Kioxia Targets Automotive Applications With New Embedded Flash Memory

Kioxia recently introduced a new embedded flash memory compliant with UFS version 4.1. The new device targets infotainment, ADAS, telematics, domain controllers, and vehicle computers. Embedded UFS memory plays a critical role in enabling advanced automotive features by supporting quick data access, high throughput, and robust performance.

Kioxia says its 8th-generation BiCS Flash Technology drives improvements in efficiency and performance.

UFS supports full-duplex operation and efficient command queuing, which helps automotive systems respond quickly to data transfer requests. Kioxia says one of the key innovations of its embedded memory is that it incorporates Kioxia's 8th-generation BiCS Flash 3D memory technology. UFS 4.1 uses MIPI M-PHY version 5.0 and UniPro 2.0, enabling theoretical interface speeds of up to 23.2 Gbps per lane or 46.4 Gbps per device with two lanes.

Kioxia's BiCS Flash 3D Tech at Work in the UFS 4.1 Devices

Kioxia used CMOS‑Directly‑Bonded‑to‑Array (CBA) wafer bonding to develop this memory technology. This bonding technique fabricates logic circuitry and cell arrays separately under optimal conditions and vertically joins them together.

CBA wafer bonding technology. 

The cell array refers to the part of the NAND flash memory that physically stores the data. It consists of millions of individual memory cells, each capable of holding an electrical charge to represent bits: 1s and 0s. These cells are arranged in a grid-like structure, stacked vertically in 3D NAND, and grouped. This enables high‑temperature processing on the memory side without degrading the CMOS, boosting both performance and yield.

The new chips leverage an On‑Pitch Select‑Gate (OPS) layout, which removes unnecessary dummy strings to enhance density. Dummy strings refer to non-functional vertical columns of memory cells that are added to maintain physical symmetry and uniform layout in conventional NAND designs. These dummy strings don’t store data, but they take up space on the die and reduce overall memory density.

Memory Designed for Automotives and Data Centers

Kioxia claims such architectural advances deliver notably higher gigabyte density, faster I/O, and efficiency for operation in demanding environments like automotive systems and data centers. In these environments, memory must withstand sustained high throughput without overheating and maintain long-term reliability. Kioxia posits BiCS Flash as a solution to meet these demands without sacrificing efficiency or scalability.

Electron microscopy image of the 8th-generation BiCS Flash. 

The company also claims that its UFS 4.1 devices include enhanced diagnostic capabilities through a new vendor-specific health descriptor that provides deeper insight into the memory’s condition over time. This feature allows system designers and manufacturers to monitor the storage device's health more accurately, tracking factors like wear level, remaining lifespan, and usage patterns. In automotive and other mission-critical environments, these diagnostics help enable predictive maintenance, and systems can flag when storage is approaching failure conditions before it actually breaks down.

Another UFS 4.1 Memory Option

Kioxia is not the only company targeting UFS 4.1-compliant embedded memories. Companies like SK Hynix, for example, are highlighting thin packages for on-device AI with low power consumption and high read performance. SK Hynix has reduced its package thickness to 0.85 mm from previous generations, improving integration into ultra-slim devices. The company touts sequential read speeds up to 4,300 MB/s, with 15% faster random reads and 40% faster random writes. 

All images used courtesy of Kioxia.