The company making loudspeakers - and cooling fans - the way you make a microchip.
For about a hundred and forty years, the loudspeaker has worked the same way. You run current through a coil of wire, the coil sits in a magnetic field, and the current makes it push and pull a paper or plastic cone. The cone shoves air around, and the air, eventually, becomes the sound of someone telling you your call is important to them. It is a beautifully simple idea, and it is also, if you think about it, a tiny electric motor bolted to a piece of cardboard.
xMEMS, a company in Santa Clara, looked at that arrangement and asked a semiconductor question: what if you skipped the motor and the cardboard entirely and just etched the whole thing out of silicon? Their speakers have no voice coil and no cone. Instead they use the piezoelectric effect - apply a voltage to a piezo material, it flexes, and that flex drives a silicon membrane that moves air. The whole device is manufactured on a wafer, like a chip, which means it comes off the line with the consistency and scale of a chip. This is the entire pitch, and it is a good one, because "we make it like a semiconductor" is a sentence that has ended a lot of industries that used to make things by hand.
The practical payoff is that these speakers are extremely thin, extremely uniform from one unit to the next, and durable in ways a paper cone is not. xMEMS calls the underlying technology a piezoMEMS silicon platform, MEMS being micro-electro-mechanical systems, the family of tiny mechanical structures built with chip-fabrication tools. If you have used a phone with a fingerprint sensor or an accelerometer, you have already trusted MEMS with something. xMEMS' bet is that you will also trust it with music.
"xMEMS is at the heart of a significant shift in hardware design driven by AI. piezoMEMS will be a foundational building block for the AI hardware era."
There is a second act, and it is arguably stranger than the first. Having figured out how to make a silicon membrane pump air, xMEMS realized that a membrane that pumps air is, in a certain light, a fan. So they built one: the XMC-2400, a cooling device roughly one millimeter thin, with no spinning blades. It moves air silently and without vibration, and it is small enough to slip inside a phone, a pair of AI glasses, an SSD, or - in a plot twist for an earbuds company - an optical transceiver in an AI data center. They call it a "fan-on-a-chip," which is the kind of phrase that either makes engineers lean forward or roll their eyes, and in this case seems to be doing the former.
Voltage flexes a piezo layer, which drives an integrated silicon membrane to push air. No coil, no cone. Result: 1mm-thin, wafer-consistent drivers for earbuds, IEMs, hearing aids, headphones and AI glasses.
The same membrane, tuned to pump a directed airflow instead of sound. A 1mm, all-silicon, blade-free cooler - silent and vibration-free - for phones, wearables, SSDs and AI data-center optics.
The lineup reads like a nature trail - Montara, Cowell, Cypress, Sycamore, Skyline. Behind the pleasant names is a fairly aggressive set of "world's first" claims, most of which appear to check out.
Full-range solid-state MEMS drivers for IEMs, TWS earbuds and hearing aids. Montara Plus targets audiophile IEMs; Montara Pro adds active DynamicVent venting.
2022Billed as the world's smallest solid-state micro speaker, used as a high-frequency tweeter alongside a dynamic woofer. Now in mass production.
2023Full-range solid-state MEMS speaker for ANC earbuds that generates audible sound by modulating and demodulating ultrasound.
2024Solid-state active ambient vent control for TWS earbuds and hearing aids, balancing isolation against awareness on demand.
2024The first all-silicon, blade-free active micro-cooling fan, 1mm thin - for phones, AI glasses, SSDs and data-center optical transceivers.
2024The world's first 1mm-thin near-field, open-air, full-range MEMS loudspeaker for smartwatches, XR glasses/goggles and open-fit earbuds.
2025xMEMS doesn't sell you a gadget - it sells the part inside one. That makes it a B2B semiconductor supplier whose components show up in other companies' products. If you build one of these, xMEMS wants to be the speaker or the cooler:
In October 2025, xMEMS closed a $21M Series D led by Boardman Bay Capital Management, with Cloudview Capital, CDIB-TEN Capital, Harbinger Venture Capital and SIG Asia Investments joining. The money is earmarked for the least glamorous and most important thing a deep-tech company does: scaling manufacturing. Earlier backers include GGV Capital and SIG.
Bar heights illustrative of relative momentum; total ~$129M across four rounds. Valuation undisclosed.
"This fundraise comes at a moment of rapidly accelerating commercial momentum. We're expanding manufacturing and fueling the next wave of piezoMEMS innovation."
Joseph Jiang and co-founders set out to build loudspeakers as semiconductors on a piezoMEMS silicon platform, in Santa Clara.
The world's first all-silicon, monolithic MEMS micro speakers reach the market for in-ear audio.
Full-range drivers reach IEMs, TWS earbuds and hearing aids, including the first MEMS-speaker hearing aid.
The world's smallest solid-state micro speaker begins shipping as a high-frequency tweeter.
The 1mm XMC-2400 uCooling chip and the ultrasound-driven Cypress ANC speaker debut.
The 1mm near-field Sycamore is demoed at CES; uCooling reaches AI data centers; a $21M Series D funds scale-up.