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Double space charge injection in solids
268
ABSTRACTS
ON
ELECTRONICS
RELIABILITY
AND
MICROMINIATURIZATION
Parasitics in integrated circuits. H. K. DICKEN, Electronics, p. 32 (July 5, 1963). The design of fully integrated circuits is going to be more complex than circuit design using conventional components. Isolation problems can be solved by adding extra p-n junctions, but at the expense of introducing extraneous diodes, capacitors and transistors. The etching processes in germanium pnJunctions. M. BERTOLOTTI, V. GRASSO, T. PAPA and D. SETTE, AZta Frequenzu 32, No. 1, 13-20 (1963). The etching processes in germanium pn-junctions have been studied through metallographic inspection of commercial transistors. The following etches have been tested: CP_,, CP-,A, H,O,, HNO,, diluted HNO,, Cu(NO,),. Time progressing of the etching action has been followed on and temperature effects have been observed for the various etches. Special attention has been given to the formation of steps in the transition region between n and p zones. Temperature coefficient of resistance of the high pressure phases of Si, Ge and some III-V and II-VI compounds. S. MINOMURA, G. A. SAMARA and A. G. DRICKAMER, J. Appl. Phys. (Nov. 1962). The high pressure phases of all compounds studied which had a zinc blende structure were metallic. Data is given on CdSe relating resistance, temperature and pressure. The high pressure phase of CdS is a semiconductor. Double space charge injection in solids. G. A. Cox and R. H. ‘~‘REDGOLD,Whys. Letters, pp. 199-200 (April 1, 1963). An attempt has been made to obtain a completely unambiguous demonstration of double injection using BaTiO, single crystals at a temperature substantially above the Curie point. Ordinary thermal injection of electrons at the cathode and optical injection of holes at the anode was used. BaTiO, plates about 0.1 mm thick were employed, and the electrodes were evaporated on at 1O-e torr. Using light in a narrow band centred around 3725 A, illumination through the cathode led to no detectable increase of current above the “dark” value. Illumination through the anode produced a current about 30 times larger than the dark current. The current was strongly dependent on temperature. It is evident from the results that the light creates holes at the anode. It will also create electrons at the cathode when that electrode is illuminated but, for the injecting contact postulated there will already be a high density of electrons in the conduction band at the cathode and the current is limited by the diffusion field not by the lack of available carriers at the electrode. The temperature dependence of the current is explained by supposing that the electron and hole currents interact by virtue of their associated charges. On the electronic conduction of Or-Sic crystals between 300 and 1500°K. H. J. VAN DALL, W. F. KNIPPENBERG and J. D. WASSCHER, J. Whys. Chem. Solids pp. 109-127 (Jan. 1963). The Hall Constant and the conductivity of lamellar hexagonal SIC crystals were measured in a temperature range from 77” to 1500°K. Measurements were carried out in a plane perpendicular to the hexagonal c-axis using van der Pauw’s method. Most crystals were p-type conducting. Grown by the Lely method and purposely doped during growth, the dominating impurities detected were Al, B and Cl. The Hall data in the temperature range 300°K to 1300°K were analysed. An acceptor level of 0.27eV above the valence band could be related to Al. Another level at 0.39eV was found, but could not be identified. It appeared that chlorine has no effect on the electric conduction. An analysis of the dependence of the mobility of holes and electrons is given in terms of optical, acoustical, piezoelectric and impurity scattering. The technique of solid state circuits.* J. WALKER, Schweitz. tech. Z(STZ) 59, No. 41, p. 797 (Oct. 1962). (In German.) Steps in miniaturization are described and the present methods of forming active and passive circuit elements on Si are reviewed. Linear and non-linear circuits are discussed. Junction formation in silicon by positive ion bombardment. R. R. FERBER, Trans. I.E.E.E. NS-10, No. 2, p. 15 (April 1963). The effects of silicon bombardment by hydrogen, nitrogen, oxygen, neon, xenon, phosphorus and boron ions have been studied using a Van de Graaff accelerator and a 250 KV Cockroft-Walton accelerator to produce ions with energies ranging from 50 keV to 1 MeV. Bombardments with each of the gaseous ions produced type conversion in p type silicon. ‘The n type + Based on Electrical
Engineering
Abstracts
by kind permission
of The
Institution
of Electrical
Engineers.
