onsemi's 'Fab Right' Pivot: A High-Stakes Bet on Specialization

SCOTTSDALE, Ariz. – July 07, 2026 – In a decisive move that signals a broader strategic shift within the semiconductor industry, onsemi today announced the sale of two major manufacturing facilities in Tarlac, Philippines, and Mountain Top, Pennsylvania. The divestitures are the latest and most significant public step in the company's 'Fab Right' strategy, an ambitious initiative to streamline global operations and sharpen its focus on high-margin, intelligent power and sensing technologies. The deals, which will transfer ownership to Taiwan's Greatek Electronics Inc. and Sweden's Silex Microsystems respectively, are projected to yield approximately $35 million in annual cost savings. While onsemi frames the move as a crucial step toward a more competitive and efficient future, the transactions create a complex ripple effect, raising questions about local economies and reshaping segments of the global semiconductor supply chain.

The 'Fab Right' Blueprint for a Leaner onsemi

The divestitures are not an isolated cost-cutting measure but the cornerstone of a multi-year transformation. The 'Fab Right' strategy, as detailed by company leadership in investor presentations, is a continuous process of optimizing onsemi’s manufacturing footprint to be more asset-light and agile. The goal is to divest or repurpose less competitive facilities and concentrate capital on vertically integrated, high-growth areas like Silicon Carbide (SiC) manufacturing, which is critical for the automotive and industrial markets. This strategy was born from a need to navigate challenging business conditions and lower inventory to a leaner target of 100-120 days, according to CEO Hassane El-Khoury in a 2025 presentation.

By shedding the Tarlac and Mountain Top fabs, the Scottsdale-based chipmaker aims to drive sustained gross margin expansion and create what it calls a “highly efficient manufacturing network.” The financial markets have offered a measured response. On the day of the announcement, onsemi’s stock (NASDAQ: ON) saw a modest 2.4% dip in pre-market trading. This reaction comes even as the stock has surged an impressive 75% year-to-date, with dozens of analysts recently revising earnings estimates upward. The company’s high valuation, reflected in a P/E ratio of over 67x, suggests investors have already priced in significant future growth, and this strategic pivot is a key test of management’s ability to deliver on that promise. The projected $35 million in annual savings, fully realized by 2028, represents a tangible step toward bolstering the bottom line.

New Owners, New Frontiers

The acquiring companies, Greatek Electronics and Silex Microsystems, are not passive buyers but strategic players seizing an opportunity to expand their specialized niches. Their respective plans for the facilities highlight the increasing specialization within the semiconductor ecosystem.

Greatek Electronics, a Taiwan-based specialist in integrated circuit (IC) packaging and testing, will take over the Tarlac, Philippines facility. With over half its revenue coming from assembly services, the acquisition is a direct play to expand its capacity in Southeast Asia. This move aligns perfectly with the “Taiwan Plus One” strategy, a supply chain diversification push demanded by major global clients looking to reduce geopolitical risk. Backed by Powertech Technology Inc., the world's largest memory chip testing and packaging provider, Greatek is well-positioned to integrate the Tarlac site into its growing network. The transaction, expected to close within six months, will strengthen its service offerings and regional footprint.

Meanwhile, Silex Microsystems, the world's leading pure-play Micro-Electro-Mechanical Systems (MEMS) foundry, is acquiring the Mountain Top, Pennsylvania site for a different strategic purpose. For a purchase price of $40 million, the Swedish firm gains its first U.S. manufacturing footprint. Silex plans a substantial investment of approximately $150 million (SEK 1.6 billion) to convert the existing integrated circuit plant into a state-of-the-art MEMS fab. This move is designed to bring Silex closer to its American customer base, shorten lead times, and mitigate supply chain vulnerabilities. The company, which recently went public on Nasdaq Stockholm, is betting that a U.S. presence will be a powerful competitive advantage in high-value markets like medical devices, autonomous vehicles, and cloud infrastructure. Silex projects the new U.S. fab will reach break-even between 2029 and 2030, signaling a long-term commitment to the site and the region.

The Human and Economic Ripple Effect

Beyond the corporate strategy and financial metrics lies the human impact on the communities of Tarlac and Mountain Top. While onsemi focuses on optimizing its global network, hundreds of employees face a period of transition and uncertainty. Active job postings at both locations confirm they are currently bustling centers of operation.

In Tarlac, the relatively quick three-to-six-month closing window creates an immediate sense of change. onsemi has secured a long-term supply agreement with Greatek, which suggests a need for operational continuity. However, specific details regarding job security for the existing workforce under the new ownership remain undisclosed. Workers at the assembly and testing facility will be watching closely to see how Greatek’s integration plans affect their roles.

In Mountain Top, the timeline is dramatically different. The extended transition period until January 2028 provides a longer runway but also prolongs uncertainty. onsemi plans an “orderly transfer” of its current product lines to other facilities, effectively winding down its operations at the site. Silex will simultaneously begin converting the plant for MEMS manufacturing, a process that involves different technologies and skill sets. This long-term plan may offer opportunities for some onsemi employees to be retrained for the new MEMS operations or to transfer within onsemi's network, but a direct one-for-one transition is unlikely. The shift from traditional semiconductor manufacturing to specialized MEMS production will fundamentally alter the employment landscape at the facility, creating a new set of demands on the local workforce.

Fortifying the Supply Chain Through Specialization

Viewed from a wider lens, these divestitures represent a case study in the evolution of the global semiconductor supply chain. The moves are more than a simple asset sale; they are a strategic realignment where companies double down on their core competencies. onsemi sheds legacy manufacturing to focus on designing and producing high-value intelligent power and sensing solutions. In turn, specialized leaders like Greatek (in packaging) and Silex (in MEMS) acquire the infrastructure to deepen their own competitive moats.

To prevent disruption, onsemi has put careful continuity measures in place. The long-term supply agreement with Greatek ensures that customers relying on products from the Tarlac facility will experience a seamless transition, with production continuing under the new, specialized ownership. For the Mountain Top facility, the extended two-year transition allows onsemi ample time to migrate its product manufacturing to other qualified sites within its own network before Silex takes full operational control. This methodical approach is designed to protect customer relationships and maintain supply chain integrity.

This trend toward specialization may ultimately foster a more resilient and efficient industry, where each player contributes its most advanced capabilities. By focusing its resources, onsemi is betting it can innovate faster in its target markets, while its former facilities gain new life under owners who see them as central to their own growth.