A novel method and device for solder joint quality inspection by using laser ultrasound

2002 ◽  
Author(s):  
Sheng Liu ◽  
D. Erdahl ◽  
C. Ume ◽  
A. Achari
Keyword(s):  
Solder Joint ◽  
Laser Ultrasound ◽  
Quality Inspection ◽  
Novel Method ◽  
Joint Quality

Vibration Analysis Based Modeling and Defect Recognition for Flip Chip Solder Joint Inspection

2000 ◽  
Author(s):  
Sheng Liu ◽  
Dathan Erdahl ◽  
I. Charles Ume
Keyword(s):  
Solder Joint ◽  
Vibration Analysis ◽  
Flip Chip ◽  
Process Development ◽  
Great Promise ◽  
Quality Inspection ◽  
Vibration Frequencies ◽  
Vibration Responses ◽  
Solder Joint Inspection ◽  
Joint Quality

Abstract A novel approach for flip chip solder joint quality inspection based on vibration analysis is presented. Traditional solder joint inspection methods have their limitations when applied to flip chip solder joint quality inspection. The vibration detection method is a new approach which has advantages such as being non-contact, non-destructive, fast and can be used on-line or during process development. In this technique, a flip chip was modeled as a thick plate supported by solder bumps. Changes in solder joint quality produce different vibration responses of flip chip, and change its natural vibration frequencies. In this paper, the vibration frequencies of a flip chip on a ceramic substrate were calculated using the finite element method. Based on vibration analysis, a laser ultrasound and interferometric system was developed for flip chip solder joint quality inspection. In this system, chips with good solder joints can be distinguished from chips with bad joints using their vibration responses and frequencies. Defects recognition methods were developed and tested. Results indicate this approach offers great promise for solder bump inspection in flip chip, BGA and chip scale packages.

Board-Level Solder Joint Reliability Study of Land Grid Array Packages for RF Application Using a Laser Ultrasound Inspection System

2010 ◽  
Vol 132 (2) ◽  
Author(s):  
Jin Yang ◽  
Lizheng Zhang ◽  
I. Charles Ume ◽  
Camil Ghiu ◽  
George White
Keyword(s):  
Solder Joint ◽  
Thermal Cycling ◽  
Thermal Loading ◽  
Inspection System ◽  
Laser Ultrasound ◽  
Solder Joint Reliability ◽  
Joint Reliability ◽  
Joint Quality ◽  
Ultrasound Inspection ◽  
Board Level

Microelectronics packaging technology has evolved from through-hole, and bulk configuration to surface-mount, and small-profile ones. Today’s electronics industry is also transiting from SnPb to Pb-free to meet environmental requirements. Land grid array (LGA) package has been becoming popular in portable electronics in terms of low profile on the printed wiring boards and direct Pb-free assembly process compatibility. With the package profile shrinking and operating power increasing, solder joint quality and reliability has become a major concern in microelectronics manufacturing. The solder joint failure at the package level or board level will cause electronic devices not to function during service. In this paper, board-level solder joint reliability of the LGA packages under thermal loading is studied through thermal cycling tests. A novel laser ultrasound-interferometric system developed by the authors is applied to inspect solder joint quality during the thermal cycling tests. While the laser ultrasound inspection technique has been successfully applied to flip chips and chip scale packages, this study is the first application of this technique to overmolded packages. In this study, it is found out that the LGA packages can withstand 1000 temperature cycles without showing crack initiation or other failure mechanisms in the solder joints. The laser ultrasound inspection results match the visual observation and X-ray inspection results. This study demonstrates the feasibility of this system to solder joint quality inspection of overmolded packages. In particular, the devices constituting the objective of this study are radio frequency modules, which are encapsulated through overmolding and are mounted on a typical four-layer FR4 board through LGA terminations.

Vibration Analysis Based Modeling and Defect Recognition for Flip-Chip Solder-Joint Inspection

2002 ◽  
Vol 124 (3) ◽  
pp. 221-226 ◽  
Author(s):  
Sheng Liu ◽  
I. Charles Ume
Keyword(s):  
Solder Joint ◽  
Vibration Analysis ◽  
Flip Chip ◽  
Great Promise ◽  
Quality Inspection ◽  
Vibration Frequencies ◽  
Vibration Responses ◽  
Solder Joint Inspection ◽  
Defect Recognition ◽  
Joint Quality

A novel approach for flip-chip solder joint quality inspection based on vibration analysis is presented. Traditional solder joint inspection methods have their limitations when applied to flip chips. The vibration detection method is a new approach which has advantages such as being non-contact, non-destructive, accurate, fast and applicable for in-line inspection or during process development. In this technique, a flip chip was modeled as a thick plate supported by solder bumps. Changes in solder joint quality produce different flip chip vibration responses, and also change its natural vibration frequencies. In this paper, the vibration frequencies of a flip chip on a ceramic substrate were calculated using the finite element method. Based on vibration analysis, a laser ultrasound and interferometric system was developed for flip chip solder joint quality inspection. In this system, chips with good solder joints can be distinguished from chips with bad joints using their vibration responses and frequencies. Data analysis and defect recognition methods were developed and tested. Results indicate this approach offers great promise for solder bump inspection in flip chip, BGA, and chip scale packages.

Sign in / Sign up

Export Citation Format

Share Document