited in the current literature. A laser ablation technique was used to prepare glass surfaces with micro-scale structured features in this study, and these features were characterized quantitatively using areal surface texture parameters. The copper/glass bonding adhesion strength was quantified using a scratch testing technique, and the relationships between the critical loads measured and the areal surface parameters, as well as discussion of the underlying mechanisms, are presented in this report. Statistical analysis was employed to identify the most relevant areal parameters that may be used for prediction of the copper/glass bonding strength and for design of adhesion promoting surface textures. The experimental results suggest that the most significant areal surface texture parameters to consider are Sq, Sdq, Sdr, Sxp, Vv, Vmc, and Vvc, and the recommended value range for each parameter for optimal plating adhesion performance is given.

Change Management

This report is prepared for preparing the change for new product of the board manufacturing company. The Change from the external market force of market demand on the supply of thin sheet board material thus prompted the Marketing department to make the market survey that there is a need to introduce a new product to be competitive in the board manufacturing market and offer a complete range of board products for the building industry. Internally, The Marketing Department has to convince the top management and the main stakeholder to agree and accept the urgent change. At the same time has to balance the sales revenue with the cost of technology investment and economical scale perspectives of producing the targeted product. The proposal of this change’s success should be judged by how the new product can help to sustain the future growth of the company and give a reasonable revenue. Currently, the company produces Building Board material of size 1220 mm x 2440 mm and thickness ranging from 10mm, 12mm, 16mm, and 18mm. The Marketing Department wants to reduce the thickness to 4mm and 6mm and the size change to 1220 mm x 1220 mm and 1220 mm x 610 mm. For this request, The Marketing Department has to show the stakeholder and Top Management the purpose of the change and convince the Top Management, stakeholder (include the factory team ) to accept the Change. Strong support from top management and stakeholder is very important. Marketing Department has to show the market size of the thin board and projected the sale volume. The comparison of the sale revenue-again the investment sum has to be competitive with short break-even point so that the figure of dollars and cents provides strong persuasive power and support for the stakeholder and top management to strongly consider and accept the investment and the change.

Research on Existing Problems and Improvement Measures of Fabricated Composite Wallboard

In recent years, fabricated composite wall panels have been widely used in building materials markets at home and abroad, and their main advantages are convenient construction, low energy consumption, and heat and sound insulation. However, fabricated composite wall panels also have some common problems in practical applications, such as large dead weight, weak seismic performance, prone to cracks, and failing to meet the higher energy-saving requirements of thermal insulation external walls. This article analyzes the board material and overall structure of the fabricated composite wallboard, proposes corresponding solutions to make up for its weakness in some performance, and gives the specific construction process and accuracy requirements.

Analisis Kebisingan Kawasan Permukiman di Sepanjang Frontage Road A. Yani Surabaya

Surabaya city is one of the cities in Indonesia which has the most advanced development in various fields, such as economy, education and transportation. Rapid city development has positive and negative impacts. Positive impact such as high technology from various infrastructures for transportation, health, education, entertainment and others that support the daily activities of Surabaya people. The negative impact is the declining quality of the environment, which can cause health problems and community discomfort. The research method uses quantitative descriptive methods. This study analyzes the noise caused by traffic that occurs in residential areas along the frontage road A.Yani Surabaya (Menanggal I, Jemur Gayungan I and Jemur Wonosari Masjid Alley). Noise level values was measured using sound level meter and analyzed using a statistical formula. The results showed the value of the noise level in daytime activity (LS) in Menanggal I settlement was 79.96 dB (A), Jemur Gayungan I settlement was 80.28 dB (A) and Jemur Wonosari Mosque mosque settlement was 78.44 dB ( A), and have exceeded the quality standard. Noise control can be done with vegetation barriers at noise sources, settlements and along the frontage road. Reduction of noise level can be done by replacement of wall materials with glass or a combination of glass and brick, as well as a combination design in the interior of the room by adding gypsum board material to the ceiling and room dividers.

Applicability of Different Bio-based Polymers for Wiring Boards

The paper gives a review of experiments for the application of biodegradable, sustainable polymers as a wiring board material. In the paper two different biobased materials and the standard PCB materials FR4 and FR2 were compared. The investigations refer to mechanical, electrical performance, surface quality the flammability and applicability for Polymer Thick Film Technology (PTFT) of the biobased material. The biobased materials are polylactic acid (PLA) mixed with different contents of cellulose acetate (CA) or flame retardant zinc pyrophosphate (ZnPP) and polyurethane (PU) with CA. The results show that the addition of CA to the polymers leads to a change of different properties for PLA and to a significant change in mechanical properties for PU. The use of ZnPP in PLA shows major improvements regarding the flammability of the polymer. The properties of the samples are in the same order of magnitude as the properties of FR2.