Abstract:
Provided is a method of manufacturing a nitride system III-V compound layer which improves the quality and facilitates the manufacturing process and a method of manufacturing a substrate employing the method of manufacturing a nitride system III-V compound layer. A first growth layer (31) is grown on a growth base (10) at a growth rate, in a vertical direction to the growth surface, higher than 10 mu m/h. Subsequently, a second growth layer (32) is grown at a growth rate, in a vertical direction to the growth surface, lower than 10 mu m/h. The first growth layer (31) grown at the higher growth rate has a rough surface. However, the second growth layer (32) is grown at the lower growth rate than that used for growing the first growth layer (31), so that depressions of the surface of the first growth layer (31) are filled and thus the surface of the second growth layer (32) is flattened. Further, growth takes place laterally so as to fill the depressions of the surface of the first growth layer (31). Thus, dislocation extending from the first growth layer (31) bends laterally and density of dislocation propagating to the surface of the second growth layer (32) is greatly lowered.
Abstract:
A method for growing nitride III-V compound semiconductor layers, comprises the steps of: growing a first BwAlxGayInzN layer (where 0≤w≤1, 0≤x≤1, 0≤y≤1, 0≤z≤1 and w+x+y+z=1) on a substrate by first vapor deposition at a growth rate not higher than 4 mu m/h; and growing a second BwAlxGayInzN layer (where 0≤w≤1, 0≤x≤1, 0≤y≤1, 0≤z≤1 and w+x+y+z=1) on the first BwAlxGayInzN layer by second vapor deposition at a growth rate higher than 4 mu m/h and not higher than 200 mu m/h. A method for fabricating a nitride III-V compound semiconductor substrate, comprises the steps of: growing a first BwAlxGayInzN layer (where 0≤w≤1, 0≤x≤1, 0≤y≤1, 0≤z≤1 and w+x+y+z=1) on a substrate by first vapor deposition at a growth rate not higher than 4 mu m/h; growing a second BwAlxGayInzN layer (where 0≤w≤1, 0≤x≤1, 0≤y≤1, 0≤y≤1 and w+x+y+z=1) on the first BwAlxGayInzN layer by second vapor deposition at a growth rate higher than 4 mu m/h and not higher than 200 mu m/h; and removing the substrate.
Abstract:
Provided is a method of manufacturing a nitride system III-V compound layer which improves the quality and facilitates the manufacturing process and a method of manufacturing a substrate employing the method of manufacturing a nitride system III-V compound layer. A first growth layer (31) is grown on a growth base (10) at a growth rate, in a vertical direction to the growth surface, higher than 10 mu m/h. Subsequently, a second growth layer (32) is grown at a growth rate, in a vertical direction to the growth surface, lower than 10 mu m/h. The first growth layer (31) grown at the higher growth rate has a rough surface. However, the second growth layer (32) is grown at the lower growth rate than that used for growing the first growth layer (31), so that depressions of the surface of the first growth layer (31) are filled and thus the surface of the second growth layer (32) is flattened. Further, growth takes place laterally so as to fill the depressions of the surface of the first growth layer (31). Thus, dislocation extending from the first growth layer (31) bends laterally and density of dislocation propagating to the surface of the second growth layer (32) is greatly lowered.
Abstract:
A method for growing nitride III-V compound semiconductor layers, comprises the steps of: growing a first BwAlxGayInzN layer (where 0≤w≤1, 0≤x≤1, 0≤y≤1, 0≤z≤1 and w+x+y+z=1) on a substrate by first vapor deposition at a growth rate not higher than 4 mu m/h; and growing a second BwAlxGayInzN layer (where 0≤w≤1, 0≤x≤1, 0≤y≤1, 0≤z≤1 and w+x+y+z=1) on the first BwAlxGayInzN layer by second vapor deposition at a growth rate higher than 4 mu m/h and not higher than 200 mu m/h. A method for fabricating a nitride III-V compound semiconductor substrate, comprises the steps of: growing a first BwAlxGayInzN layer (where 0≤w≤1, 0≤x≤1, 0≤y≤1, 0≤z≤1 and w+x+y+z=1) on a substrate by first vapor deposition at a growth rate not higher than 4 mu m/h; growing a second BwAlxGayInzN layer (where 0≤w≤1, 0≤x≤1, 0≤y≤1, 0≤y≤1 and w+x+y+z=1) on the first BwAlxGayInzN layer by second vapor deposition at a growth rate higher than 4 mu m/h and not higher than 200 mu m/h; and removing the substrate.
