Y. H. Hung

Service quality evaluation by service quality performance matrix

Excellent service quality and high customer satisfaction is the key issue and challenge for todays service industry. Customer perception (satisfaction) and customer expectation (importance) determines the service quality performance. Questionnaires help service providers to realize their service quality performance, and the weighted average of customer satisfaction and the associated variance are commonly used indices reflecting customer expectation and customer percep tion. To evaluate, effectively and efficiently, service quality performance, this paper aims to portray customer expectation and customer satisfaction by assuming that the evaluation scales for expectation and satisfaction are between 0 and 1. This paper defines a customer satisfaction index and a customer expectation index based on the two parameters of a beta distribution, and the unbiased estimators for these two indices are provided. A standardized Service Quality Performance Matrix helps managers realize the service quality performance for important service elements with respect to the locations of the satisfaction index and the expectation index on the Service Quality Performance Matrix to propose adequate service quality improvement plans and strategies.

Integrated process capability analysis with an application in backlight module

Backlight application specializes in supplying light, with notable examples including liquid crystal display (LCD), hand-phone LCD, and PDA LCD. The integrated process capability and integrated process yield for cold cathode fluorescent lamp backlight are unknown. Process capability analysis is a highly effective means of assessing the process ability of backlight that meets specifications. A larger process capability index (PCI) implies a higher process yield, and lower expected process loss. Chen et al. [Int. J. Product. Res. 39 (2001) 4077], applied indices Cpu, Cpl, and Cpk to evaluate the integrated process capability for a multi-process product with smaller-the-better, larger-the-better, and nominal-the-best specifications, respectively. However, Cpk suffers from the weakness of being unable to reflect the specific process yield. This study selects index Cps to replace Cpk. Meanwhile, an integrated PCI for the entire backlight module is proposed, and the relationship between the PCI and process yield is described. A multi-process capability analysis chart, which reasonably accurately indicates the status of process capability for the backlight module, is designed for practical applications.

A neural network classifier with rough set-based feature selection to classify multiclass IC package products

The choice of packaging type is important to the process of researching and developing an integrated circuit (IC). Indeed, for an IC chip designer, the importance can be compared to an architects choice of construction design. Since there are considerable variations in characteristics and in the types of products available, collecting information about packaging technologies and products can be difficult and time-consuming. Therefore, finding the means to provide packaging information to designers quickly and efficiently is necessary and important, as this will not only help designers accurately decide on design methods for an IC, but also significantly reduce processing risks. In this study, existing product information, such as the dimensions, characteristics and design and application criteria, of a product was analyzed. One of the biggest issues when data from multi-dimensional measurements are represented as a feature vector is that the feature space of the raw data often has very large dimensions. This study explores the use of rough set attribute reduction (RSAR) to reduce attributes of the IC package family dataset, and artificial neural networks, to construct an efficient IC package type classifier model. The experimental results show that the features produced by RSAR improve on generalization accuracy: the training and testing set classification accuracy rates were 96.9% and 98.2%, respectively.

Process capability analysis chart with the application of Cpm

Process capability analysis (PCA) is a highly effective means of assessing the process ability of product that meets specifications. The process capability analysis chart (PCAC/Cpk ) evaluates the capabilities of multiprocess products together with nominal-the-best specifications, larger-the-better and smaller-the-better specifications. This study proposes process capability analysis chart (PCAC/Cpm ) to consider process yield and expected process loss. A new generated estimator for Cpm is proposed and the properties of statistical estimator and hypothesis test are discussed. A practical example was given for application.

Combining radial basis function neural network and genetic algorithm to improve HDD driver IC chip scale package assembly yield

In recent years, the future trend of micro HDD driver IC for large capacity micro HDD is to become lighter, thinner, shorter and smaller. Among all the options available for micro HDD driver ICs assembly, warpage is an important issue related to micro HDD driver IC manufacturability and reliability. The optimal packaging manufacturing process for driver IC for micro HDD is chip scale package (CSP). However, the production and assemble process for CSP is much more difficult. The aim of this study is to improve the lower warpage properties for 0.65mm CSP assembly yield using a model based on a radial basis function network (RBFN), and the optimal HDD packaging process parameter design is achieved through a genetic algorithm (GA).

