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Preparation and evaluation of epitaxial silicon films prepared by vacuum evaporation
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A B S T R A C T S ON . M I C R O E L E C T R O N I C S A N D R E L I A B I L I T Y
The effect of dislocations on diffusion in g e r m a n i u m . * L. A. [-IELDr and J. N. HOBSTETTER. .-tcta 3[etallum, ica (U.S.A.) 11, It) (1963), pp. 1165-1168. The diffusivitv of antimony has been measured in specially deformed germanium specimens: (1) parallel to a high density array of parallel edge dislocations, (2) perpendicular to this array, and (3) in low dislocation, non-deiormed material. The diffusivitv of indium was measured in heavily deformed and in non-deformed germanium specimens. The results of these experiments indicate that the array of parallel dislocations in densities of between 10~ and 10 r cm-: has no effect upon the diffusion of antimony m p-type germanium. Similarly, the introduction of high densities of dislocations has no measurable effect upon the diffusion of indium into n-type germanium. Interaction b e t w e e n oxygen and a l u m i n i u m in germanium.*\V. D. EDWARI>5,J..4ppl. Phys. (U.S.A.) 34, 2 (I963), pp. 2497-2498. Successive additions of AI, O,-rod AI--(), to~ether were madc to the ftlrnace during the gro~th of a crystal. These experiments slyowed that :{l--O, in germanium forms an eIectricalIy inactive neutral complex. No similar reaction seems to arise between oxygen and Sb, In, B, or Bi in germanium. This type of reaction is useful in rendering dopants inactive. A paramagnetic species in irradiated (NH,)._,HPOa. J. R. MORTOX, .7. Phys. Chem. Solids 24 (1963), pp. 209-212. An oriented paramagnetic fragment has been detected in single crystals of (NH~)2HPOt ~,-irradiated at 300'K. The E.P.R. spectra of the species are characteristic of a r:-electron radical centred on a nitrogen atom. The fragment is of the fornl [-[--N.~, its orientation in the lattice probably bein~ determined by very weak hydrogen bonds to a phosphate ion. Reflectivity of heavily doped p and n-type silicon at the 3-4 eV and 4.5 eV peak. B. R. BI<.X.MER, G.VERrOGEN and P. PKN.xI.',G, Solid State Communications 1 (1963), pp. 138-143. The absolute reflectivitv of a series of p and n-type silicon crystals has been measured in the region from 3.4 e\" to 5"3 eV. The energies of two maxima in reflcctivity did not shift for impurity concentrations up to 10~"/cn ~ No essential difference has been found between ;; andp-type samples. The 3-4 eV peak is showinq a growing asymmetry at higher concentrations. The maximum in reflectivitv in the 4'3 eV peak occurs at 4-545 0-02 eV. THIN FILM INTEGRATED CIRCUITS Preparation and evaluation of epitaxial silicon films prepared by v a c u u m evaporation. A. P. 1tALE, ~'acuum 13, 3 (1963), pp. 93-100. Single crystal films of both types have been deposited in :t high (10 -~ lorry vacuum system. Electron beam heating, as well as resistive heating, were used to heat the sources. Low energy argon ion bombardment and thermal etching were used to clean the surfaces of the substrates. T h e investigated temperature range of the substrates was 1000-1300:C. Single crystal fihns by back reflection X-ray were obtained when the substrates were above 1125:C (1400°K), which is about 0"8 of the melting point (1700:K). Fast deposition rates (21--1 ~./min) gave the best films. Diodes and transistors were prepared from some of these films to obtain an indication of the p-n junction and interface perfection. The p-n junctions showed higher reverse leakage and thus less perfection than that observed with devices in crystals grown by the Czochratski method. N e w approach to thin films. A. E. L~:SSOR, CEC/Recordings 17, 1 (1963), pp. 4 7 . Film circuits, in particular resistive-capacitive-networks, have reached a state of development where their large-scale application has become feasible. One of the first semi-automated systems scaled for mass production has been built by IBM's Components Division. Developed for the Naval Avionics Facility at Indianapolls, the prototype combines deposition equipment, controls and monitors into an integrated system. High frequency surface varactors. A. E. FEUERSANGERand D. R. Faa.xKr~, Trans. IEEE ED-10, 3 (1963), p. 143. Experimental surface varactors constructed from germanium and silicon, with titanium dioxide films as a dielectric, are described. Measurements have been made to determine their behaviour at frequencies up to 9 kMc. The capacitance ratio and specific capacitance change are in good agreement with the theory of surface varactors. The feasibility of high-frequency operation of this device is demonstrated on epi{axial-silicon surface varactors with zero-bias cut-off frequencies above 1000 kMc. From the analysis of the series resistance in practical structures, cutoff frequencies in the Teracycle range appear possible.
