Understanding the Effects of Process Parameters to Compensate for Substrate Warpage in Chip on Flex (CoF) Assembly Using Conventional Reflow

2019 ◽  
Vol 2019 (1) ◽  
pp. 000428-000433
Author(s):  
Varun Soman ◽  
Vikram Venkatadri ◽  
Mark D. Poliks
Keyword(s):  
Substrate Surface ◽  
Cost Effective ◽  
High Volume ◽  
High Yield ◽  
Solder Paste ◽  
Conductive Adhesives ◽  
Process Yield ◽  
Aperture Diameter ◽  
Solder Balls ◽  
Aperture Opening

Abstract Mounting rigid silicon (Si) die on a flex substrate presents a unique set of challenges. Substrate surface flatness and warpage of the flex substrate before and during thermal processing being two of the biggest issues. Various processes such as thermocompression bonding using anisotropic conductive films and thermosonic bonding using non-conductive adhesives have been shown to be effective for chip on flex (CoF) applications. However, these processes sacrifice process throughput and are less cost effective. Hence these methods may not be suitable for high volume manufacturing (HVM). For this reason, a process that is suitable for HVM and uses standard reflow processes and equipment is highly desirable. This works presents preliminary results for such a CoF process that uses a simple fixture and standard processes, materials and equipment. CoF process for Si die using two types of interconnects, solder balls or Cu pillars, was developed. Solder paste was stencil printed before pick and place of the Si die to offset the lack of flex substrate flatness and substrate warpage. The effect of stencil aperture diameter and placement force on process yield and stand-off height was studied. It was demonstrated that high yield can be obtained with a process that uses wider stencil aperture opening for both type of interconnects investigated. It was also observed that the placement force did not have any effect on process yield or stand-off height. The process can also be easily scaled up for HVM.

Precision Jetting of Solder Paste – A Versatile Tool for Small Volume Production

2014 ◽  
Vol 2014 (1) ◽  
pp. 000438-000443 ◽  
Author(s):  
K.-F. Becker ◽  
M. Koch ◽  
S. Voges ◽  
T. Thomas ◽  
M. Fliess ◽  
...  
Keyword(s):  
Process Development ◽  
Droplet Diameter ◽  
Rheological Behaviour ◽  
High Volume ◽  
Electronic System ◽  
High Viscosity ◽  
Solder Paste ◽  
Process Data ◽  
Current Standard ◽  
Conductive Adhesives

During the last years, jetting processes for higher viscosity materials have gained widespread interest in microelectronics manufacturing. Main reasons for this interest are high throughput/productivity of jetting, contactless material deposition, high volume precision and freely designable deposition patterns. In previous studies [i,ii] we have demonstrated the jetability of different resin-based materials, being exemplary for unfilled adhesive, for low viscous Underfill resin and for higher viscosity Glob Top materials. The focus of our previous work was on the dosing of various encapsulants - Underfill material with low viscosity and near Newtonian behaviour and Glob Top resins, being non-Newtonian fluids due to higher matrix viscosity and higher filler content (up to 70 wt %) with resulting increased filer/filler and filler/matrix interaction. During the last years jetting has become widely used and has been applied to the dosing of much more complex materials, combining high viscosity matrix materials with odd shaped and compressive particles. Examples for these materials are conductive adhesives and also solder pastes, where the jetting system developed by Swedish company Mydata set's the current standard for solder paste jetting. In a technological study solder paste jetting using different jetting systems has been investigated in comparison to solder paste dispensing and solder paste printing, especially material rheological behaviour and the correspondence to processability have been evaluated in detail. To illustrate the potential of solder paste jetting as a flexible and powerful tool for electronic system prototyping, a test vehicle has been designed, containing areas for SMD soldering and for process reproducibility. To determine process quality not only basic process data on droplet diameter, resulting material depot size and positioning accuracy have been evaluated, but also statistical means have been employed to determine process homogeneity and stability depending on the respective parameter set. Summarized this paper gives an insight into solder jet process development and describes material rheology demands and limitations and thus allows the optimized use of advanced solder jetting technology for electronics assemblies.

