Automated solder inspection technique for BGA-Mounted substrates by means of oblique computed tomography

Atsushi Teramoto, Takayuki Murakoshi, Masatoshi Tsuzaka, Hiroshi Fujita

Research output: Contribution to journalArticle

34 Citations (Scopus)

Abstract

High-density large-scale integration (LSI) packages such as ball grid arrays (BGAs) are being utilized in car electronics and communication infrastructure products. These products require a high speed and reliable inspection technique for their solder joints. Oblique computed tomography (OCT) was proposed as a novel imaging technique for BGA-mounted substrates, and it is being introduced in many manufacturing factories. Although operators examine OCT images manually, the establishment of an automated inspection technique is required from the viewpoint of an operator's load and the fluctuation of the inspection results. In this paper, a novel automated solder inspection technique by means of OCT is proposed. This technique consists of position adjustment, bump extraction, character extraction and judgement. Moreover, by combining five characteristic features, the condition of a solder bump was determined in computer algorithm. In this paper, linear discriminate analysis and an artificial neural network technique are introduced as the determination methods. In the experiments, these techniques are evaluated by using actual BGA-mounted substrates. The correct rate of inspection reached 99.7% in both the determination methods, which clearly indicates that proposed method may be useful in practice.

Original languageEnglish
Pages (from-to)285-292
Number of pages8
JournalIEEE Transactions on Electronics Packaging Manufacturing
Volume30
Issue number4
DOIs
Publication statusPublished - 01-10-2007
Externally publishedYes

Fingerprint

Ball grid arrays
Soldering alloys
Tomography
Inspection
Substrates
LSI circuits
Industrial plants
Electronic equipment
Railroad cars
Neural networks
Imaging techniques
Communication
Experiments

All Science Journal Classification (ASJC) codes

  • Industrial and Manufacturing Engineering
  • Electrical and Electronic Engineering

Cite this

@article{1d7daf7f1e504901ac71f4a9b7fea435,
title = "Automated solder inspection technique for BGA-Mounted substrates by means of oblique computed tomography",
abstract = "High-density large-scale integration (LSI) packages such as ball grid arrays (BGAs) are being utilized in car electronics and communication infrastructure products. These products require a high speed and reliable inspection technique for their solder joints. Oblique computed tomography (OCT) was proposed as a novel imaging technique for BGA-mounted substrates, and it is being introduced in many manufacturing factories. Although operators examine OCT images manually, the establishment of an automated inspection technique is required from the viewpoint of an operator's load and the fluctuation of the inspection results. In this paper, a novel automated solder inspection technique by means of OCT is proposed. This technique consists of position adjustment, bump extraction, character extraction and judgement. Moreover, by combining five characteristic features, the condition of a solder bump was determined in computer algorithm. In this paper, linear discriminate analysis and an artificial neural network technique are introduced as the determination methods. In the experiments, these techniques are evaluated by using actual BGA-mounted substrates. The correct rate of inspection reached 99.7{\%} in both the determination methods, which clearly indicates that proposed method may be useful in practice.",
author = "Atsushi Teramoto and Takayuki Murakoshi and Masatoshi Tsuzaka and Hiroshi Fujita",
year = "2007",
month = "10",
day = "1",
doi = "10.1109/TEPM.2007.907574",
language = "English",
volume = "30",
pages = "285--292",
journal = "IEEE Transactions on Electronics Packaging Manufacturing",
issn = "1521-334X",
publisher = "Institute of Electrical and Electronics Engineers Inc.",
number = "4",

}

Automated solder inspection technique for BGA-Mounted substrates by means of oblique computed tomography. / Teramoto, Atsushi; Murakoshi, Takayuki; Tsuzaka, Masatoshi; Fujita, Hiroshi.

In: IEEE Transactions on Electronics Packaging Manufacturing, Vol. 30, No. 4, 01.10.2007, p. 285-292.

Research output: Contribution to journalArticle

TY - JOUR

T1 - Automated solder inspection technique for BGA-Mounted substrates by means of oblique computed tomography

AU - Teramoto, Atsushi

AU - Murakoshi, Takayuki

AU - Tsuzaka, Masatoshi

AU - Fujita, Hiroshi

PY - 2007/10/1

Y1 - 2007/10/1

N2 - High-density large-scale integration (LSI) packages such as ball grid arrays (BGAs) are being utilized in car electronics and communication infrastructure products. These products require a high speed and reliable inspection technique for their solder joints. Oblique computed tomography (OCT) was proposed as a novel imaging technique for BGA-mounted substrates, and it is being introduced in many manufacturing factories. Although operators examine OCT images manually, the establishment of an automated inspection technique is required from the viewpoint of an operator's load and the fluctuation of the inspection results. In this paper, a novel automated solder inspection technique by means of OCT is proposed. This technique consists of position adjustment, bump extraction, character extraction and judgement. Moreover, by combining five characteristic features, the condition of a solder bump was determined in computer algorithm. In this paper, linear discriminate analysis and an artificial neural network technique are introduced as the determination methods. In the experiments, these techniques are evaluated by using actual BGA-mounted substrates. The correct rate of inspection reached 99.7% in both the determination methods, which clearly indicates that proposed method may be useful in practice.

AB - High-density large-scale integration (LSI) packages such as ball grid arrays (BGAs) are being utilized in car electronics and communication infrastructure products. These products require a high speed and reliable inspection technique for their solder joints. Oblique computed tomography (OCT) was proposed as a novel imaging technique for BGA-mounted substrates, and it is being introduced in many manufacturing factories. Although operators examine OCT images manually, the establishment of an automated inspection technique is required from the viewpoint of an operator's load and the fluctuation of the inspection results. In this paper, a novel automated solder inspection technique by means of OCT is proposed. This technique consists of position adjustment, bump extraction, character extraction and judgement. Moreover, by combining five characteristic features, the condition of a solder bump was determined in computer algorithm. In this paper, linear discriminate analysis and an artificial neural network technique are introduced as the determination methods. In the experiments, these techniques are evaluated by using actual BGA-mounted substrates. The correct rate of inspection reached 99.7% in both the determination methods, which clearly indicates that proposed method may be useful in practice.

UR - http://www.scopus.com/inward/record.url?scp=35348820607&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=35348820607&partnerID=8YFLogxK

U2 - 10.1109/TEPM.2007.907574

DO - 10.1109/TEPM.2007.907574

M3 - Article

VL - 30

SP - 285

EP - 292

JO - IEEE Transactions on Electronics Packaging Manufacturing

JF - IEEE Transactions on Electronics Packaging Manufacturing

SN - 1521-334X

IS - 4

ER -