ABSTRACTS
ON
ELECTRONICS
RELIABILITY
AND
MICROMINIATURIZATION
Parasitics in integrated circuits. H. K. DICKEN, Electronics, p. 32 (July 5, 1963). The design of fully integrated circuits is going to be more complex than circuit design using conventional components. Isolation problems can be solved by adding extra p-n junctions, but at the expense of introducing extraneous diodes, capacitors and transistors. The etching processes in germanium pnJunctions. M. BERTOLOTTI, V. GRASSO, T. PAPA and D. SETTE, AZta Frequenzu 32, No. 1, 13-20 (1963). The etching processes in germanium pn-junctions have been studied through metallographic inspection of commercial transistors. The following etches have been tested: CP_,, CP-,A, H,O,, HNO,, diluted HNO,, Cu(NO,),. Time progressing of the etching action has been followed on and temperature effects have been observed for the various etches. Special attention has been given to the formation of steps in the transition region between n and p zones. Temperature coefficient of resistance of the high pressure phases of Si, Ge and some III-V and II-VI compounds. S. MINOMURA, G. A. SAMARA and A. G. DRICKAMER, J. Appl. Phys. (Nov. 1962). The high pressure phases of all compounds studied which had a zinc blende structure were metallic. Data is given on CdSe relating resistance, temperature and pressure. The high pressure phase of CdS is a semiconductor. Double space charge injection in solids. G. A. Cox and R. H. ‘~‘REDGOLD,Whys. Letters, pp. 199-200 (April 1, 1963). An attempt has been made to obtain a completely unambiguous demonstration of double injection using BaTiO, single crystals at a temperature substantially above the Curie point. Ordinary thermal injection of electrons at the cathode and optical injection of holes at the anode was used. BaTiO, plates about 0.1 mm thick were employed, and the electrodes were evaporated on at 1O-e torr. Using light in a narrow band centred around 3725 A, illumination through the cathode led to no detectable increase of current above the “dark” value. Illumination through the anode produced a current about 30 times larger than the dark current. The current was strongly dependent on temperature. It is evident from the results that the light creates holes at the anode. It will also create electrons at the cathode when that electrode is illuminated but, for the injecting contact postulated there will already be a high density of electrons in the conduction band at the cathode and the current is limited by the diffusion field not by the lack of available carriers at the electrode. The temperature dependence of the current is explained by supposing that the electron and hole currents interact by virtue of their associated charges. On the electronic conduction of Or-Sic crystals between 300 and 1500°K. H. J. VAN DALL, W. F. KNIPPENBERG and J. D. WASSCHER, J. Whys. Chem. Solids pp. 109-127 (Jan. 1963). The Hall Constant and the conductivity of lamellar hexagonal SIC crystals were measured in a temperature range from 77” to 1500°K. Measurements were carried out in a plane perpendicular to the hexagonal c-axis using van der Pauw’s method. Most crystals were p-type conducting. Grown by the Lely method and purposely doped during growth, the dominating impurities detected were Al, B and Cl. The Hall data in the temperature range 300°K to 1300°K were analysed. An acceptor level of 0.27eV above the valence band could be related to Al. Another level at 0.39eV was found, but could not be identified. It appeared that chlorine has no effect on the electric conduction. An analysis of the dependence of the mobility of holes and electrons is given in terms of optical, acoustical, piezoelectric and impurity scattering. The technique of solid state circuits.* J. WALKER, Schweitz. tech. Z(STZ) 59, No. 41, p. 797 (Oct. 1962). (In German.) Steps in miniaturization are described and the present methods of forming active and passive circuit elements on Si are reviewed. Linear and non-linear circuits are discussed. Junction formation in silicon by positive ion bombardment. R. R. FERBER, Trans. I.E.E.E. NS-10, No. 2, p. 15 (April 1963). The effects of silicon bombardment by hydrogen, nitrogen, oxygen, neon, xenon, phosphorus and boron ions have been studied using a Van de Graaff accelerator and a 250 KV Cockroft-Walton accelerator to produce ions with energies ranging from 50 keV to 1 MeV. Bombardments with each of the gaseous ions produced type conversion in p type silicon. ‘The n type + Based on Electrical
Engineering
Abstracts
by kind permission
of The
Institution
of Electrical
Engineers.