- Email: [email protected]
Pinhole array capacitor for oxide integrity analysis
818
World Abstracts on Microelectronics and Reliability
Electron. 26 (10), 987 (1983). The important influence of the transition region on the interpretation of deep level impurity measurements is well established and these effects are usually evaluated numerically. A simple analytic expression is developed for the width of the non-steady state transition region which is shown to be in good agreement with the numerical results. It is also demonstrated that the expression is consistent with second order effects noted in experimental trap concentration measurements.
superlattice dispersion relations along the growth axis is dealt with. Several limiting cases and examples are discussed. The influence of the band non-parabolicity on the confinement energies in isolated q u a n t u m wells is emphasized. A brief discussion of impurity and exciton binding energies in q u a n t u m wells is presented. Finally the Stark effects on a q u a n t u m well are discussed.
A normalized analytical solution for the capacitance associated with uniformly doped semiconductors at equilibrium. R. P.
M. J. CALDAS and A. FAZZIO. Solid St. Commun. 49 (6), 537 (1984). The self-consistent field multiple-scattering X~ molecular cluster model is applied to calculate the electronic states of a divacancy plus two oxygen complex in silicon. The calculations were carried out for the undistorted configuration of the defect. The obtained results, which are in fairly good agreement with EPR measurements, confirm the main features of the accepted microscopic model for the Si P2 centre.
JINDAL. Solid-St. Electron. 26 (I0), 1005 (1983). A normalized solution for determining the capacitance associated with uniformly doped semiconductors at equilibrium is presented here. The present formulation allows the application of this solution to both the MIS surface problem as well as P N step junction problem under equilibrium conditions, subject to Boltzmann approximation. For the surface case the results are in normalized analytic form in agreement with previous analyses. For the junction case a better estimation of the depletion layer thickness results in an analytic expression which performs better than that based on the depletion approximation.
Reinterpretation of the silicon-hydrogen stretch frequencies in amorphous silicon. H. WAGNER and W. BEYER. Solid St. Commun. 48 (7), 585 (1983). The doublet structure of the infrared absorption in the silicon hydrogen stretch region for amorphous silicon is attributed mainly to environmental effects rather than to different Sill, (x = 1,2,3) groups. Infrared measurements are suited to discriminate between compact and porous amorphous material.
Size effect on different impurity levels in semiconductors. H. VAN CONG, S, BRUNET and J. C. MARTIN. Solid St. Commun. 49 (7), 697 (1984). The different impurity levels in crystals are investigated basing on a deformation potential model which is related to the impurity size effect. The donor levels such as Ed(O ) and Ea(Se) in lightly doped G a P are found to be equal to 898.55 and 103.00meV, respectively, in perfect agreement with the experimental results of Vink et al.
Pinhole array capacitor for oxide integrity analysis. M. G. BUEHLER, B. R. BLAES,C. A. PINA and T. W. GRISWOLD. Solid St. Technol. 131 (November 1983). The integrity of the metal-poly oxide and the gate oxide was evaluated for several 5-~tm CMOS-bulk processes. The pinhole array capacitor consists of diffused and poly fingers that form a network of M O S transistors (elements), which are capped by a deposited oxide and metal layer. The smallest structure used in this study contained about 15,000 elements and the largest structure contained about 68,000 elements. Each structure was divided into several subarrays. The structures are placed a number of times on each wafer. From a yield analysis of the subarrays, the elements per defect were found to be typically in excess of 50,000 elements/defect for the metal-poly oxide and 100,000 elements/defect for the gate oxide. From the switching behaviour of the transistors, the gate oxide defects were tentatively identified as gate-to-body shorts rather than gate-to-diffusion shorts.
Band structure, impurity levels and Stark effects in superlattices. G. BASTARD. Acta Electron. 25 (2), 147 (1983). In French. The superlattices are artificial semiconductors obtained by stacking alternatively layers of two semiconductors on top of each other. In this paper it is shown how the superlattice effect, i.e. the existence of an artificial periodicity superimposed to the natural one, can be described within the framework of a multi-band effective mass approximation (originally due to E. O. Kane). Charge transfer effects are not discussed (fiat band approximation). After recalling the main features of the Kane's model in bulk materials, the
Electronic structure calculations of V2q-O 2 complexes in silicon. VIVILI M. S. GOMES, LUCY V. C. ASSALI, J. R. LEITE,
Electrical properties of gallium arsenide ingots. S. MARTIN and G. JACOB. Acta Electron. 25 (2), 123 (1983). In French. The electrical properties of numerous gallium arsenide ingots are described. It is shown that, while the electrical properties of semi-insulating or P-type ingots are well accounted for by well-known models, the same does not hold for N-type ingots (10 ~5 10 ~6 cm - 3 ). From a close examination of several hypotheses, it appears that some inhomogeneously distributed native defects play a prominent part in the electrical properties of N-type ingots.
