Abstract: A semiconductor radiation detector 10 comprises a Si substrate 11 of an N-ype of low resistance, an arsenic coating layer 12 formed on the Si substrate, and a CdTe growth layer 13 of a P-type of high resistance laminated and formed thereon by the MOVPE method, which is divided into multiple plane elements of a hetero junction structure by means of division grooves 15 extending from the CdTe growth layer surface to the Si substrate. The Si substrate is heated in a hydrogen reducing atmosphere of a high temperature, and its surface is cleaned. On this Si substrate, GaAs powder or GaAs crystals are thermally decomposed, and coated by arsenic molecule to an extent at about one molecular layer, and an arsenic coating layer is thereby formed. On the Si substrate forming the arsenic coating layer, a CdTe growth layer is formed by the MOVPE method to a film thickness of about 0.2 to 0.5 mm in an atmosphere of about 450 to 500 deg. C.

Abstract: The present invention provides surface coated phosphors useful in field emission displays and vacuum fluorescent displays. The surface coated phosphor comprises a thin coating of rare earth oxide, e.g., yttrium oxide, disposed on an uncoated phosphor such as a sulfide phosphor. The present invention further provides a process for preparing a surface coated phosphor comprising contacting the uncoated phosphor with a rare earth hydroxide gel solution to obtain a rare earth hydroxide gel coated phosphor, drying the gel coated phosphor to remove solvent residues, and heat treating the dried rare earth hydroxide gel coated phosphor. The surface coated phosphors of the present invention have improved cathodoluminescence efficiency, coulombic aging resistance, chemical, and/or oxidative stability.

Abstract: A semiconductor radiation detector 10 comprises a Si substrate 11 of an N-ype of low resistance, an arsenic coating layer 12 formed on the Si substrate, and a CdTe growth layer 13 of a P-type of high resistance laminated and formed thereon by the MOVPE method, which is divided into multiple plane elements of a hetero junction structure by means of division grooves 15 extending from the CdTe growth layer surface to the Si substrate. The Si substrate is heated in a hydrogen reducing atmosphere of a high temperature, and its surface is cleaned. On this Si substrate, GaAs powder or GaAs crystals are thermally decomposed, and coated by arsenic molecule to an extent at about one molecular layer, and an arsenic coating layer is thereby formed. On the Si substrate forming the arsenic coating layer, a CdTe growth layer is formed by the MOVPE method to a film thickness of about 0.2 to 0.5 mm in an atmosphere of about 450 to 500 deg. C.

Abstract: The present invention provides surface coated phosphors useful in field emission displays and vacuum fluorescent displays. The surface coated phosphor comprises a thin coating of rare earth oxide, e.g., yttrium oxide, disposed on an uncoated phosphor such as a sulfide phosphor. The present invention further provides a process for preparing a surface coated phosphor comprising contacting the uncoated phosphor with a rare earth hydroxide gel solution to obtain a rare earth hydroxide gel coated phosphor, drying the gel coated phosphor to remove solvent residues, and heat treating the dried rare earth hydroxide gel coated phosphor. The surface coated phosphors of the present invention have improved cathodoluminescence efficiency, coulombic aging resistance, chemical, and/or oxidative stability.

Abstract: The present invention provides surface coated phosphors useful in field emission displays and vacuum fluorescent displays. The surface coated phosphor comprises a thin coating of rare earth oxide, e.g., yttrium oxide, disposed on an uncoated phosphor such as a sulfide phosphor. The present invention further provides a process for preparing a surface coated phosphor comprising contacting the uncoated phosphor with a rare earth hydroxide gel solution to obtain a rare earth hydroxide gel coated phosphor, drying the gel coated phosphor to remove solvent residues, and heat treating the dried rare earth hydroxide gel coated phosphor. The surface coated phosphors of the present invention have improved cathodoluminescence efficiency, coulombic aging resistance, chemical, and/or oxidative stability.

Abstract: The present invention provides surface coated phosphors useful in field emission displays and vacuum fluorescent displays. The surface coated phosphor comprises a thin coating of rare earth oxide, e.g., yttrium oxide, disposed on an uncoated phosphor such as a sulfide phosphor. The present invention further provides a process for preparing a surface coated phosphor comprising contacting the uncoated phosphor with a rare earth hydroxide gel solution to obtain a rare earth hydroxide gel coated phosphor, drying the gel coated phosphor to remove solvent residues, and heat treating the dried rare earth hydroxide gel coated phosphor. The surface coated phosphors of the present invention have improved cathodoluminescence efficiency, coulombic aging resistance, chemical, and/or oxidative stability.

Abstract: The present invention provides surface coated phosphors useful in field emission displays and vacuum fluorescent displays. The surface coated phosphor comprises a thin coating of rare earth oxide, e.g., yttrium oxide, disposed on an uncoated phosphor such as a sulfide phosphor. The present invention further provides a process for preparing a surface coated phosphor comprising contacting the uncoated phosphor with a rare earth hydroxide gel solution to obtain a rare earth hydroxide gel coated phosphor, drying the gel coated phosphor to remove solvent residues, and heat treating the dried rare earth hydroxide gel coated phosphor. The surface coated phosphors of the present invention have improved cathodoluminescence efficiency, coulombic aging resistance, chemical, and/or oxidative stability.

Abstract: Disclosed is an avalanche photodiode wherein a light absorption layer and a multiplication layer are first grown on substrate. The multiplication layer is then mesa-etched and another semiconductor layer is second grown on the mesa-etched multiplication layer. A dopant having a conductivity opposite to that of the above layers is introduced from the top of the another semiconductor layer to form a doped region extending inside the mesa portion and p-n junction is therefore formed inside the mesa-etched portion. This causes the distribution of multiplication in the active area to become uniform, since the rough surface of the top of the mesa-etched portion exists outside the multiplication region.