Ferroelectric MirrorBit-Integrated Field-Programmable Memory Array for TCAM, Storage, and In-Memory Computing Applications

TL;DR

This paper introduces a reconfigurable ferroelectric MirrorBit memory array that combines multi-state storage, fast operation, and reconfigurability for efficient in-memory and associative computing applications.

Contribution

It presents a novel ferroelectric MirrorBit-based memory architecture with multi-state capability and reconfigurability, enabling versatile in-memory computing functions.

Findings

Demonstrated 4-state (2-bit) memory using polarization gradients.

Showed reconfigurable array switching between AND and NOR logic modes.

Enabled fast write, dense storage, and efficient search in a unified architecture.

Abstract

In-memory computing on a reconfigurable architecture is the emerging field which performs an application-based resource allocation for computational efficiency and energy optimization. In this work, we propose a Ferroelectric MirrorBit-integrated field-programmable reconfigurable memory. We show the conventional 1-Bit FeFET, the MirrorBit, and MirrorBit-based Ternary Content-addressable memory (MCAM or MirrorBit-based TCAM) within the same field-programmable array. Apart from the conventional uniform Up and Down polarization states, the additional states in the MirrorBit are programmed by applying a non-uniform electric field along the transverse direction, which produces a gradient in the polarization and the conduction band energy. This creates two additional states, thereby, creating a total of 4 states or 2-bit of information. The gradient in the conduction band resembles a Schottky barrier (Schottky diode), whose orientation can be configured by applying an appropriate field. The TCAM operation is demonstrated using the MirrorBit-based diode on the reconfigurable array. The reconfigurable array architecture can switch from AND-type to NOR-type and vice-versa. The AND-type array is appropriate for programming the conventional bit and the MirrorBit. The MirrorBit-based Schottky diode in the NOR-array resembles a crossbar structure, which is appropriate for diode-based CAM operation. Our proposed memory system can enable fast write via 1-bit FeFET, the dense data storage capability by Mirror-bit technology and the fast search capability of the MCAM. Further, the dual configurability enables power, area and speed optimization making the reconfigurable Fe-Mirrorbit memory a compelling solution for In-memory and associative computing.