A B S T R A C T S ON . M I C R O E L E C T R O N I C S A N D R E L I A B I L I T Y
The effect of dislocations on diffusion in g e r m a n i u m . * L. A. [-IELDr and J. N. HOBSTETTER. .-tcta 3[etallum, ica (U.S.A.) 11, It) (1963), pp. 1165-1168. The diffusivitv of antimony has been measured in specially deformed germanium specimens: (1) parallel to a high density array of parallel edge dislocations, (2) perpendicular to this array, and (3) in low dislocation, non-deiormed material. The diffusivitv of indium was measured in heavily deformed and in non-deformed germanium specimens. The results of these experiments indicate that the array of parallel dislocations in densities of between 10~ and 10 r cm-: has no effect upon the diffusion of antimony m p-type germanium. Similarly, the introduction of high densities of dislocations has no measurable effect upon the diffusion of indium into n-type germanium. Interaction b e t w e e n oxygen and a l u m i n i u m in germanium.*\V. D. EDWARI>5,J..4ppl. Phys. (U.S.A.) 34, 2 (I963), pp. 2497-2498. Successive additions of AI, O,-rod AI--(), to~ether were madc to the ftlrnace during the gro~th of a crystal. These experiments slyowed that :{l--O, in germanium forms an eIectricalIy inactive neutral complex. No similar reaction seems to arise between oxygen and Sb, In, B, or Bi in germanium. This type of reaction is useful in rendering dopants inactive. A paramagnetic species in irradiated (NH,)._,HPOa. J. R. MORTOX, .7. Phys. Chem. Solids 24 (1963), pp. 209-212. An oriented paramagnetic fragment has been detected in single crystals of (NH~)2HPOt ~,-irradiated at 300'K. The E.P.R. spectra of the species are characteristic of a r:-electron radical centred on a nitrogen atom. The fragment is of the fornl [-[--N.~, its orientation in the lattice probably bein~ determined by very weak hydrogen bonds to a phosphate ion. Reflectivity of heavily doped p and n-type silicon at the 3-4 eV and 4.5 eV peak. B. R. BI<.X.MER, G.VERrOGEN and P. PKN.xI.',G, Solid State Communications 1 (1963), pp. 138-143. The absolute reflectivitv of a series of p and n-type silicon crystals has been measured in the region from 3.4 e\" to 5"3 eV. The energies of two maxima in reflcctivity did not shift for impurity concentrations up to 10~"/cn ~ No essential difference has been found between ;; andp-type samples. The 3-4 eV peak is showinq a growing asymmetry at higher concentrations. The maximum in reflectivitv in the 4'3 eV peak occurs at 4-545 0-02 eV. THIN FILM INTEGRATED CIRCUITS Preparation and evaluation of epitaxial silicon films prepared by v a c u u m evaporation. A. P. 1tALE, ~'acuum 13, 3 (1963), pp. 93-100. Single crystal films of both types have been deposited in :t high (10 -~ lorry vacuum system. Electron beam heating, as well as resistive heating, were used to heat the sources. Low energy argon ion bombardment and thermal etching were used to clean the surfaces of the substrates. T h e investigated temperature range of the substrates was 1000-1300:C. Single crystal fihns by back reflection X-ray were obtained when the substrates were above 1125:C (1400°K), which is about 0"8 of the melting point (1700:K). Fast deposition rates (21--1 ~./min) gave the best films. Diodes and transistors were prepared from some of these films to obtain an indication of the p-n junction and interface perfection. The p-n junctions showed higher reverse leakage and thus less perfection than that observed with devices in crystals grown by the Czochratski method. N e w approach to thin films. A. E. L~:SSOR, CEC/Recordings 17, 1 (1963), pp. 4 7 . Film circuits, in particular resistive-capacitive-networks, have reached a state of development where their large-scale application has become feasible. One of the first semi-automated systems scaled for mass production has been built by IBM's Components Division. Developed for the Naval Avionics Facility at Indianapolls, the prototype combines deposition equipment, controls and monitors into an integrated system. High frequency surface varactors. A. E. FEUERSANGERand D. R. Faa.xKr~, Trans. IEEE ED-10, 3 (1963), p. 143. Experimental surface varactors constructed from germanium and silicon, with titanium dioxide films as a dielectric, are described. Measurements have been made to determine their behaviour at frequencies up to 9 kMc. The capacitance ratio and specific capacitance change are in good agreement with the theory of surface varactors. The feasibility of high-frequency operation of this device is demonstrated on epi{axial-silicon surface varactors with zero-bias cut-off frequencies above 1000 kMc. From the analysis of the series resistance in practical structures, cutoff frequencies in the Teracycle range appear possible.