1. A semiconductor device comprising:
a semiconductor thin-film piece,
a substrate; and
a bonding layer provided on a surface of the substrate, said bonding layer having a surface which is wider than the semiconductor thin-film piece, and to which the semiconductor thin-film is bonded, wherein
said surface of said bonding layer is substantially flat; and
said surface of said bonding layer is higher than any other part of the substrate.
2. The semiconductor device according to claim 1, wherein the semiconductor thin-film piece has a light-emitting semiconductor element, the substrate comprises a Si substrate, and includes a chip area in which a drive circuit for driving said light-emitting element is formed, wherein said semiconductor thin-film piece is bonded in the chip area.
3. The semiconductor device according to claim 1, wherein said bonding layer is a metal layer.
4. The semiconductor device according to claim 1, wherein said bonding layer is an insulating layer.
5. The semiconductor device according to claim 1, wherein said bonding layer is a semiconductor layer.
6. The semiconductor device according to claim 1, wherein said bonding layer is a laminate of a metal layer and an insulation film layer.
7. The semiconductor device according to claim 6, wherein said bonding layer comprises an interconnection layer.
8. The semiconductor device according to claim 6, wherein said bonding layer has an uppermost layer which is metal.
9. An LED print head comprising a semiconductor device according to claim 1.
10. An image-forming apparatus comprising an LED print head according to claim 9, and a photosensitive drum disposed facing said LED print head.
11. The semiconductor device according to claim 1, wherein said semiconductor thin-film piece layer comprises a compound semiconductor epitaxial layer or inorganic semiconductor layer.
12. The semiconductor device according to claim 11, wherein said compound semiconductor epitaxial layer is formed of GaAsP, InP, AlGaInP, InGaAsP, GaN, InGaN, or AlGaN.
13. The semiconductor device according to claim 11, wherein said inorganic semiconductor layer is formed of monocrystalline silicon layer or polycrystalline silicon layer.
14. The semiconductor device according to claim 1, wherein said substrate is formed of silicon, glass, ceramic, metal, plastic or quartz.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A process for preparing phosphor particles of a doped host oxide which comprises:
preparing an aqueous solution of salts of the host ion and of the dopant ion which is thorium, titanium, silicon, bismuth, copper, silver, tungsten or chromium and a water soluble compound, which decomposes under the reaction conditions to convert said salts into hydroxycarbonate,
heating the solution so as to cause said compound to decompose,
recovering the resulting precipitate and
calcining it at a temperature of at least 500 C., with the proviso that the oxide is not a ternary oxide when the dopant is titanium or chromium.
2. A process for preparing phosphor particles of the formula (Zr1Zs2)zOy:RE where Z1 and Z2 are two different elements of the host oxide and rs1, 2ya.z where a is the overall valence of Zr1Zs2 and RE represents a dopant ion of a rare earth, manganese, bismuth, copper or chromium which comprises:
preparing an aqueous solution of salts of the host ion and of the dopant ion and a water soluble compound which decomposes under the reaction conditions to convert said salts into hydroxycarbonate,
heating the solution so as to cause said compound to decompose;
recovering the resulting precipitate and
calcining it at a temperature of at least 500 C.
3. A process for preparing phosphor particles of the formula ZzOy:RE where RE is a rare earth, manganese, bismuth, copper or chromium and Z is tin, indium, niobium, molybdenum, tantalum, tungsten or zinc which comprises
preparing an aqueous solution of salts of the host ion and of the dopant ion and a water soluble compound which decomposes under the reaction conditions to convert said salts into hydroxycarbonate,
heating the solution so as to cause said compound to decompose;
recovering the resulting precipitate and
calcining it at a temperature of at least 500 C.