Manufacturing Readiness of BVA(TM) Technology for Fine-Pitch Package-on-Package

2014 ◽  
Vol 2014 (DPC) ◽  
pp. 000930-000959
Author(s):  
Wael Zohni ◽  
Rajesh Katkar ◽  
Rey Co ◽  
Rizza Cizek
Keyword(s):  
High Performance ◽  
Cost Effective ◽  
High Volume ◽  
Third Party ◽  
High Yield ◽  
Test Vehicle ◽  
Industry Standard ◽  
Fine Pitch ◽  
High Bandwidth ◽  
Manufacturing Readiness

Package-on-Package (PoP) has become common for packaging the processor and memory subunit in today's smartphones and tablets. Today's PoPs provide only about 300 interconnects between the base and top packages due to physical limitations posed by existing manufacturing methods. As a result, memory data bandwidth is limited to 25.6 GB/s at 1600 MHz DDR signal speeds. With a trend towards System-on-Chip (SoC) mobile processors with multi-core CPU, memory bandwidth requirements are sharply increasing. To meet these needs, a wide IO memory industry standard has emerged to specify 512 memory data interconnects. This standard provides about 4 times current bandwidths (>100 GB/s) even at lower 800 MHz DDR signal speeds. For memory devices to offer 512 data lines, a total of about 1000 interconnects are needed to include the accompanying address, control, power and ground signals required for operation. No current PoP technology can offer 1000 interconnects, due to limited fine-pitch capability within the standard 14mm x 14mm package outline. Although industry expectation is for Through-Silicon-Via (TSV) technology to eventually offer a high-bandwidth solution, TSV manufacturing is still being developed and not expected to be widely available for a number of years. A new high-performance PoP interconnect technology called Bond-Via-Array (BVA [TM]) has been developed to provide high-bandwidth interconnect capability today. A BVA test vehicle package demonstrating 1020 processor to memory interconnects at 0.24mm pitch has been assembled inside the industry-standard 14mm x 14mm package outline. These fine pitch vertical interconnects are achieved utilizing well established wirebond equipment and process. As a result, BVA provides a cost-effective and reliable path to high-performance PoP. This paper details equipment and process developments related to high-volume-manufacturing (HVM) readiness of BVA technology. In addition to assembly process and equipment, test hardware that can accommodate fine pitch wire-tip interconnects needs to be demonstrated for manufacturing readiness. Socket and test hardware development and verification studies utilizing the latest 0.24mm pitch test vehicle are underway in cooperation with a 3rd party test hardware supplier. Goals include demonstrating feasibility of the fine-pitch PoP test approach as well as establishing sources for such hardware. In summary, BVA PoP technology enables 1000+ interconnects in a standard PoP outline while taking advantage of existing materials and infrastructure. To ensure manufacturing readiness, package assembly and test demonstrations are being carried out with third party vendors. Results indicate that with proper design and process optimization, high yield assembly and test is possible, and this technology is ready for high volume manufacturing.

Quality Improvement of the DNA extracted by boiling method in Gram negative bacteria

2017 ◽  
Vol 6 (04) ◽  
pp. 5347 ◽  
Author(s):  
Omar B. Ahmed* ◽  
Anas S. Dablool
Keyword(s):  
Dna Extraction ◽  
Control Method ◽  
Extraction Procedure ◽  
Cost Effective ◽  
High Yield ◽  
Gram Negative Bacteria ◽  
Bacterial Dna ◽  
Gram Negative ◽  
E Coli

Several methods of Deoxyribonucleic acid (DNA) extraction have been applied to extract bacterial DNA. The amount and the quality of the DNA obtained for each one of those methods are variable. The study aimed to evaluate bacterial DNA extraction using conventional boiling method followed by alcohol precipitation. DNA extraction from Gram negative bacilli was extracted and precipitated using boiling method with further precipitation by ethanol. The extraction procedure performed using the boiling method resulted in high DNA yields for both E. coli and K. pneumoniae bacteria in (199.7 and 285.7μg/ml, respectively) which was close to control method (229.3 and 440.3μg/ml). It was concluded that after alcohol precipitation boiling procedure was easy, cost-effective, and applicable for high-yield quality of DNA in Gram-negative bacteria.

scholarly journals Cost Effectiveness of Transbronchial Needle Aspiration

1999 ◽  
Vol 6 (4) ◽  
pp. 332-335 ◽  
Author(s):  
Jennifer A Crocket ◽  
Eric YL Wong ◽  
Dale C Lien ◽  
Khanh Gia Nguyen ◽  
Michelle R Chaput ◽  
...  
Keyword(s):  
Cost Effectiveness ◽  
Cost Effective ◽  
Diagnostic Procedures ◽  
Needle Aspiration ◽  
Benign Disease ◽  
University Hospital ◽  
High Yield ◽  
Transbronchial Needle Aspiration ◽  
Computed Tomographic ◽  
The Cost

