Inversion Semiconductor

Inversion Semiconductor is a San Francisco-based semiconductor equipment startup founded in 2024 that is developing a next-generation lithography platform. Lithography uses light to pattern circuit features onto silicon wafers; the company's approach centers on generating the required high-power, short-wavelength light with a compact particle accelerator rather than the tin-droplet plasma sources used in incumbent extreme ultraviolet (EUV) systems. The stated method is laser wakefield acceleration (LWFA), in which plasma waves driven by a high-power laser accelerate electrons to high energies over centimeters instead of the kilometers required by large accelerators such as those at CERN and SLAC — described by the company as shrinking particle accelerators 1000x.

The company's published performance targets include a 100% increase in transistor density for the same numerical aperture, 3x higher throughput per scanner with the ability to power multiple scanners from one source, a tunable source able to produce the 13.5nm EUV light used today and shorter wavelengths thereafter, and greater than 25% improvement in critical dimension uniformity for high-aspect-ratio features relevant to novel transistor architectures including quantum and reversible computing. Aggregate marketing framing across sources is "the most powerful chips 15x faster." A near-term goal cited in the YC launch post is 10 kW of shorter-wavelength light, compared with an ASML decade-scale target of 1 kW of EUV output for 1 MW of input power, and an interim milestone of 1 kW of soft x-ray light in the 20nm-6nm band.

Development to date includes a small laser lab in the basement of the Y Combinator office used to test laser stability algorithms, initial LWFA prototypes for generating short-wavelength light, and a research collaboration with Lawrence Berkeley National Laboratory and the Berkeley Lab Laser Accelerator (BELLA), named the Laser Undulator eXperiment (LUX) or BELLA-LUX. Planned next steps are a high-power tunable light source called STARLIGHT, novel mirror systems to reflect and focus the generated x-ray light, and a first silicon-patterning demonstration system called LITH-0.

Founding story

According to the Y Combinator launch post, about seven months before February 2025 Rohan Karthik was automating chip design in the systems group at Arm while finishing an MEng in Mechanical Engineering at Imperial College London, and Daniel Vega was building machine learning models for stability optimization of tabletop particle accelerators at CERN (AWAKE Run 2) while completing a master's in Applied Physics at University College London. They concluded that a novel lithography machine could be built by shrinking particle accelerators 1000x to create a high-power light source driven by laser wakefield acceleration. Vega had previously worked on particle accelerators for cancer treatment at Lumitron Technologies; Karthik had earlier built vision software for surgical robots at CMR Surgical and led the Karman Space Program. One aggregator profile states the founders met through the Entrepreneur First programme before joining Y Combinator.

Business model

B2B hardware manufacturing: the company intends to sell or provide access to lithography systems and high-power light sources for semiconductor fabrication. One source describes a single light source powering multiple lithography scanners, which the company frames as a revenue gain for fabs. An intermediate concept described in the YC launch post is a user facility where customers book beam time on the light source, likened to reserving a rocket launch by credit card; the company website carries a "Reserve yours today" contact call to action.

No revenue is described in the sources. Prospective monetization referenced includes sale of lithography systems and high-power light sources to fabs (with one source describing multiple scanners powered by a single source as unlocking billions in annual revenue gains for fabs) and a possible user facility where customers reserve beam time.

Traction

Pre-revenue and pre-product. Reported traction consists of an in-house mini laser lab used to test laser stability algorithms, initial LWFA prototypes generating small-wavelength light, a strategic research partnership with Lawrence Berkeley National Laboratory's BELLA Center (BELLA-LUX), participation in Y Combinator's Winter 2025 batch, a reported $500K raised, a team listed at 9 by Y Combinator, and stated interest from Tesla and Applied Materials in x-ray imaging and mask inspection applications.

Latest developments

As of the February 2025 YC launch post, the company had a mini laser lab in the YC office basement, initial LWFA prototypes, and the BELLA-LUX collaboration with Lawrence Berkeley National Laboratory, with next milestones being the STARLIGHT tunable high-power light source, novel x-ray mirror systems, and the LITH-0 silicon-patterning demonstrator. Aggregator sources report a $500,000 funding round dated variously March 2025 and April 2025. Y Combinator lists the company as active with a team size of 9; the company website carries a 2025 copyright notice.