Change Management


Excellence in the management of product and process changes allows ST to improve manufacturing efficiency, which benefit all the stakeholders.

Change management is a robust process in ST. The risks and benefits of any change proposal are evaluated as first step even before defining a qualification plan.

Our overriding aim is to guarantee product quality excellence to our customers for any product, for any process, in any factory.

Change management effectiveness is guaranteed through a well-defined process that drives compliance and allows for simple and effective execution, supported by a dedicated tool.

The change management process

The process consists of four steps:

  • Change proposal
  • Product/Process change assessment and classification
  • Qualification
  • Test, final approval and implementation


Each proposed change is evaluated, taking into consideration the effect on the product or application as well as the potential manufacturing impact. This is done through a feasibility study, experimental data analysis and risk analysis.


Change proposals are analyzed by the Product/ Process Change Review Board (PCRB). Particular emphasis is given by the risk assessment. This board is comprised of a multidisciplinary team of experts, including senior engineers and management, who evaluates then classifies, approves or rejects the change request. For each change, all potential impacts are evaluated.


To ensure that proposal changes do not affect the product or process performance, a list of tests is established for the qualification plan detailing the trials and actions required to qualify a change. It includes the acceptance criteria for trial lots during parametric tests, electrical wafer sort and final and reliability tests.


The Product/Process Change Review Board performs a final review of all results to approve or reject the implementation of the change.

All relevant documentation, such as manufacturing specifications, operating modes and control plans, is modified to take into account the change. Our processes and system track all changes and allow for cross- fertilization for same technology or products in different plants. Once implemented, the change is monitored with particular attention to ensure the results stay consistent over time.

Read the Quality Handbook (pdf, 4M) for more information.