Computer Devices Laboratory

/ Kazuyuki Saito / Professor
/ Kenichi Kuroda / Professor
/ Yasuhiro Hisada / Assistant Professor

The Computer Device Laboratory, the CDL, focuses on education and research on VLSI technology, devices, and their related area. The main activities are as follows:

1. Education:
   • Physics of Semiconductor Devices
   • Microelectronics: Analog and Digital Circuit Technology
   • VLSI Design: Device/Prcoess Design & VLSI architecture

2. Research: The main objective of the research in the CDL is to develop a new environment for VLSI design and diagnoses. That will be an intelligent manufacturing system for VLSIs including a statistical representation, a topographic representation, and an expert system representation of VLSI design and diagnoses. And the objects of representation are not restricted in the devices and processing technologies, but will cover from the manufacturing system modeling to the reliability of VLSI. The research projects being performed in the CDL are as follows:
   • Research on Parameter Extraction for VLSI Simulation; with NTT LSI Laboratories
   • Research on ULSI Design Education System; with universities
   • Research on the Precise Modeling for T-CAD; with two laboratories from NTT, companies, and universities
   • Optimization of Resources for VLSI Production; with a VLSI company at Aizu-Wakamatsu
   • The universal Test Boards for VLSI Packages; with a VLSI company at Aizu-Wakamatsu

Prof. Kazuyuki Saito: In these ten years, his research interest is going toward the computer integrated manufacturing system. His understanding of CIM is the Centralized Information Manufacturing. On this concept, he developed a novel VLSI yield modeling applying to the Yield Enhancement, a novel Topography Simulator, a Factory Modeling using Queuing System, a Local Area Network in the VLSI Factory and its Application on the Quality Enhancement of VLSI production. He is now developing a Production Scheduling System with a novel algorithm.

Prof. Kenichi Kuroda: Before joining this university, he has been engaged with the x-ray lithography project using a synchrotron radiation source at NTT. He keeps his interest in design of X-ray mirror system which is expected to be used for X-ray lithography in future ULSI production. He has been developing a useful optimizing tool for the mirror system design. After joining the CDL, he is also interested in the multiple-valued logic devices such as neuron MOS, quantum devices, and other devices. These devices are expected to solve the complexity crisis in future ULSI circuitry.

Prof. Yasuhiro Hisada: His interest is computer simulation of semiconductor crystal growth process. The quality and yield of LSI is influenced quality of semiconductor crystal. He is also interested in biometrics. Now, he has been developed measurement and analysis system of a living body signal. This research is related to research of LSI for signal processing and analog circuit and sensor. In addition, this research will become the base of ultimate interface between computer and human.

Refereed Journal Papers

1. Kazuyuki SAITO, Optimization of the Number of Machines and Operators Required for LSI Production. IEICE Trans. Electron, 1996, vol. E79-C, No. 8, p. 1112--1119.

   This paper concerns optimized facility design for VLSI production. The method proposed are applicable in planning LSI production facilities with a good balance between the number of machines and the number of operators. The sequence in each processing step is analyzed in detail. A new algorithm based on the queueing model is developed for simultaneous requirements for two kinds of resources, machines and operators. This estimation system can be applied to complicated fabrication schemes, such as batch processing, continuous processing, and mixed technologies. This methodology yields guidelines for ASIC LSI production system design.

2. Kazuyuki SAITO, Yoshiyuki SATO, Norikuni YABUMOTO and Yoshikazu HOMMA, Investigation of Defect Concentration in Implanted Silicon Substrates by Hydrogen Decoration. J. Electrochem. Soc., 1996. vol. 143, No. 12, p. 4101--4105.

   A new method for examining the damage profile in Si induced by arsenic implantation is proposed. In this method, hydrogen was used to decorate the damage, because broken bond defects formed during implantation preperentially adsorb hydrogen. The depth profile of defects was investigated using secondary ion mass spectroscopy by measuring the hydrogen intensity. Two dominant peaks were observed in the thermal desorption spectroscopy, whose intensity reflects the concentration of defects, and these were assigned to complexes of divacancies and self-interstitials and to simple broken bonds. The damages was distributed with almost constant concentration up to the amorphous-crystalline silicon boundary, but the observed profile differed from the theoretically expected profile. The cumulative concentrations of the two kinds of defects were examined by using two independent experimental procedures for the as-implanted substrate implanted with an arsenic with 2E15 cm$_{-2}$ at 30 keV. These were 1.3E13 cm$_{-2}$ for complex of divacancies and self-interstitials and 1.7E14 cm$_{-2}$ for the simple broken bonds.

1. K. Kuroda, K. Saito, and Y. Hisada. VLSI Technology Education using Process Simulator. Biwako Workshop for VLSI Education, 1996.

2. N. Yabumoto, Y. Sato, and K. Saito. Observation of Hydrogen trapped at the ion-implanted defects using TD-APIMS. Extended Abstracts for 19th Applied Physics Society Meeting, 1996.

1. Kazuyuki Saito, Research on Parameter Extraction for VLSI Simulation. Company Fund, NTT Research Fund, May 1996.

2. Kazuyuki Saito, Ken-ichi Kuroda, and Yasuhiro Hisada. Joint-Research on Development of A Novel Test Board, Fujitsu Tohoku Electronics, Dec. 1996 -.

3. Kazuyuki Saito, and Ken-ichi Kuroda, Joint-Research on Development of the Factory Simulation System. Fujitsu Tohoku Electronics, Dec. 1996 -.

4. Kenichi Kuroda, Research on Prototype VLSI Verification. Company Fund, May 1996.

1. Kazuyuki Saito, The Institute of Electronics, Information and Communication Engineers (IEICE) of Japan, Member of Board in Tohoku Chapter (from 1995.4 -- 1997.4).

2. Kazuyuki Saito, The Institute of Electrical Engineers of Japan, Member of Board in Tohoku Chapter, 1996.4--.

3. Kazuyuki Saito, Invited Talk for the Motolora Japan Co. on the Computer Integrated Manufacturing for VLSI Production, April 1996.

4. Kazuyuki Saito, Invited Talk for the Beijing Institute of Technology (BIT) on Computer Aided Design of VLSI and ASIC. Oct. 1996.

5. Kazuyuki Saito, Give a seminar on MOS VLSI Process Design for NTT Co. Sept. 1996.

6. Yasuhiro Hisada, Takahiro Ishida, Kenichi Kuroda, and Kazuyuki Saito. ACM97. Exhibition on CAI for VLSI Technology using Paradise-World, The VLSI Technology Education in the University of Aizu, March 1997.

7. Kazuyuki Saito, Invited Talk on "Ion Implantation Induced Defects for Intel Santa Clara. March 1997.

8. Ken Nakazawa, Hiromitsu Yano, Yasuhiro Hisada, Promotion of self awareness in a conditioning period of the national athletic swimming team - Application of an immediate feedback system of POMS(Profile Of Mood States) test using PC -. Univ. of AIZU, Center for Cultural Research and Studies Annual Review No. 3 1996. March 1997.

9. Ken Nakazawa, Yoshimasa Imamura, Yasuhiro Hisada, Observation of preparatory potential of arms action and timing of electric discharge of mascle. Univ. of AIZU, Center for Cultural Research and Studies Annual Review No.3 1996. March 1997.