scholarly journals Critical Insights in the Application of Convection and Pressure Curing in Eliminating DAF Voids

2020 ◽  
pp. 36-42
Author(s):  
Bryan Christian S. Bacquian ◽  
Rennier Rodriguez ◽  
Edwin M. Graycochea
Keyword(s):  
Production Control ◽  
Film Material ◽  
Customer Complaints ◽  
Conductive Films ◽  
Peeling Test ◽  
Die Attach ◽  
Conductive Film ◽  
Scanning Acoustic Microscope ◽  
Strength Improvement ◽  
Section Analysis

The absent of reliable production controls for Die Attach Film (DAF) voids detection allowed defect escapee for Ball Grid Array (BGA) devices using non-conductive film material leading to gross assembly rejection and customer complaints. This paper presents the evaluation of pressure curing as an alternative to the convection curing in die attach process with additional capability to eliminate the DAF voids on non-conductive films. Through Analysis of Variance (ANOVA) analysis, green peeling test, Scanning Acoustic Microscope (SAM), cross section analysis and reliability test performed between samples arrives to the conclusion that pressure oven has a significant impact in die shear strength improvement and DAF voids elimination with positive response in reliability requirement. The result of the study improves the assembly flow and production control of BGA devices through the transition of convection to pressure curing technology.

Silicon Carbide Die Attach Scheme for 500°C Operation

2000 ◽  
Vol 622 ◽  
Author(s):  
Liang-Yu Chen ◽  
Gary W. Hunter ◽  
Philip G. Neudeck
Keyword(s):  
Silicon Carbide ◽  
High Temperature ◽  
Electrical Resistance ◽  
Room Temperature ◽  
Semiconductor Devices ◽  
Single Crystal Silicon ◽  
Film Material ◽  
Crystal Silicon ◽  
Pure Alumina ◽  
Die Attach

ABSTRACTSingle crystal silicon carbide (SiC) has such excellent physical, chemical, and electronic properties that SiC based semiconductor electronics can operate at temperatures in excess of 600°C well beyond the high temperature limit for Si based semiconductor devices. SiC semiconductor devices have been demonstrated to be operable at temperatures as high as 600°C, but only in a probe-station environment partially because suitable packaging technology for high temperature (500°C and beyond) devices is still in development. One of the core technologies necessary for high temperature electronic packaging is semiconductor die-attach with low and stable electrical resistance. This paper discusses a low resistance die-attach method and the results of testing carried out at both room temperature and 500°C in air. A 1 mm2 SiC Schottky diode die was attached to aluminum nitride (AlN) and 96% pure alumina ceramic substrates using precious metal based thick-film material. The attached test die using this scheme survived both electronically and mechanically performance and stability tests at 500°C in oxidizing environment of air for 550 hours. The upper limit of electrical resistance of the die-attach interface estimated by forward I-V curves of an attached diode before and during heat treatment indicated stable and low attach-resistance at both room-temperature and 500°C over the entire 550 hours test period. The future durability tests are also discussed.

Optical and electrical properties and simulation curves of NiO/Al/NiO transparent conductive film

2019 ◽  
Vol 33 (01) ◽  
pp. 1850417 ◽  
Author(s):  
Shuyun Wang ◽  
Kailin Wen ◽  
Yang Sun ◽  
Xianwu Xiu ◽  
Shuyun Teng ◽  
...  
Keyword(s):  
Electrical Properties ◽  
Metal Film ◽  
Room Temperature ◽  
Optical And Electrical Properties ◽  
Light Wavelength ◽  
Conductive Films ◽  
Conductive Film ◽  
Average Transmittance ◽  
Interface Characteristics ◽  
Experimental Data Analysis

In this paper, NiO/Al/NiO transparent conductive films were prepared by magnetron sputtering at the room temperature. Effects of the NiO and Al layers thicknesses on the optical and electrical properties of the NiO/Al/NiO laminated films were analyzed. When the light wavelength falls in range 300–900 nm, with the increase of the NiO and Al layers thicknesses, the transmittance of the laminated film first increases significantly and then decreases slightly, finally tends to be stable. The laminated film obtained the best optical and electrical properties when the NiO layer is 40 nm and the Al layer is 12 nm. The maximum transmittance is 83%, the average transmittance is 77.3%, the film resistivity is [Formula: see text] and the carrier concentration is [Formula: see text]. At the same time, the transmittance of laminated film is simulated by FDTD software. But the simulation curve is different from the experimental data. Analysis results show that, with the NiO dielectric is added on both sides of the metal Al film, the light reflection characteristic of laminated film has been completely different from that of the single Al metal film because of the change of interface characteristics between Al film and NiO film, and the actual luminous transmittance greatly increases.

