Controllable solid-state device comprising a tunnel barrier structure

Abstract

Abstract A controlled conductivity device includes a barrier structure (3) formed of regions of relatively conductive (11,13,11',13') and non-conductive material (10,12) such that in a first condition, charge carrier flow can occur through the structure and in a second condition the regions present a tunnel barrier configuration that inhibits charge carrier flow through the structure, an output region (2) to receive charge carriers that pass along a path through the structure, and an input region (6) for supplying charge carriers to the path so as to pass through the structure to the output region, wherein the regions of non-conductive material are configures so as to provide an energy band profile that comprises guard barrier components (14,16) adjacent the input and output regions respectively, and a main barrier component (15) between the guard barrier components, the main barrier component having a width (w') of 2nm or more, the guard barrier components having a width (w) of 3nm or less and the barriers being spaced apart by 45nm or less, or when the main barrier component has a width of 6nm or more, the barriers are spaced apart by 20nm or less. The device can be used as a memory in which case the output region (2) comprises a memory node to store charge, or as a transistor, in which case the input an output regions comprise a source and drain for charge carriers. A side gate (9) is provided to control current flow.

Inventors

• 👤 Hiroshi Mizuta
• 👤 Kazuo Nakazato
• 👤 Kiyoo Itoh
• 👤 Toshikazu Schimada
• 👤 Tatsuya Teshima
• 👤 Ken Yamaguchi

Bibliographic Details