摘要:

Isothermal annealing studies of boron implanted silicon have been made at temperatures above 600°C for boron doses in the range of 1014to 1015ions/cm2. A 5 eV activation energy is obtained in the temperaturè range 600°C to 900°C. This value is the same as that associated with the generation and subsequent migration of vacancies in silicon. This indicates that the mechanism responsible for the increase in electrical activity of the implanted boron is due to the thermal generation of vacancies and the diffusion of these vacancies or vacancy complexes to interstitial boron atoms, which then become substitutional.

ISSN:0033-7579    

DOI:10.1080/00337577108232558

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

Some methods have been recently developed to investigate the distribution of implanted ions in semiconductors, especially into silicon. Generally, these techniques are not valid for boron due to the absence of convenient radioactive isotopes, or to a too small sensitivity when the lower part of the distribution is of interest. This corresponds to our problem, since boron implanted nuclear particle detectors prepared with high resistivity material (up to 50,000 ω.cm) are needed. The properties of these P-N junctions depend in a certain amount on the impurity distribution existing several orders of magnitude below the top of the distribution. Therefore, only the junction location method can be employed. In this method a series ofN-type silicon samples, differing each from the other by an increase in resistivity are implanted with boron. The depth of theP-Njunction corresponds to the point of the profile where the concentrationNAis equal to that of the substrateND(i.e. this latter being well known from the resistivity of the starting material). If the location of the junction can be measured, the profile can then be constructed point by point. The junction location is visualized generally by copper staining. Roosild,(1)Kleinfelder,(2)Fairfield(3)and D. E. Davies(4)have used this procedure for boron implantations at energies higher than 50 keV. There is a problem due to the small penetration of the boron ion, and, for high resistivity materials, it is difficult to know the true limits of the zones stained with copper.

ISSN:0033-7579    

DOI:10.1080/00337577108232559

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

Outdiffusion, lattice location and electrical behavior of Zn, Cd, Hg and Se, Te implanted into silicon at 50 keV were investigated by backscattering and channeling effect of 1 MeV He+ions and by Hall effect and sheet resistivity measurements. All the species exhibited outdiffusion with thermal processing. A significant fraction of Zn, Cd and Hg, when implanted into a substrate of 350°C, occupied regular interstitial lattice sites, while 50–60 per cent of the Se and Te atoms were on substitutional lattice sites. Selenium implanted at room temperature and mercury implanted into a substrate of 350°C exhibited depth dependent lattice location. The implanted layers showedn-type behavior: the maximum value of number of carriers/cm2was less than the number of implanted ions/cm2in all cases. The highest electrical activity was observed for Se corresponding to 25 per cent of the substitutional component.

ISSN:0033-7579    

DOI:10.1080/00337577108232560

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

When the channeling-effect technique is used to determine the lattice location of an impurity which is not completely substitutional, quantitative interpretation of the results requires knowledge of the interaction yield between a channeled beam and an interstitial atom. We have investigated this problem for Yb implanted into silicon. Along the <110> direction, a peak of almost a factor of two is observed in backscattering yield from the Yb atoms, using a 1-MeV He beam. The height and angular width of the peak is satisfactorily interpreted in terms of flux-peaking of the channeled beam in the central region of the <110> channels.

ISSN:0033-7579    

DOI:10.1080/00337577108232561

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

Ion implantation allows controlled introduction of impurities into diamond. A basic problem is to determine if the implanted layers are dominated by substitutional doping or radiation damage effects. Optical and electrical measurements on the implanted diamonds revealed (1) a degradation of the band-gap and sample coloration, (2) no optical absorption levels which would be characteristic of hydrogenic ionization levels, (3) resistivity activation energies of 0.2 to 0.3 eV independent of the ion specie, and (4) no measurable Hall Effect.

ISSN:0033-7579    

DOI:10.1080/00337577108232562

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

This paper discusses the current state of ion-implantation as applied to MOS technology. It is shown how impurity doping by ion-implantation is used to produce self-aligned MOS gate structures. The reduction in circuit capacitance gives the designer a choice of higher switching speed or lower power dissipation. The availability of a linear resistor of value 1–10 kω/□ allows many new circuit techniques to be applied to monolithic circuits. This paper discusses ion-implantation technology, device design, and circuit performance. A number of implanted circuits are shown. Finally, improvements to the present technology which are still in the R & D phase are described.

ISSN:0033-7579    

DOI:10.1080/00337577108232563

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

Ion implantation of boron and phosphorus into silicon yields material that has electrical characteristics that are similar to silicon doped by conventional techniques. These results, and the ability to control and reproduce both the number of dopant atoms and their depth distribution, have been used to considerable advantage to fabricate both discrete devices and integrated circuits by ion implantation. We have made resistors, junction diodes, hyperabrupt diodes, IMPATTS, and field effect transistors. The narrow spread in the operating characteristics and the excellent performance of these devices, illustrate the advantages gained by using ion implantation as a step in the fabrication of devices.

ISSN:0033-7579    

DOI:10.1080/00337577108232564

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

The use of ion implantation to make integrated devices in silicon implies a good knowledge of the behavior of various parts of the device. This paper deals with three main topics: First the electrical characteristics of implanted diodes are described and their variations as a function of annealing temperature lead to a physical model taking into account the anisotropy of impurity concentration gradients. Second, experimental conditions before, during and after implantation are shown to have a strong influence on the quality of the final device, particularly on the value of the reverse leakage current. Third, effects of bombardment on silicon dioxide layers are studied. It is found that recovery of the layers is generally complete after a 300°C annealing.

ISSN:0033-7579    

DOI:10.1080/00337577108232565

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

Results are reported of measurements of the properties of diodes formed by ion implantation, and for comparison boron diffused P+N diodes of similar area close by on the same chip. The four group III acceptor impurities were implanted separately to a dose of 5 × 1015ions/cm2at room temperature into similar samples of suitably masked silicon. Boron ions were also implanted at liquid nitrogen temperature and 450°C. Annealing was limited to a maximum temperatare of 550 °C.

ISSN:0033-7579    

DOI:10.1080/00337577108232566

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor

摘要:

Sodium and nitrogen was implanted at 20 keV and 80 keV into MOS capacitors. The influence of the implantation on sodium ion drift was studied by temperature bias treatments combined with capacitance-voltage measurements. An ion trapping effect at the electrode is observed which is strongly enhanced by 20 keV implantations and the mobile ion content can be completely depleted by repeated drift treatments.

ISSN:0033-7579    

DOI:10.1080/00337577108232567

出版商:Taylor & Francis Group    

年代:1971

数据来源: Taylor