A Joining Technique Using Multilayer Lead-Indium-Gold Composite Deposited In High Vacuum

1993 ◽  
Vol 314 ◽  
Author(s):  
Chin C. Lee ◽  
Chen-Yu Wang ◽  
Yi-Chia Chen ◽  
Goran Matijasevic
Keyword(s):  
Composite Solder ◽  
Electronic Devices ◽  
High Vacuum ◽  
Solution Phase ◽  
Solid Solution Phase ◽  
Shear Tests ◽  
Acoustic Microscope ◽  
Scavenging Effect ◽  
Die Attach ◽  
Scanning Acoustic Microscope

AbstractA joining technique for electronic devices has been developed. This technique uses a leadindium- gold multilayer composite solder deposited directly on GaAs wafers in high vacuum to prevent indium oxidation. The gold layer on the composite further protects the indium layer from oxidation in atmosphere. The GaAs dies are bonded to a gold-coated alumina substrate at a process temperature of 250°C. Nearly perfect joints are achieved as verified by a scanning acoustic microscope (SAM). SEM and EDX results indicate that the alloy joint consists of AuIn2 grains embedded in an In-Pb solid solution phase, as predicted from the Au- In-Pb phase diagram. Compared to lead-tin solder, indium-lead solder has been shown by others to exhibit much better fatigue resistance and have much less of a scavenging effect. Thermal shock as well as shear tests confirm that a good die attach is obtained with the leadindium- gold composite.

A low-cost, highly-conductive polyvinyl alcohol flexible film with Ag-microsheets and AgNWs as fillers

RSC Advances ◽  
2016 ◽  
Vol 6 (84) ◽  
pp. 80905-80909 ◽  
Author(s):  
Yongyun Mao ◽  
Junmei Guo ◽  
Changyi Hu ◽  
Hongwei Yang ◽  
Yuwen Yang ◽  
...  
Keyword(s):  
Polyvinyl Alcohol ◽  
Low Cost ◽  
High Conductivity ◽  
Conductive Films ◽  
Flexible Film ◽  
Conductive Film ◽  
Ag Nanowires

Low-cost, high-conductivity flexible conductive films were fabricated using Ag-microsheets, Ag-nanowires (AgNWs) and polyvinyl alcohol (PVA) as conducting agents. The flexible conductive film shows good conductivity under stretching.

scholarly journals Fibers and Conductive Films Using Silver Nanoparticles and Nanowires by Near-Field Electrospinning Process

2015 ◽  
Vol 2015 ◽  
pp. 1-5 ◽  
Author(s):  
Cheng-Tang Pan ◽  
Tsung-Lin Yang ◽  
Yi-Chian Chen ◽  
Cherng-Yuh Su ◽  
Shin-Pon Ju ◽  
...  
Keyword(s):  
Thin Films ◽  
Silver Nanoparticles ◽  
Sheet Resistance ◽  
Silver Nanowires ◽  
Near Field ◽  
Electrospinning Process ◽  
Conductive Films ◽  
Conductive Film ◽  
The Future ◽  
Transparent Conductive Electrodes

The silver nanowires (AgNWs) and silver nanoparticles (AgNPs) were synthesized. With near-field electrospinning (NFES) process, fibers and thin films with AgNPs and AgNWs were fabricated. In the NFES process, 10 k voltage was applied and the AgNPs and AgNWs fibers can be directly orderly collected without breaking and bending. Then, the characteristics of the fibers were analyzed by four-point probe and EDS. The conductive film was analyzed. When the thickness of films with AgNWs and AgNPs was 1.6 µm, the sheet resistance of films was 0.032 Ω/sq which was superior to that of the commercial ITO. The transmissivity of films was analyzed. The transmissivity was inversely proportional to sheet resistance of the films. In the future, the fibers and films can be used as transparent conductive electrodes.