OBJECTIVE: To evaluate the yield and cost effectiveness of transbronchial needle aspiration (TBNA) in the assessment of mediastinal and/or hilar lymphadenopathy.DESIGN: Retrospective study.SETTING: A university hospital.POPULATION STUDIED: Ninety-six patients referred for bronchoscopy with computed tomographic evidence of significant mediastinal or hilar adenopathy.RESULTS: Ninety-nine patient records were reviewed. Three patients had two separate bronchoscopy procedures. TBNA was positive in 42 patients (44%) and negative in 54 patients. Of the 42 patients with a positive aspirate, 40 had malignant cytology and two had cells consistent with benign disease. The positive TBNA result altered management in 22 of 40 patients with malignant disease and one of two patients with benign disease, thereby avoiding further diagnostic procedures. The cost of these subsequent procedures was estimated at $27,335. No complications related to TBNA were documented.CONCLUSIONS: TBNA is a high-yield, safe and cost effective procedure for the diagnosis and staging of bronchogenic cancer.

Cost-effective, high-volume molecular beam epitaxy using a multi 6-in wafer reactor

2001 ◽  
Vol 227-228 ◽  
pp. 143-149
Author(s):  
Larry Leung ◽  
Damian Davison ◽  
Arthur Cornfeld ◽  
Frederick Towner ◽  
Dave Hartzell
Keyword(s):  
Molecular Beam Epitaxy ◽  
Molecular Beam ◽  
Cost Effective ◽  
High Volume

Application of Epoxy Resin for Improvement of the Banana Stem-Acoustic Panel

2021 ◽  
Vol 15 ◽  
Author(s):  
Mohd Azril Riduan ◽  
Mohd Jumain Jalil ◽  
Intan Suhada Azmi ◽  
Afifudin Habulat ◽  
Danial Nuruddin Azlan Raofuddin ◽  
...  
Keyword(s):  
Oleic Acid ◽  
Kinetic Modelling ◽  
Low Cost ◽  
Cost Effective ◽  
Performic Acid ◽  
High Yield ◽  
Renewable Materials ◽  
Runge Kutta Method ◽  
To Come

Background: Greener epoxidation by using vegetable oil to create an eco-friendly epoxide is being studied because it is a more cost-effective and environmentally friendly commodity that is safer than non-renewable materials. The aim of this research is to come up with low-cost solutions for banana trunk acoustic panels with kinetic modelling of epoxy-based palm oil. Method: In this study, the epoxidation of palm oleic acid was carried out by in situ performic acid to produce epoxidized palm oleic acid. Results: Banana trunk acoustic panel was successfully innovated based on the performance when the epoxy was applied. Lastly, a mathematical model was developed by using the numerical integration of the 4th order Runge-Kutta method, and the results showed that there is a good agreement between the simulation and experimental data, which validates the kinetic model. Conclusion: Overall, the peracid mechanism was effective in producing a high yield of epoxy from palm oleic acid that is useful for the improvement of acoustic panels based on the banana trunk.

scholarly journals An Efficient and Improved Methodology for the Screening of Industrially Valuable Xylano-Pectino-Cellulolytic Microbes

2015 ◽  
Vol 2015 ◽  
pp. 1-7 ◽  
Author(s):  
Avtar Singh ◽  
Amanjot Kaur ◽  
Anita Dua ◽  
Ritu Mahajan
Keyword(s):  
Low Cost ◽  
Cost Effective ◽  
Industrial Sector ◽  
Agricultural Residues ◽  
High Yield ◽  
Cellulolytic Enzymes ◽  
Cellulolytic Activity ◽  
Nutrient Media ◽  
First Report ◽  
Primary Screening

Xylano-pectino-cellulolytic enzymes are valuable enzymes of the industrial sector. In our earlier study, we have reported a novel and cost effective methodology for the qualitative screening of cellulase-free xylano-pectinolytic microorganisms by replacing the commercial, highly expensive substrates with agricultural residues, but the microorganisms with xylanolytic, pectinolytic, cellulolytic, xylano-pectinolytic, xylano-cellulolytic, pectino-cellulolytic, and xylano-pectino-cellulolytic potential were obtained. The probability of getting the desired combination was low, so efforts were made to further improve this cost effective methodology for obtaining the high yield of the microbes capable of producing desired combination of enzymes. By inclusion of multiple enrichment steps in sequence, using only practically low cost substrates and without any nutrient media till primary screening stage, this improved novel protocol for screening gave only the desired microorganisms with xylano-pectino-cellulolytic activity. Using this rapid, efficient, cost effective, and improved methodology, microbes with required combination of enzymes can be obtained and the probability of getting the desired microorganisms is cent percent. This is the first report presenting the methodology for the isolation of xylano-pectino-cellulolytic positive microorganisms at low cost and consuming less time.

