Shares of Aehr Test Systems Inc. (AEHR) surged in premarket trading Wednesday after the semiconductor test equipment maker reported fiscal fourth-quarter results that topped Wall Street estimates and issued fiscal 2027 revenue guidance well above expectations.

The company reported fourth-quarter earnings of 11 cents per share, beating analysts' expectations for a loss of 1 cent, according to market data. Revenue rose to $18.84 million from $14.09 million a year earlier, topping the consensus estimate of $18.69 million.

Aehr's business has become significantly more diversified. While more than 95% of revenue was previously tied to silicon carbide applications for electric vehicles, nearly 95% of fiscal 2026 revenue came from markets outside that segment.

Fourth-quarter bookings jumped more than fivefold to $60.7 million from $11.1 million a year earlier, driven by demand for its Sonoma and FOX burn-in systems, WaferPaks, module boards, and AI processor and silicon photonics testing applications.

The company ended the fiscal year with a record backlog of $80.6 million. Including approximately $20 million in orders received after year-end, its effective backlog increased to about $100.6 million. Cash, cash equivalents and restricted cash totaled $116.5 million at fiscal year-end.

During the quarter, Aehr completed more than 12 gallium nitride (GaN) WaferPak designs that are now undergoing customer evaluations. Management expects most of those designs to enter production, supporting demand for its wafer-level burn-in systems in fiscal 2027 and beyond.

The company also introduced what it said is the industry's first 300-millimeter GaN wafer-level burn-in solution using high-voltage WaferPaks for high-temperature reverse-bias testing. It completed its first FOX wafer-level burn-in system sale for silicon MOSFET applications, broadening the platform beyond silicon carbide and GaN technologies.

Aehr added its first silicon carbide customer in Taiwan and secured about $8 million in new silicon carbide wafer-level burn-in orders over the past month, citing accelerating global electric vehicle programs.

Looking ahead, the company forecast fiscal 2027 revenue of $130 million to $150 million, well above the analyst consensus estimate of $85.13 million. The outlook implies revenue growth of roughly 2.6 times to 3 times compared with fiscal 2026.

Management said guidance could increase if additional customer orders are secured, supported by its record backlog. The company also said it does not expect manufacturing capacity constraints even if revenue reaches the high end of its guidance range.

Aehr expects a non-GAAP pre-tax margin of 18% to 22% in fiscal 2027. It also forecast continued growth in AI semiconductor testing and optical devices, along with a recovery in silicon carbide and gallium nitride testing demand driven by automotive electrification and AI data center power infrastructure investments.

The company said it continues expanding its FOX wafer-level burn-in platform into new end markets, with potential customer orders expected in fiscal 2027 and production ramps beginning as early as fiscal 2028.

CEO Gayn Erickson said artificial intelligence will become an even larger driver of Aehr Test Systems' business in fiscal 2027, with AI expected to account for a bigger share of both revenue and sales mix.

"AI is going to be a big chunk of our business this year, both in dollars and percentage," he said.

He said the company's growth outlook is supported by expanding orders from existing AI customers, increasing production ramps, and continued demand for wafer-level and package-level burn-in solutions used in AI processors, accelerators and data center infrastructure.

Management also noted that its current fiscal 2027 guidance is largely based on existing customers, with additional AI opportunities potentially providing further upside.

AEHR Price Action: Aehr Test System shares were up 29.79% at $93.46 during premarket trading on Wednesday, according to market data.