NANOFABRICATION TOWARD SUB-10 NM AND ITS APPLICATION TO NOVEL NANODEVICES

The device feature size in Si ULSIs has been reduced over the years, and sooner or later we will probably enter the so-called nanoelectronics era. Two nanofabrication technologies, electron-beam lithography and atomic-beam holography, which are expected to play an important role in the coming era, are discussed first. In order to get finer patterns with electron-beam lithography, improvements in the characteristics of organic resists are crucially important. Organic negative resists with a fine resolution have been developed, and a high-quality resist line pattern with a width as small as 7 nm has been successfully formed. A new atom manipulation technique called atomic-beam holography has been proposed for nanofabrication. It enables direct pattern formation on a substrate by passing laser-cooled atoms through a computer-generated hologram. It is expected to be a technique with a fine resolution, reaching the atomic scale, and a high throughput. Nano-size devices are developed from two standpoints. One pursues the miniaturization limit of MOS transistors: in this context, we discuss the fabrication of MOS transistors with gate length down to 14 nm and their electrical characteristics. The other approach is to explore `breakthrough devices' that utilize quantum effects: single electron devices are one type of such devices. We discuss the operation of an all-metallic single-electron memory cell along with the electrical characteristics of a single-electron transistor made of aluminium.

[1]  Keith,et al.  Diffraction of atoms by a transmission grating. , 1988, Physical review letters.

[2]  Shinji Matsui,et al.  Ultrahigh resolution of calixarene negative resist in electron beam lithography , 1996 .

[3]  T. Sakamoto,et al.  Transistor operation of 30-nm gate-length EJ-MOSFETs , 1998, IEEE Electron Device Letters.

[4]  Bradley,et al.  Evidence of Bose-Einstein Condensation in an Atomic Gas with Attractive Interactions. , 1995, Physical review letters.

[5]  Takuma,et al.  Imaging and focusing of atoms by a fresnel zone plate. , 1991, Physical review letters.

[6]  Han,et al.  Measurement of single electron lifetimes in a multijunction trap. , 1994, Physical review letters.

[7]  C. Wieman,et al.  Observation of Bose-Einstein Condensation in a Dilute Atomic Vapor , 1995, Science.

[8]  W. Phillips,et al.  Laser Deceleration of an Atomic Beam , 1982 .

[9]  Yasunobu Nakamura,et al.  100-K Operation of Al-Based Single-Electron Transistors , 1996 .

[10]  Yasuo Takahashi,et al.  Fabrication technique for Si single-electron transistor operating at room temperature , 1995 .

[11]  T. Hänsch,et al.  Cooling of gases by laser radiation , 1975 .

[12]  Jaw-Shen Tsai,et al.  Aluminum single-electron nonvolatile floating gate memory cell , 1997 .

[13]  Chu,et al.  Trapping of neutral sodium atoms with radiation pressure. , 1987, Physical review letters.

[14]  D. Eigler,et al.  Positioning single atoms with a scanning tunnelling microscope , 1990, Nature.

[15]  Fujita,et al.  Holographic Manipulation of a Cold Atomic Beam. , 1996, Physical review letters.

[16]  S. Matsui,et al.  Manipulation of an atomic beam by a computer-generated hologram , 1996, Nature.

[17]  Shinji Matsui,et al.  Nanometer‐scale resolution of calixarene negative resist in electron beam lithography , 1996 .

[18]  K. B. Davis,et al.  Bose-Einstein Condensation in a Gas of Sodium Atoms , 1995, EQEC'96. 1996 European Quantum Electronic Conference.