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Electron-beam projector suits up for submicrometer race
World Abstracts on M icroelectronics and Reliability
911
the barrier height at the metal and semi-conductor contact, assuming that the dominant current is due to thermionic emission. When ion implantation is used to increase the barrier height, both thermionic emission and drift-diffusion of carriers become important in calculating the current. Numerical methods are used in solving Poisson's equation and the current continuity equations for an ion implanted doping profile. The electron and hole current in the surface region are calculated as a function of the total implantation dosage. The results show that the decrease of saturation current and the increase of effective barrier height in an ion implanted diode is mainly due to the suppression of the thermionic emission current by the implanted impurity atoms, rendering the diode to act like a pn junction.
A study of masking properties of SiO 2 and photoresists with boron ion implantation. JARM1LA CERVENA,VLADIMIR HNATOWICZ, JIRI HOFFMAN, JIR1 KV1TEK, PAVEL ONHEISER and VLADIMIRRYBKA. TESLA Electronics 1, 16 (1981). Using the ~°B (n, alpha) 7Li nuclear reaction induced by thermal neutrons, the masking properties of some materials were studied. The Rp and ARp values for l°B ions implanted at various energies ranging from 40 to 200 keV were determined in SiO 2 chemically or thermally grown and plasmatically deposited, as well as for Waycoat and KTRF photoresists.
Ion beam lithography. W. L. BROWN,T. VENKATESAN and A. WAGNER. Solid State Technology 60 (August 1981). The continuing miniaturization of integrated circuits has stimulated interest in new exposure techniques utilizing electrons, X-rays and ion beams. Ion beams offer ultimate advantages in sensitivity and fineness of feature size because of their penetration properties in materials. Lithographic patterns can be formed by use of finely focused scanning ion beams. Whole lithographic patterns can be transferred by ion optical imaging or by channeled ion lithography. The progress in both types of ion beam lithography and in the development of high brightness ion source and ion beam-compatible resists are summarized.
Electron beam writes next-generation IC patterns. R. MOORE, G. CACCOMA, H. PFEIFFER, E. WEBER and O. WOODWARD. Electronics 138 (3 November 1981). Variable spot shaping and subfield vector-writing techniques let beam write from 20 to 45 three-inch wafers per hour.
Electron-beam projector suits up for submicrometer race. RODNEY WARD. Electronics 142 (3 November 1981). Lithography machine can define chip features as small as 0.2 #m; system throughput can be as high as twenty-five 4 in. wafers an hour.
Etching SiO 2 in a reactive ion beam. BARBARA A. HEATH. Solid State Technology 75 (October 1981). Results of experiments directed toward selective etching of SiO 2 over Si using fluorocarbon ion beams are described. Highly anisotropic etching is demonstrated with a selectivity of 10:1 for SiO 2 over Si. Finally, reactive ion beam etching is compared with other dry etching methods.
911
the barrier height at the metal and semi-conductor contact, assuming that the dominant current is due to thermionic emission. When ion implantation is used to increase the barrier height, both thermionic emission and drift-diffusion of carriers become important in calculating the current. Numerical methods are used in solving Poisson's equation and the current continuity equations for an ion implanted doping profile. The electron and hole current in the surface region are calculated as a function of the total implantation dosage. The results show that the decrease of saturation current and the increase of effective barrier height in an ion implanted diode is mainly due to the suppression of the thermionic emission current by the implanted impurity atoms, rendering the diode to act like a pn junction.
A study of masking properties of SiO 2 and photoresists with boron ion implantation. JARM1LA CERVENA,VLADIMIR HNATOWICZ, JIRI HOFFMAN, JIR1 KV1TEK, PAVEL ONHEISER and VLADIMIRRYBKA. TESLA Electronics 1, 16 (1981). Using the ~°B (n, alpha) 7Li nuclear reaction induced by thermal neutrons, the masking properties of some materials were studied. The Rp and ARp values for l°B ions implanted at various energies ranging from 40 to 200 keV were determined in SiO 2 chemically or thermally grown and plasmatically deposited, as well as for Waycoat and KTRF photoresists.
Ion beam lithography. W. L. BROWN,T. VENKATESAN and A. WAGNER. Solid State Technology 60 (August 1981). The continuing miniaturization of integrated circuits has stimulated interest in new exposure techniques utilizing electrons, X-rays and ion beams. Ion beams offer ultimate advantages in sensitivity and fineness of feature size because of their penetration properties in materials. Lithographic patterns can be formed by use of finely focused scanning ion beams. Whole lithographic patterns can be transferred by ion optical imaging or by channeled ion lithography. The progress in both types of ion beam lithography and in the development of high brightness ion source and ion beam-compatible resists are summarized.
Electron beam writes next-generation IC patterns. R. MOORE, G. CACCOMA, H. PFEIFFER, E. WEBER and O. WOODWARD. Electronics 138 (3 November 1981). Variable spot shaping and subfield vector-writing techniques let beam write from 20 to 45 three-inch wafers per hour.
Electron-beam projector suits up for submicrometer race. RODNEY WARD. Electronics 142 (3 November 1981). Lithography machine can define chip features as small as 0.2 #m; system throughput can be as high as twenty-five 4 in. wafers an hour.
Etching SiO 2 in a reactive ion beam. BARBARA A. HEATH. Solid State Technology 75 (October 1981). Results of experiments directed toward selective etching of SiO 2 over Si using fluorocarbon ion beams are described. Highly anisotropic etching is demonstrated with a selectivity of 10:1 for SiO 2 over Si. Finally, reactive ion beam etching is compared with other dry etching methods.