2008 International Conference on Electronic Packaging Technology & High Density Packaging (ICEPT-HDP 2008)
978-1-4244-2740-6/08/$25.00 © 2008 IEEE
Qualification for Product Development
Weiqiang Wang, Michael H. Azarian and Michael Pecht
Center for Advanced Life Cycle Engineering (CALCE)
University of Maryland
College Park, MD 20742, USA
Email: pecht@calce.umd.edu;
Telephone number: (01)301-405-5323;
Fax number: (01)301-314-9269
Abstract
The aim of qualification is to verify whether a product
meets or exceeds the reliability and quality requirements of
its intended application. Qualification plays an important
role in the process of product development. It can be
classified by its specific purpose at different stages of the
product development process. In this paper, a new
methodology of product qualification is proposed based on
physics-of-failure. This methodology consists of: product
configuration and material information collection;
application requirement information collection; strength
limits and margins; failure modes, mechanisms and effects
analysis; definition of qualification requirements;
qualification test planning; testing; failure analysis and
verification; and quality and reliability assessment. This
approach to qualification ensures that it successfully
addresses the failure mechanisms applicable to the
product’s specific design, manufacture, and application
conditions.
1 Introduction
Qualification is the process of demonstrating that an
entity or process is capable of meeting or exceeding the
specified requirements [1]. Qualification includes activities
which ensure that the nominal design and manufacturing
process will meet or exceed the specified targets. The
purpose of qualification is to obtain the acceptable range of
variability for all critical product parameters affected by
design and manufacturing, such as geometric dimensions
and material properties. Attributes that fall outside the
acceptable range are termed as “defects” because they have
the potential to make the product fail to meet the specified
requirements [2].
Qualification can be used in process development and
product development. Process qualification involves a set
of procedures which validate that a process used to
manufacture a product meets specified performance
requirements [3]. It is used to provide assurance that a
particular process is under control and known to produce
qualified products [4]. Product qualification aims to
evaluate performance of products under specified
operating and environmental conditions within a specified
period of time, which will be the focus of this paper.
The performance of a product consists of quality
(which includes function) and reliability, whose
requirements are set during product design. The
qualification process is intended to examine whether the
products’ performance can meet the design requirements.
The product qualification includes the verification of
functions, the assessment of reliability in application
conditions, and the validation in the system application if
the product is a component of a system.
Product qualification can be used to baseline the
design, materials and processes. It determines the product
performance degradation under normal application
conditions. It can also be used to compare different designs
to help make design decisions. Product qualification is
used to meet the requirements of customers with
consideration of the intended application and application
conditions.
2 Qualification in product development process
Qualification occurs in different stages of the product
development process, as shown in Figure 1. Qualification
activities in different stages have different purposes.
Virtual qualification is to evaluate the functional and
reliability performance of the product design without any
physical testing on the product. Virtual qualification
involves using computer-assisted modeling and simulation
based on physics-of-failure (PoF) [5]. Product qualification
is to evaluate the product based on the physical testing on
the manufactured prototype. The purpose is to verify
whether the product has met or exceeded its intended
quality and reliability requirements. After virtual and
product qualification, the products are mass produced.
During and after the manufacturing process, the products
can be inspected and tested to evaluate their quality and
defected parts can be screened out. This process can be
considered as a third stage in the overall qualification
process, and it is more commonly referred to as quality
assurance testing.
Virtual and product qualification efforts are part of a
larger process of product design and development. At
various intersections of the process, maturity levels can be
assigned to indicate progress and specific readiness for the
next phase. The design and product qualification process
may include feedback iterations shown in Figure 2. If the
product design is found to be unqualified during the virtual
qualification process, it is modified and then virtually re-
qualified before proceeding to the next phase. Similarly,
when a design has successfully passed through the virtual
qualification process, but does not meet the qualification
requirements during product qualification stage, feedback
iterations may be necessary. In this case, the virtual
qualification process and specifically, the physics-of-
failure based models may have to be re-evaluated and
modified. After design completion, the product is
manufactured in high volume and subjected to quality
assurance testing during and after the process.