scholarly journals Die Attach Assembly Process Tool Advancement

2020 ◽  
pp. 46-49
Author(s):  
Frederick Ray Gomez ◽  
Rennier Rodriguez ◽  
Nerie Gomez
Keyword(s):  
Integrated Circuit ◽  
Precise Measurement ◽  
Production Control ◽  
Assembly Process ◽  
Conductive Adhesives ◽  
X Ray ◽  
Alternative Option ◽  
Die Attach ◽  
Control Robustness ◽  
Adhesive Thickness

Die attach film (DAF) voids detection is one of the challenges during the introduction of non-conductive adhesives for integrated circuit products affecting production control robustness and detection. In this paper, a specialized tool capable to distinguish and quantify the amount of DAF voids is presented wherein the implementation of semi-auto grid lines generates more precise measurement and correct defect call-out. The tool is proposed as an alternative option for x-ray inspection that is found to be incapable in proper detection and accurate measurement of gaps and un-occupied area within the adhesive thickness that produces over estimation of production rejects.

scholarly journals Formation of a conductive overcoating layer based on hybrid composites to improve the stability of flexible transparent conductive films

RSC Advances ◽  
2019 ◽  
Vol 9 (8) ◽  
pp. 4428-4434 ◽  
Author(s):  
Jin-geun Lee ◽  
Wonseok Cho ◽  
Youngno Kim ◽  
Hangyeol Cho ◽  
Hongjoo Lee ◽  
...  
Keyword(s):  
Hybrid Composites ◽  
Protective Layer ◽  
Silica Sol ◽  
Organic Polymer ◽  
Transparent Conductive Film ◽  
Transparent Conductive Films ◽  
Conductive Films ◽  
Conductive Film ◽  
The Stability

A protective layer that can be applied on a flat flexible transparent conductive film was prepared by combining silica sol and organic polymer.

Synthesis of ferrocenyl hyper-branched polyethylene for non-covalent dispersion of multi-walled carbon nanotubes and fabrication of flexible carbon nanotubes-based conductive films

RSC Advances ◽  
2016 ◽  
Vol 6 (35) ◽  
pp. 29663-29668 ◽  
Author(s):  
Zheng Deng ◽  
Li Wang ◽  
Haojie Yu ◽  
Xiaoting Zhai ◽  
Yongsheng Chen ◽  
...  
Keyword(s):  
Carbon Nanotubes ◽  
Branched Polyethylene ◽  
Conductive Films ◽  
Conductive Film ◽  
Multi Walled Carbon Nanotubes ◽  
Walled Carbon Nanotubes

Ferrocenyl hyper-branched polyethylene was found to be an efficient dispersant for dispersing MWCNTs in CHCl3 and for preparing a flexible conductive film.

scholarly journals Transparent Conductive Films of Copper Nanofiber Network Fabricated by Electrospinning

2015 ◽  
Vol 2015 ◽  
pp. 1-8 ◽  
Author(s):  
Sungyeoul Kim ◽  
Hyundong Lee ◽  
Dahye Kim ◽  
DaAe Ko ◽  
Dojin Kim ◽  
...  
Keyword(s):  
Copper Acetate ◽  
Polyvinyl Butyral ◽  
Copper Nitrate ◽  
Good Alternative ◽  
Formation Processes ◽  
X Ray Diffraction ◽  
Conductive Films ◽  
Annealing Temperatures ◽  
Conductive Film ◽  
Electrospinning Method

Cu nanofiber networks can be a good alternative of the Ag nanowire of high electrical conductivity while having the advantage of low price. An electrospinning method was developed to fabricate copper nanofiber network for use as a transparent conductive film on glass substrate. The effects of liquid diluents for electrospinning processability were examined in relation to the subsequent Cu nanofiber formation processes. Electrospinning solutions of copper acetate/polyvinyl alcohol (PVA) and copper nitrate trihydrate/polyvinyl butyral (PVB) were investigated. The polymer mixing solutions influenced the subsequent annealing temperatures for removal of the polymers and reduction of the formed CuO nanofibers to Cu metal nanofibers. The morphology and structures of the formed nanofiber networks were examined by scanning electron microscopy, energy dispersive spectroscopy, X-ray diffraction, and so forth. The mixture with PVB provided lower annealing temperatures suitable for application to flexible substrates.

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