Abstract:
An unevenness inspection system includes: an image pickup section configured to acquire a picked-up image of an inspection target; an image generation section configured to generate a color-unevenness inspection image and a luminance-unevenness inspection image, based on the picked-up image; a calculation section configured to use both of the color-unevenness inspection image and the luminance-unevenness inspection image to calculate an evaluation parameter; and an inspection section configured to use the calculated evaluation parameter to perform unevenness inspection. The image generation section performs image separation processing to separate a color component and a luminance component on the picked-up image, to generate a color-component image and a luminance-component image, and individually performs filter processing taking account of visual spatial frequency characteristics on the color-component image and the luminance-component image to respectively generate the color-unevenness inspection image and the luminance-unevenness inspection image, based on the filter-processed color-component image and the filter-processed luminance-component image. The calculation section calculates the evaluation parameter in consideration of unevenness visibility with respect to both of color and luminance.
Abstract:
PROBLEM TO BE SOLVED: To provide a group III-V nitride-based compound layer which has improved qualities and is obtained by a simplified manufacturing process, and to provide a substrate using the same. SOLUTION: A first growth layer 21 is grown on a base body 10 for growth in such a manner that the growth velocity in the direction perpendicular to the growth surface is higher than 10 μm/h. A second growth layer 22 is then grown in such a manner that the growth velocity in the direction perpendicular to the growth surface is not higher than 10 μm/h. Although the surface of the first growth layer 21 is coarse, the recesses in the surface of the first growth layer 21 are buried and the surface of the second growth layer 22 is flattened by growing the second growth layer 22 at a growth velocity lower than that of the first growth layer 21. Since the second growth layer 22 grows in a lateral direction so as to bury each recess in the surface of the first growth layer 21, each dislocation D taken over from the first growth layer 21 is bent in a lateral direction at a projected part of the surface, and the density of dislocations D propagated to the surface of the second growth layer 22 is largely reduced and becomes 10 6 pieces/cm 2 order. COPYRIGHT: (C)2008,JPO&INPIT
Abstract:
PROBLEM TO BE SOLVED: To cool light emitting diodes without taking in dust or the like, and to reduce differences in a temperature distribution. SOLUTION: In this backlight device in which a plurality of light sources 21 are disposed to illuminate a transmission type display panel from its back side, a cooling part 30 in which a passage 31 for cooling water to circulate is provided just under the light sources 21. COPYRIGHT: (C)2007,JPO&INPIT
Abstract:
PROBLEM TO BE SOLVED: To realize a back light system of a thin type for surface emitting of white light without luminance unevenness while using inexpensive light emitting diodes as light sources. SOLUTION: The back light system 140 is realized by providing the back light system with the optical filter 10 which is composed of dielectric multilayered films alternately laminated with a plurality of low-refractive index layers, and high-refractive index layers having the refractive index higher than that of the low-refractive index layers and has the transmittance according to incident angles respectively with the incident red light of the prescribed wavelength band, the green light of the prescribed wavelength band and the blue light of the prescribed wavelength band. COPYRIGHT: (C)2006,JPO&NCIPI
Abstract:
PROBLEM TO BE SOLVED: To provide a method for growing a nitride based III-V compound semiconductor layer which can produce a nitride based III-V compound semiconductor substrate having good crystallinity and no surface roughness nor crack with high productivity. SOLUTION: A thin GaN layer 2 is grown rate of 4 μm/h or less on a c-face sapphire substrate 1 by MOCVD or MBE, and then a sufficiently thick GaN layer 3 is grown on the GaN layer 2 at a rate higher than 4 μm/h but not higher than 200 μm/h by hydride VPE. Subsequently, the c-face sapphire substrate 1 is removed by etching or lapping to obtain a GaN substrate comprising the GaN layers 2, 3. Finally, the surface of the GaN layer 2 or 3 being used as a growth surface is etched or polished to bring about a high quality surface state.