Optimizing the controller IC for micro HDD process based on Taguchi methods

The future trend of controller integrated circuit (IC) for micro hard disk driver (HDD) is to be lighter, thinner, shorter and smaller. The storage capacity and unit cost of micro HDD is lower than of flash memory card. The optimal packaging manufacturing process for driver IC for micro HDD is Chip Scale Package (CSP). However, the production and assemble process for CSP is much more difficult. Especially, the warpage problem on modeling results in non-conforming products. This research is to discover the optimal production levels for control factors based on the orthogonal array in Tachugi method. The product size used in the study is the driver IC package overall height less than 0.65 mm for micro HDD with CSP manufacturing process.

Optimal process parameters design for a wire bonding of ultra‐thin CSP package based on hybrid methods of artificial intelligence

Purpose – The aim of this research is to combine the Taguchi method and hybrid methods of artificial intelligence, to use them as the optimal tool in wire bond designing parameters for an ultra‐thin chip scale package (CSP) package, and then construct a set of the optimal parameter analysis flow and steps.Design/methodology/approach – The hybrid methodology of artificial Intelligence was used in order to identify the optimum parameters design for a wire bonding of ultra‐thin CSP package. This paper employed desirability function to integrate two quality characteristics (loop height and wire pull strength) into a single quality indicator to construct a well‐trained neural network prediction system with hybrid genetic algorithm.Findings – The processes parameters of low‐loop of micro HDD driver IC were optimized with GA, thereby achieving the objective of improving process yield and robustness design of micro HDD driver IC.Practical implications – The engineers could quickly obtain the optimal production pr...

A Neural Network-Based Prediction Model in Embedded Processes of Gold Wire Bonding Structure for Stacked Die Package

The trend in the consumer electronics market is to offer lighter, smaller outline, and more functional products, especially for portable products. This trend has pushed electronic packages to be thinner, with a lower profile and with multiple chips in one package. When the package becomes thinner, the space of the package correspondingly becomes an important issue. In order to obtain higher density and thinner package, we have to develop an embedded gold wire bonding assembly technology. It provides a simple structure with a thick adhesive layer to fix the upper layer die and bottom layer die gold wire. The developed technology can use exactly the same die size as for wire bonding interconnections without any additional processing. All electrical connections of the upper and the lower die are achieved by wire bonding to the substrate, independently. We have performed this stacking assembly by precise control of the die attach film layer thickness and low wire loop shape.

IMPROVING THE PLASTIC BALL GRID ARRAY ASSEMBLY YIELD: A CASE STUDY

The plasma cleaning process cleaning the residual containments in the assembly processes is one of the major processes in the plastic ball grid arrays (PBGA) assembly processes. Especially, when there is any micron particle existed before wire bonding and molding, parts of nonconforming will increase. With the rapid growth in production, yield improvement to reduce the production cost is essential for PBGA industry. In fact, the plasma cleaning process before wire bonding and molding both enhances the PBGA yield and reduces the production cost effectively. This study combines neural network with Taguchi method to structure a well-trained prediction model, further searches for the optimal plasma cleaning parameter design through genetic algorithm, and finally enhances the process yield and production quality in a central Taiwan PBGA company.

Measuring Banking Operation Performance by Applying a Process Capability Index

Service quality is important when selecting a banking service. Many factors affecting service quality are not measurable, and it is difficult to consistently evaluate front-line personal operation performance in the banking system. Consequently, most of the banks use Methods Time Measurement (MTM-C) to improve banking operation quality and reduce customer service time. From the perspective of consumers, standardizing operation time is an important criterion when selecting a banking service, and the specification of banking service quality is in accordance with the process capability index Cpu applied in the manufacturing industry. The Cpu index is a powerful and effective tool for evaluating product quality or process performance. Hence, this paper attempts to measure banking operation quality via the process capability index Cpu, by setting standard operation times as an upper specification limits for each front-line operation item, and to provide useful information for the operations performance management in the banking system