4. A process for preparing phosphor particles of the formula:
ZpXq oxide:RE where RE is a dopant ion of a rare earth, manganese, thorium, titanium, silicon, bismuth, copper, silver, tungsten or chromium, X is a metal or metalloid, Z is zinc, barium, calcium, cadmium, magnesium, strontium, zirconium, scandium, lanthanum, hafnium, titanium, vanadium, niobium, chromium, molybdenum, tungsten, beryllium, bismuth, indium, lutetium, lithium or lead and p and q denote the atomic proportion of Z and X respectively, which comprises:
preparing an aqueous solution of salts of the host ion and of the dopant ion and a water soluble compound which decomposes under the reaction conditions to convert said salts into hydroxycarbonate,
heating the solution so as to cause said compound to decompose;
recovering the resulting precipitate and calcining it at a temperature of at least 500 C.
5. A process for preparing phosphor particles of the formula:
ZpXq oxide:RE where RE is a dopant ion of a rare earth, manganese, thorium, titanium, silicon, bismuth, copper, silver, tungsten or chromium, Z is a metal or metalloid, X is gallium, tungsten, germanium, boron, vanadium, titanium, niobium, tantalum, molybdenum, chromium, zirconium, hafnium, manganese, phosphorus, copper, tin, lead or cerium and p and q denote the atomic proportion of Z and X respectively,- which comprises:
preparing an aqueous solution of salts of the host ion and of the dopant ion and a water soluble compound which decomposes under the reaction conditions to convert said salts into hydroxycarbonate,
heating the solution so as to cause said compound to decompose;
recovering the resulting precipitate and
calcining it at a temperature of at least 500 C.
6. A process for preparing phosphor particles of the formula: ZpXq oxide: RE where RE is a dopant ion of a rare earth which is not terbium, europium, cerium, thulium, samarium, holmium, erbium, dysprosium or praseodymium, X is a metal, metalloid or non-metal, Z is a metal or metalloid and p and q denote the atomic proportion of Z and X respectively, which comprises:
preparing an aqueous solution of salts of the host ion and of the dopant ion and a water soluble compound which decomposes under the reaction conditions to convert said salts into hydroxycarbonate,
heating the solution so as to cause said compound to decompose;
recovering the resulting precipitate and
calcining it at a temperature of at least 500 C.
7. A process according to any one of the preceding claims in which at least one of the salts is a chloride.
8. A process according to any one of the preceding claims in which the salts are formed in situ from the corresponding oxides and the corresponding acid.
9. A process according to any one of the preceding claims in which the said water soluble compound is urea or oxalic acid.
10. A process according to claim 9 in which the solution is heated to a temperature of 70 to 100 C.
11. A process according to any one of the preceding claims in which the dopant is added in an amount to provide a concentration of 1 to 10% in the particles.
12. A process according to any one of the preceding claims in which the heating step is carried out in a sealed vessel.
13. A process according to any one of the preceding claims in which the calcination takes place in air or a reducing atmosphere.
14. A process according to claim 13 in which the calcination takes place at a temperature of at least the Tamman temperature of the host oxide.
15. A process according to claim 14 in which the calcination takes place at a temperature of at least 1050 C. for 1 to 5 hours.
16. A process according to any one of the preceding claims in which the particles are substantially monocrystalline.
17. A process according to any one of the preceding claims in which the particles have a size from 50 to 150 nm.
18. A process according to claim 1 substantially as hereinbefore described.
19. Phosphor particles whenever prepared by a process as claimed in any one of the preceding claims.
20. Substantially monocrystalline particles, and particles in the form of composites of such crystals, having the formula:
Z=hd zOy:RE
as defined in claim 3 or 4.
21. Particles of the formula: (Zr1Zs2)zOy:RE as defined in claim 2.
22. Particles of the formula: ZpXq oxide:RE as defined in claim 5 or 6.
23. Particles according to any one of claims 20 to 22 having one or more of the features of claims 11 and 17.
24. A plastics material which comprises particles as claimed in any one of claims 19 to 23.
25. A material according to claim 24 which is 0.5 to 15 microns thick.
26. A material according to claim 24 or 25 which contains 2 to 35% by weight of the particles based on the weight of the material.
27. A material according to any one of claims 24 to 26 which is made of an electrically conducting polymer.
28. A material according to any one of claims 24 to 27 which is made of polyacrylic acid, polymethylmethacrylate or polystyrene.