Optimization of solder paste printability with laser inspection technique

Okura, T.; Kanai, Masayuki; Ogata, Shigeyuki; Takei, T.; Takakusagi, H.

doi:10.1109/iemt.1995.526187

Cited by 17 publications

(12 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The stencil printing process is paramount in producing high volume, low cost production, it does account for some 60% of assembly defects (Mangin, 1991). It is also estimated that up to 87% of reflow soldering defects are caused by stencil printing defects (Okuru et al, 1993). The stencil printing of pastes (illustrated in Fig.…”

Section: Introductionmentioning

confidence: 99%

Rheological characterisation of solder pastes and isotropic conductive adhesives used for flip-chip assembly

Durairaj

Mallik

Seman

et al. 2009

Journal of Materials Processing Technology

View full text Add to dashboard Cite

Section: Introductionmentioning

confidence: 99%

Rheological characterisation of solder pastes and isotropic conductive adhesives used for flip-chip assembly

Durairaj

Mallik

Seman

et al. 2009

Journal of Materials Processing Technology

View full text Add to dashboard Cite

“…Through it, the quality of solder printing can be controlled, and the printing process can be improved. The improvement covers the evaluation tools for achievement of optimal printing quality, including stencil design, printing parameters, kinds of solder paste [4,8,12,16,19]. (b) Chip mounter: Active chips (e.g.…”

Section: Soldering In Smtmentioning

confidence: 99%

Optimal combination of soldering conditions of BGA for halogen-free and lead-free SMT-green processes

Shu¹,

Hsu²,

Hu³

2012

Microelectronics Reliability

View full text Add to dashboard Cite

“…Second, adequate fringe contrast must be considered because it determines the quality of the intensity data, and accordingly the measuring accuracy of surface height. The fringe contrast is defined as , i.e., the ratio between the fringe modulation and the background intensity, and can be computed as [25] % (10) where , and are the sensed images of the four phases as in those defined in (4). If the fringe contrast is too low, the 3-D surface profile of the inspection object cannot be properly reconstructed.…”

Section: Region Segmentation Using a Fringe-contrast Thresholdingmentioning

confidence: 99%

“…Step 5) Segment solder bump regions using the fringe-contrast thresholding: The fringe-contrast function of each measured point on the flip-chip substrate is first derived with (10). The measured points with fringe-contrast values lower than the predetermined threshold are regarded as the region of flat and low-reflection substrate, and their surface height values are set to zero.…”

Section: E Measurement Proceduresmentioning

confidence: 99%

Full-Field 3-D Flip-Chip Solder Bumps Measurement Using DLP-Based Phase Shifting Technique

Yen

Tsai²,

Feng³

2008

IEEE Trans. Adv. Packag.

View full text Add to dashboard Cite

The flip chip, a type of chip mounting used in semiconductor devices, has become one of the most popular innovations in the semiconductor packaging industry. The height of flip-chip solder bumps ranges from 20 to 140 m with a required measurement accuracy of 2 m. Three-dimensional (3-D) measurement of flip-chip solder bumps is crucial to flip-chip manufacturing quality and process control. Currently, 3-D measurement systems for flip-chip solder bumps are mainly based on laser scanning techniques. However, they require a high implementation cost, and suffer from low inspection speed due to the physical line-scanning process. In this paper, a fast and cost-effective 3-D measurement system for flip-chip solder bumps is proposed. The proposed system is based on a phase shift technique, in which the phase is accurately shifted by a software-controlled grating using a digital light processing (DLP) unit that allows full-field measurement of a projected flip chip. The DLP unit can provide a higher fringe-contrast pattern at a faster changing time than a liquid crystal display (LCD) panel. Phase shift-based measurement systems require a calibrated system parameter, which is generally considered a fixed value in currently available methods. In this paper, adaptive parameter values, instead of a fixed value, are used to improve measurement accuracy. The proposed system also adopts a fringe-contrast thresholding to solve the pseudo-surface height problem for high reflective solder bumps and low reflective substrate in a flip chip. Experiments have shown that the 3-D measurement of flip-chip solder bumps is very efficient and effective with the proposed system. Computation time of the proposed 3-D measurement system for a 640 480 image that contains almost 500 solder bumps is less than 1 s, and measurement accuracy meets the required specification of 2 m.Index Terms-Flip chip, phase shifting technique, solder bump, three-dimensional measurement.

show abstract

Optimization of solder paste printability with laser inspection technique

Abstract: A ACTThis paper describes an evaluation technique for solder paste printability using a solder paste inspection system and

Cited by 17 publications

References 0 publications

Rheological characterisation of solder pastes and isotropic conductive adhesives used for flip-chip assembly

Rheological characterisation of solder pastes and isotropic conductive adhesives used for flip-chip assembly

Optimal combination of soldering conditions of BGA for halogen-free and lead-free SMT-green processes

Full-Field 3-D Flip-Chip Solder Bumps Measurement Using DLP-Based Phase Shifting Technique

Contact Info

Product

Resources

About