A study of grown-in impurities in silicon by deep-level transient spectroscopy. A. ROHATG1, J. R. DAVIS, R. H. HOPKINS and P. G. MCMULLIN. Solid-St. Electron. 26 (11), 1039 (1983). Deep levels due to various impurities incorporated into Czochralski silicon ingots during crystal growth have been delineated. The largest impurity-induced deep-level concentration, defined as the electrically active impurity concentration, is found to be a fraction of the metallurgical impurity content of the crystals. This fraction for a specific impurity depends on the thermal history of the sample and the ability of the impurity to diffuse. POCI 3 gettering of Ti and V produces a decreasing electrically active impurity concentration toward the surface of a silicon wafer, while there is no observable effect of this heat treatment on the Mo concentration. In the case of Cr, which diffuses much more rapidly than Mo, Ti, or V in silicon, a very significant reduction in the electrically active concentration is observed after heat treatment. Similarly, in metal-doped polysilicon wafers the electrically active Mo concentration appears unaffected by grain boundaries, but the electrically active Cr concentration at or near some grain boundaries is reduced by more than an order of magnitude compared to that at grain centres.
Thermal nitridation of silicon and silicon dioxide for thin gate insulators. Part I1. JUDITH A. NEMETZ and RICHARD E. TRESSLER. Solid St. Technol. 209 (September 1983). The thermal nitridation of silicon and silicon dioxide films in nitrogen and a m m o n i a to form thin nitride insulators for LSI and VLSI applications is a subject of much current interest. Although NH 3 nitridation produces nitride or oxynitride films more controllably than N z, the precise interrelationships between the composition of the nitridation ambient, the nitridation temperature and the composition and structure of the nitride film are not understood. A review of the properties of nitride films and the electrical characteristics of electronic devices incorporating them reveals the significant advantages of using nitride films as thin insulators compared to silicon dioxide. This review is being published in two parts. Part I was published in the February 1983 issue of Solid State Technology.
Semiconductor surface reconstruction. D. J. CHADI. Vacuum 33 (10-12), 613 (1983). A review of the current state of our
World Abstracts on Microelectronics and Reliability
Electron. 26 (10), 987 (1983). The important influence of the transition region on the interpretation of deep level impurity measurements is well established and these effects are usually evaluated numerically. A simple analytic expression is developed for the width of the non-steady state transition region which is shown to be in good agreement with the numerical results. It is also demonstrated that the expression is consistent with second order effects noted in experimental trap concentration measurements.
superlattice dispersion relations along the growth axis is dealt with. Several limiting cases and examples are discussed. The influence of the band non-parabolicity on the confinement energies in isolated q u a n t u m wells is emphasized. A brief discussion of impurity and exciton binding energies in q u a n t u m wells is presented. Finally the Stark effects on a q u a n t u m well are discussed.
A normalized analytical solution for the capacitance associated with uniformly doped semiconductors at equilibrium. R. P.
M. J. CALDAS and A. FAZZIO. Solid St. Commun. 49 (6), 537 (1984). The self-consistent field multiple-scattering X~ molecular cluster model is applied to calculate the electronic states of a divacancy plus two oxygen complex in silicon. The calculations were carried out for the undistorted configuration of the defect. The obtained results, which are in fairly good agreement with EPR measurements, confirm the main features of the accepted microscopic model for the Si P2 centre.
JINDAL. Solid-St. Electron. 26 (I0), 1005 (1983). A normalized solution for determining the capacitance associated with uniformly doped semiconductors at equilibrium is presented here. The present formulation allows the application of this solution to both the MIS surface problem as well as P N step junction problem under equilibrium conditions, subject to Boltzmann approximation. For the surface case the results are in normalized analytic form in agreement with previous analyses. For the junction case a better estimation of the depletion layer thickness results in an analytic expression which performs better than that based on the depletion approximation.
Reinterpretation of the silicon-hydrogen stretch frequencies in amorphous silicon. H. WAGNER and W. BEYER. Solid St. Commun. 48 (7), 585 (1983). The doublet structure of the infrared absorption in the silicon hydrogen stretch region for amorphous silicon is attributed mainly to environmental effects rather than to different Sill, (x = 1,2,3) groups. Infrared measurements are suited to discriminate between compact and porous amorphous material.
