摘要:
A high-quality GaAs-type crystal thin film using an inexpensive Si wafer with good thermal release characteristics is achieved. Provided is a semiconductor wafer comprising an Si wafer; an inhibiting layer that is formed on the wafer and that inhibits crystal growth, the inhibiting layer including a covering region that covers a portion of the wafer and an open region that does not cover a portion of the wafer within the covering region; a Ge layer that is crystal-grown in the open region; and a functional layer that is crystal-grown on the Ge layer. The Ge layer may be formed by annealing with a temperature and duration that enables movement of crystal defects, and the annealing is repeated a plurality of times.
摘要:
A high-quality GaAs-type crystal thin film using an inexpensive Si wafer with good thermal release characteristics is achieved. Provided is a semiconductor wafer comprising a single-crystal Si wafer; an insulating layer that has an open region and that is formed on the wafer; a Ge layer that is epitaxially grown on the wafer in the open region; and a GaAs layer that is epitaxially grown on the Ge layer, wherein the Ge layer is formed by (i) placing the wafer in a CVD reaction chamber that can create an ultra-high vacuum low-pressure state, (ii) performing a first epitaxial growth at a first temperature at which raw material gas can thermally decompose, (iii) performing a second epitaxial growth at a second temperature that is higher than the first temperature, (iv) performing a first annealing, at a third temperature that is loss than a melting point of Ge, on epitaxial layers formed by the first and second epitaxial growths, and (v) performing a second annealing at a fourth temperature that is lower than the third temperature. The Ge layer may he formed by repeating the first annealing and the second annealing a plurality of times, and the insulating layer may be a silicon oxide layer.
摘要:
A high-quality GaAs-type crystal thin film using an inexpensive Si wafer with good thermal release characteristics is achieved. Provided is a semiconductor wafer comprising an Si wafer; a Ge layer that is crystal-grown on the wafer and shaped as an isolated island; and a functional layer that is crystal-grown on the Ge layer. The Ge layer may be shaped as an island having a size that docs not exceed double a distance moved by crystal defects as a result of annealing the Ge layer at a certain temperature for a certain time. The Ge layer may be shaped as an island having a size for which stress due to a difference relative to a thermal expansion coefficient of Si, which is material of the wafer, does not cause crystal dejects when the Ge layer is annealed at a certain temperature.
摘要:
A high-quality GaAs-type crystal thin film using an inexpensive Si wafer with good thermal release characteristics is achieved. Provided is a semiconductor wafer comprising an Si wafer; an inhibiting layer that is formed on the wafer and that inhibits crystal growth, the inhibiting layer including a covering region that covers a portion of the wafer and an open region that does not cover a portion of the wafer within the covering region; a Ge layer that is crystal-grown in the open region; and a functional layer that is crystal-grown on the Ge layer. The Ge layer may be formed by annealing with a temperature and duration that enables movement of crystal defects, and the annealing is repeated a plurality of times.
摘要:
In a method of determining the quality of a semiconductor epitaxial crystal wafer having a buffer structure portion comprised of epitaxial layers the semiconductor epitaxial crystal wafer (S) is irradiated with pulsed exciting light (5A) to modulate an internal electric field of the buffer structure portion, the electric transport properties deriving from the crystal quality of the buffer structure of the semiconductor epitaxial crystal wafer (S) are predicted based on a spectral difference in reflectance in reflection probe light (3B) from the semiconductor epitaxial crystal wafer (S), to determine the crystal quality of the buffer structure portion. The crystal quality may also be determined based on electric field strength calculated from Franz-Keldysh oscillation originating in the semiconductor chemical compound of the buffer structure portion.
摘要:
Disclosed is a mixed metal oxide comprising Na, M1, and M2, where M1 represents at least one element selected from the group consisting of Mg, Ca, Sr, and Ba; and M2 represents at least one element selected from the group consisting of Mn, Fe, Co, and Ni, wherein the molar ratio of Na:M1:M2 is a:b:1, where a is a value within the range of not less than 0.5 and less than 1; b is a value within the range of more than 0 and not more than 0.5; and “a+b” is a value within the range of more than 0.5 and not more than 1. An electrode having an active material containing the mixed metal oxide is also disclosed. Further disclosed is an electrode containing the electrode active material as well as a sodium secondary battery comprising the electrode as a positive electrode.
摘要:
An air battery containing an electrode and a polymer film, wherein the polymer film is disposed on the air intake side of the electrode, and the polymer film is a film of a polymer comprising a repeating unit represented by the following formula (1), wherein R1, R2, and m are defined in the specification.
摘要:
Disclosed is a sodium secondary battery. The sodium secondary battery comprises a first electrode and a second electrode comprising a carbonaceous material. The carbonaceous material satisfies one or more requirements selected from the group consisting of requirements 1, 2, 3 and 4. Requirement 1: R value (=ID/IG) obtained by Raman spectroscopic measurement is 1.07 to 3. Requirement 2: A value and σA value obtained by small angle X-ray scattering measurement are −0.5 to 0 and 0 to 0.010, respectively. Requirement 3: for an electrode comprising an electrode mixture obtained by mixing 85 parts by weight of the carbonaceous material with 15 parts by weight of poly(vinylidene fluoride), the carbonaceous material in the electrode after being doped and dedoped with sodium ions is substantially free from pores having a size of not less than 10 nm. Requirement 4: Q1 value obtained by a calorimetric differential thermal analysis is not more than 800 joules/g.
摘要:
The present invention provides a positive electrode active material that can suppress the necessity of performing sieving and is suitable for use in secondary batteries, particularly sodium secondary batteries. Also provided is a powder for a positive electrode active material as a raw material for the positive electrode active material. The powder for a positive electrode active material of the present invention comprises Mn-containing particles. In the cumulative particle size distribution on the volume basis of particles constituting the powder, D50, which is the particle diameter at a 50% cumulation measured from the smallest particle, is in the range of from 0.1 μm to 10 μm, and 90 vol % or more of the particles constituting the powder are in the range of from 0.3 times to 3 times D50. The powder for a positive electrode active material comprises Mn-containing particles, and 90 vol % or more of the particles constituting the powder are in the range of from 0.6 μm to 6 μm. The positive electrode active material is a powdery positive electrode active material obtained by calcining a mixture of the powder for positive electrode active material and a sodium compound. The positive electrode for sodium rechargeable batteries comprises the positive electrode active material.
摘要:
Disclosed is a sodium secondary battery. The sodium secondary battery comprises a first electrode and a second electrode comprising a carbonaceous material. The carbonaceous material satisfies one or more requirements selected from the group consisting of requirements 1, 2, 3 and 4. Requirement 1: R value (=ID/IG) obtained by Raman spectroscopic measurement is 1.07 to 3. Requirement 2: A value and σA value obtained by small angle X-ray scattering measurement are −0.5 to 0 and 0 to 0.010, respectively. Requirement 3: for an electrode comprising an electrode mixture obtained by mixing 85 parts by weight of the carbonaceous material with 15 parts by weight of poly(vinylidene fluoride), the carbonaceous material in the electrode after being doped and dedoped with sodium ions is substantially free from pores having a size of not less than 10 nm. Requirement 4: Q1 value obtained by a calorimetric differential thermal analysis is not more than 800 joules/g.