59‐2: Laser Reflow Soldering Technique for Mini/MicroLed Displays

2021 ◽  
Vol 52 (1) ◽  
pp. 830-832
Author(s):  
Lili Wang ◽  
Chuhang Wang ◽  
Chao Liu ◽  
Enkai Dong ◽  
Ming Zhai ◽  
...  
Keyword(s):  
Reflow Soldering

Signature Analysis of Package Delamination Using Scanning Acoustic Microscope

1996 ◽  
Author(s):  
S.X. Li ◽  
K. Lee ◽  
J. Hulog ◽  
R. Gannamani ◽  
S. Yin
Keyword(s):  
Failure Analysis ◽  
Early Stage ◽  
Signature Analysis ◽  
Acoustic Microscope ◽  
Reflow Soldering ◽  
Moisture Expansion ◽  
Scanning Acoustic Microscope ◽  
Package Reliability

Abstract Package delaminations are often associated with electrical and package reliability problems in IC devices. Delaminations caused by electrical-over-stress (EOS) and moisture expansion during reflow soldering have shown different delamination patterns. A Scanning Acoustic Microscope (SAM) can be used to detect package delaminations. Understanding these delamination signatures can help us quickly identify the failure cause at an early stage of the failure analysis.

scholarly journals Joining of Electrodes to Ultra-Thin Metallic Layers on Ceramic Substrates in Cryogenic Sensors

Sensors ◽  
2021 ◽  
Vol 21 (14) ◽  
pp. 4919
Author(s):  
Marcin Lebioda ◽  
Ryszard Pawlak ◽  
Jacek Rymaszewski
Keyword(s):  
Cryogenic Temperatures ◽  
Thermal And Mechanical Properties ◽  
Reflow Soldering ◽  
Ceramic Substrates ◽  
Temperature Range ◽  
Wave Soldering ◽  
Materials Used ◽  
Standard Designs ◽  
Electrical Connections ◽  
Method Show

Microjoining technologies are crucial for producing reliable electrical connections in modern microelectronic and optoelectronic devices, as well as for the assembly of electronic circuits, sensors, and batteries. However, the production of miniature sensors presents particular difficulties, due to their non-standard designs, unique functionality and applications in various environments. One of the main challenges relates to the fact that common methods such as reflow soldering or wave soldering cannot be applied to making joints to the materials used for the sensing layers (oxides, polymers, graphene, metallic layers) or to the thin metallic layers that act as contact pads. This problem applies especially to sensors designed to work at cryogenic temperatures. In this paper, we demonstrate a new method for the dynamic soldering of outer leads in the form of metallic strips made from thin metallic layers on ceramic substrates. These leads can be used as contact pads in sensors working in a wide temperature range. The joints produced using our method show excellent electrical, thermal, and mechanical properties in the temperature range of 15–300 K.

Ball Grid Array Thermomechanical Response During Reflow Assembly

1996 ◽  
Vol 118 (4) ◽  
pp. 214-222 ◽  
Author(s):  
T. E. Voth ◽  
T. L. Bergman
Keyword(s):  
Process Model ◽  
Experimental Studies ◽  
Ball Grid Array ◽  
Mechanical Processing ◽  
Processing Conditions ◽  
System Behavior ◽  
Reflow Soldering ◽  
Thermomechanical Response ◽  
Model Predictions ◽  
Representative System

The thermomechanical response of ball-grid array assemblies during reflow soldering is considered here. Experiments are performed to investigate the thermomechanical response of a representative system and the results are used to validate a numerical model of system behavior. The conclusions drawn from the experimental studies are used to guide development of a process model capable of describing more realistic BGA soldering scenarios. Process model predictions illustrate the system’s thermomechanical response to thermal and mechanical processing conditions, as well as component properties. High thermal conductivity assemblies show the greatest sensitivity to mechanical loading conditions.

Numerical simulation of self-alignment of chip resistor components for different silver content during reflow soldering

2017 ◽  
Vol 79 ◽  
pp. 69-78 ◽  
Author(s):  
A.M. Najib ◽  
M.Z. Abdullah ◽  
A.A. Saad ◽  
Z. Samsudin ◽  
F. Che Ani
Keyword(s):  
Numerical Simulation ◽  
Silver Content ◽  
Reflow Soldering

X-ray inspection and Six-Sigma in analysis of LED thermal pad coverage

2017 ◽  
Vol 29 (1) ◽  
pp. 28-33 ◽  
Author(s):  
Barbara Dziurdzia ◽  
Janusz Mikolajek
Keyword(s):  
Six Sigma ◽  
Vapour Phase ◽  
Inspection System ◽  
Solder Paste ◽  
Process Variables ◽  
Reflow Soldering ◽  
Content Type ◽  
X Ray ◽  
Solder Pastes ◽  
Free Solder

Purpose The purpose of this paper is to evaluate selected methods of reduction voidings in lead-free solder joints underneath thermal pads of light-emitting diodes (LEDs), using X-ray inspection and Six Sigma methodology. Design/methodology/approach On the basis of cause and effect diagram for solder voiding, the potential causes of voids and influence of process variables on void formation were found. Three process variables were chosen: the type of reflow soldering, vacuum incorporation and the type of solder paste. Samples of LEDs were mounted with convection and vapour phase reflow soldering. Vacuum was incorporated into vapour phase soldering. Two types of solder pastes OM338PT and LFS-216LT were used. Algorithm incorporated into X-ray inspection system enabled to calculate the statistical distribution of LED thermal pad coverage and to find the process capability index (Cpk) of applied soldering techniques. Findings The evaluation of selected soldering processes of LEDs in respect of their thermal pad coverage and statistical Cpk indices is presented. Vapour-phase soldering with vacuum is capable (Cpk > 1) for OM338PT and LFS-216LT paste. Convection reflow without vacuum with LFS-216LT paste is also capable (Cpk = 1.1). Other technological soldering processes require improvements. Vacuum improves radically the capability of a reflow soldering for an LED assembly. When vacuum is not accessible, some improvement of capability to a lower extent is possible by an application of void-free solder pastes. Originality/value Six Sigma statistical methodology combined with X-ray diagnosis was used to check whether applied methods of void reduction underneath LED thermal pads are capable processes.

Sign in / Sign up

Export Citation Format

Share Document