Size effect on different impurity levels in semiconductors. H. VAN CONG, S, BRUNET and J. C. MARTIN. Solid St. Commun. 49 (7), 697 (1984). The different impurity levels in crystals are investigated basing on a deformation potential model which is related to the impurity size effect. The donor levels such as Ed(O ) and Ea(Se) in lightly doped G a P are found to be equal to 898.55 and 103.00meV, respectively, in perfect agreement with the experimental results of Vink et al.
Pinhole array capacitor for oxide integrity analysis. M. G. BUEHLER, B. R. BLAES,C. A. PINA and T. W. GRISWOLD. Solid St. Technol. 131 (November 1983). The integrity of the metal-poly oxide and the gate oxide was evaluated for several 5-~tm CMOS-bulk processes. The pinhole array capacitor consists of diffused and poly fingers that form a network of M O S transistors (elements), which are capped by a deposited oxide and metal layer. The smallest structure used in this study contained about 15,000 elements and the largest structure contained about 68,000 elements. Each structure was divided into several subarrays. The structures are placed a number of times on each wafer. From a yield analysis of the subarrays, the elements per defect were found to be typically in excess of 50,000 elements/defect for the metal-poly oxide and 100,000 elements/defect for the gate oxide. From the switching behaviour of the transistors, the gate oxide defects were tentatively identified as gate-to-body shorts rather than gate-to-diffusion shorts.
Band structure, impurity levels and Stark effects in superlattices. G. BASTARD. Acta Electron. 25 (2), 147 (1983). In French. The superlattices are artificial semiconductors obtained by stacking alternatively layers of two semiconductors on top of each other. In this paper it is shown how the superlattice effect, i.e. the existence of an artificial periodicity superimposed to the natural one, can be described within the framework of a multi-band effective mass approximation (originally due to E. O. Kane). Charge transfer effects are not discussed (fiat band approximation). After recalling the main features of the Kane's model in bulk materials, the
Electronic structure calculations of V2q-O 2 complexes in silicon. VIVILI M. S. GOMES, LUCY V. C. ASSALI, J. R. LEITE,
Electrical properties of gallium arsenide ingots. S. MARTIN and G. JACOB. Acta Electron. 25 (2), 123 (1983). In French. The electrical properties of numerous gallium arsenide ingots are described. It is shown that, while the electrical properties of semi-insulating or P-type ingots are well accounted for by well-known models, the same does not hold for N-type ingots (10 ~5 10 ~6 cm - 3 ). From a close examination of several hypotheses, it appears that some inhomogeneously distributed native defects play a prominent part in the electrical properties of N-type ingots.
A study of grown-in impurities in silicon by deep-level transient spectroscopy. A. ROHATG1, J. R. DAVIS, R. H. HOPKINS and P. G. MCMULLIN. Solid-St. Electron. 26 (11), 1039 (1983). Deep levels due to various impurities incorporated into Czochralski silicon ingots during crystal growth have been delineated. The largest impurity-induced deep-level concentration, defined as the electrically active impurity concentration, is found to be a fraction of the metallurgical impurity content of the crystals. This fraction for a specific impurity depends on the thermal history of the sample and the ability of the impurity to diffuse. POCI 3 gettering of Ti and V produces a decreasing electrically active impurity concentration toward the surface of a silicon wafer, while there is no observable effect of this heat treatment on the Mo concentration. In the case of Cr, which diffuses much more rapidly than Mo, Ti, or V in silicon, a very significant reduction in the electrically active concentration is observed after heat treatment. Similarly, in metal-doped polysilicon wafers the electrically active Mo concentration appears unaffected by grain boundaries, but the electrically active Cr concentration at or near some grain boundaries is reduced by more than an order of magnitude compared to that at grain centres.
Thermal nitridation of silicon and silicon dioxide for thin gate insulators. Part I1. JUDITH A. NEMETZ and RICHARD E. TRESSLER. Solid St. Technol. 209 (September 1983). The thermal nitridation of silicon and silicon dioxide films in nitrogen and a m m o n i a to form thin nitride insulators for LSI and VLSI applications is a subject of much current interest. Although NH 3 nitridation produces nitride or oxynitride films more controllably than N z, the precise interrelationships between the composition of the nitridation ambient, the nitridation temperature and the composition and structure of the nitride film are not understood. A review of the properties of nitride films and the electrical characteristics of electronic devices incorporating them reveals the significant advantages of using nitride films as thin insulators compared to silicon dioxide. This review is being published in two parts. Part I was published in the February 1983 issue of Solid State Technology.
Semiconductor surface reconstruction. D. J. CHADI. Vacuum 33 (10-12), 613 (1983). A review of the current state of our