The final report is made on the fabrication of MOS transistors by ion implantation. Two different n-channel depletion mode MOS transistors were fabricated. These transistors are to be used to compare surface states of the ion implanted units with surface states of conventional diffused devices. (Author).

In recent years great progress has been made in the field of ion implantation, particularly with respect to applications in semiconductors. It would be impos sible not to note the growing interest in this field, both by research groups and those directly concerned with production of devices. Furthermore, as several papers have pointed out, ion implantation and its associated technologies promise exciting advances in the development of new kinds of devices and provide power ful new tools for materials investigations. It was, therefore, appropriate to arrange the II. International Conference on Ion Implantation in Semiconductors within the rather short time of one year since the first conference was held in 1970 in Thousand Oaks, California. Although ori ginally planned on a small scale with a very limited number of participants, more than two hundred scientists from 15 countries participated in the Conference which was held May 24 - 28, 1971 at the Congress Center in Garmisch-Partenkirchen. This volume contains the papers that were presented at the Conference. Due to the tremendous volume of research presented, publication here of all the works in full detail was not possible. Many authors therefore graciously agreed to submit abbreviated versions of their papers.

The technique of ion implantation has become a very useful and stable technique in the field of semiconductor device fabrication. This use of ion implantation is being adopted by industry. Another important application is the fundamental study of the physical properties of materials. The First Conference on Ion Implantation in Semiconductors was held at Thousand Oaks, California in 1970. The second conference in this series was held at Garmish-Partenkirchen, Germany, in 1971. At the third conference, which convened at Yorktown Heights, New York in 1973, the emphasis was broadened to include metals and insulators as well as semiconductors. This scope of the conference was still accepted at the fourth conference which was held at Osaka, Japan, in 1974. A huge number of papers had been submitted to this conference. All papers which were presented at the Fourth International Conference on Ion Implantation in Semiconductors and Other Materials are included in this proceedings. The success of this conference was due to technical presentations and discussions of 224 participants from 14 countries as well as to financial support from many companies in Japan. On behalf of the committee, I wish to thank the authors for their excellent papers and the sponsors for their financial support. The International Committee responsible for advising this conference consisted of B.L. Crowder, J.A. Davies, G. Dearna1ey, F.H. Eisen, Ph. G1otin, T. Itoh, A.U. MacRae, J.W. Mayer, S. Namba, I. Ruge, and F.L. Vook.

Ion implantation offers one of the best examples of a topic that starting from the basic research level has reached the high technology level within the framework of microelectronics. As the major or the unique procedure to selectively dope semiconductor materials for device fabrication, ion implantation takes advantage of the tremendous development of microelectronics and it evolves in a multidisciplinary frame. Physicists, chemists, materials sci entists, processing, device production, device design and ion beam engineers are all involved in this subject. The present monography deals with several aspects of ion implantation. The first chapter covers basic information on the physics of devices together with a brief description of the main trends in the field. The second chapter is devoted to ion im planters, including also high energy apparatus and a description of wafer charging and contaminants. Yield is a quite relevant is sue in the industrial surrounding and must be also discussed in the academic ambient. The slowing down of ions is treated in the third chapter both analytically and by numerical simulation meth ods. Channeling implants are described in some details in view of their relevance at the zero degree implants and of the available industrial parallel beam systems. Damage and its annealing are the key processes in ion implantation. Chapter four and five are dedicated to this extremely important subject.

Ion implantation technology has made a major contribution to the dramatic advances in integrated circuit technology since the early 1970's. The ever-present need for accurate models in ion implanted species will become absolutely vital in the future due to shrinking feature sizes. Successful wide application of ion implantation, as well as exploitation of newly identified opportunities, will require the development of comprehensive implant models. The 141 papers (including 24 invited papers) in this volume address the most recent developments in this field. New structures and possible approaches are described. The implications for ion implantation technology as well as additional observations of needs and opportunities are discussed. The volume will be of value to all those who are interested in acquiring a more complete understanding of the current developments in ion implantation processes and comprehensive implant models.

Complementary MOS transistor (CMOST) circuits offer great potential for very low power operation. These circuits are analyzed to determine their ultimate obtainable performance, and fabrication techniques are developed that produce circuits with the lowest power-speed product reported to date. The MOST is treated as a distributed nonlinear transmission line to investigate the detailed nature of its transient response. These methods are applied to the analysis of the switching performance of CMOST logic gates. This analysis predicts that power consumption has no lower bound if the gate can be operated at low voltages and if the transistors are small enough. A new MOST model is developed that describes effects that become significant at small voltages and sizes. A method for adjusting MOST threshold voltage by ion implantation is described.

The aim of these proceedings is to present and stimulate discussion on the many subjects related to ion implantation among a broad mix of specialists from areas as diverse as materials science, device production and advanced ion implanters.The contents open with a paper on the future developments of the microelectronics industry in Europe within the framework of the global competition. The subsequent invited and oral presentations cover in detail the following areas: trends in processing and devices, ion-solid interaction, materials science issues, advanced implanter systms, process control and yield, future trends and applications.