scholarly journals A Roadmap towards Successful Nanocapsule Synthesis via Vesicle Templated RAFT-Based Emulsion Polymerization

Polymers ◽  
2018 ◽  
Vol 10 (7) ◽  
pp. 774 ◽  
Author(s):  
Wendy Rusli ◽  
Alexander Jackson ◽  
Alexander van Herk
Keyword(s):  
Emulsion Polymerization ◽  
Special Form ◽  
Chain Transfer ◽  
Cost Effective ◽  
Solid Particles ◽  
High Yield ◽  
Full Understanding ◽  
High Demand ◽  
Molecular Control ◽  
Reversible Addition

Vesicle templated emulsion polymerization is a special form of emulsion polymerization where the polymer is grown from the outside of the vesicle, leading to nanocapsules. Cost effective nanocapsules synthesis is in high demand due to phasing out of older methods for capsule synthesis. Although the first indications of this route being successful were published some 10 years ago, until now a thorough understanding of the parameters controlling the morphologies resulting from the template emulsion polymerization was lacking. Most often a mixture of different morphologies was obtained, ranging from solid particles to pro-trusion structures to nanocapsules. A high yield of nanocapsules was not achieved until now. In this paper, the influence of initial vesicle dispersion, choice of the Reversible Addition-Fragmentation chain Transfer (RAFT) species and oligomer, monomer and crosslinker have been investigated. It turns out that good initial vesicle dispersion, molecular control of the RAFT process, a not too hydrophobic monomer and some crosslinking is needed to result in high yield of nanocapsules. In previous work, the level of RAFT control was often suboptimal and not properly verified and although nanocapsules were shown, other morphologies were also present. We now believe we have a full understanding of vesicle templated nanocapsules synthesis, relevant to many applications.

scholarly journals The role of positively charge poly-L-lysine in the formation of high yield gold nanoplates on the surface for plasmonic sensing application

PLoS ONE ◽  
2021 ◽  
Vol 16 (11) ◽  
pp. e0259730
Author(s):  
Marlia Morsin ◽  
Suratun Nafisah ◽  
Rahmat Sanudin ◽  
Nur Liyana Razali ◽  
Farhanahani Mahmud ◽  
...  
Keyword(s):  
Substrate Surface ◽  
Surrounding Medium ◽  
Resonance Effect ◽  
Maximum Yield ◽  
Single Layer ◽  
Localized Surface Plasmon ◽  
High Yield ◽  
Synthesis Process ◽  
Wavelength Shift ◽  
Plasmonic Sensor

An anisotropic structure, gold (Au) nanoplates was synthesized using a two-step wet chemical seed mediated growth method (SMGM) directly on the substrate surface. Prior to the synthesis process, poly-l-lysine (PLL) as a cation polymer was used to enhance the yield of grown Au nanoplates. The electrostatic interaction of positive charged by PLL with negative charges from citrate-capped gold nanoseeds contributes to the yield increment. The percentage of PLL was varied from 0% to 10% to study the morphology of Au nanoplates in term of shape, size and surface density. 5% PLL with single layer treatment produce a variety of plate shapes such as hexagonal, flat rod and triangular obtained over the whole substrate surface with the estimated maximum yield up to ca. 48%. The high yield of Au nanoplates exhibit dual plasmonic peaks response that are associated with transverse and longitudinal localized surface plasmon resonance (TSPR and LSPR). Then, the PLL treatment process was repeated twice resulting the increment of Au nanoplates products to ca. 60%. The thin film Au nanoplates was further used as sensing materials in plasmonic sensor for detection of boric acid. The anisotropic Au nanoplates have four sensing parameters being monitored when the medium changes, which are peak position (wavelength shift), intensity of TSPR and LSPR, and the changes on sensing responses. The sensor responses are based on the interaction of light with dielectric properties from surrounding medium. The resonance effect produces by a collection of electron vibration on the Au nanoparticles surface after hit by light are captured as the responses. As a conclusion, it was found that the PLL treatment is capable to promote high yield of Au nanoplates. Moreover, the high yield of the Au nanoplates is an indication as excellent candidate for sensing material in plasmonic sensor.

Sign in / Sign up

Export Citation Format

Share Document