| 摘要 |
PROBLEM TO BE SOLVED: To obtain a light-emitting element having excellent durability, by thermally processing and polycrystallizing a porous Si substrate with Er electrodeposited to pores. SOLUTION: After forming many pores on the surface of a P-type Si substrate 1 by electrochemical etching or the like, an electrolysis is performed in an electrolyte containing Er ion with Si substrate as a negative pole (methanol solution with ErCl3 5 to 50 wt.%). Er stuck to the surface of pores is oxidized and converted to an illuminant Er2 O3 and heat-treated, and the porous structure is changed to polycrystalline structure. The substrate may be either single crystal or polycrystalline or amorphous Si, and conditions at a high temperature for a short time is desired for oxidation treatment. At the rear side of Si substrate, B is ion implanted and P<+> layer is formed and Al electrode 2 is vapor deposited. On the surface side of the substrate, a light- emitting layer 3 containing a high concentration of Er is formed by the method stated above, on which an n<+> Si epitaxial growth film 4 heavily doped with P on the layer 3. V-groove is formed by mesa etching on this multilayered film, an oxidized film 5 formed on that surface is removed by etching, Al electrode 6 is vapor deposited on the growth film, and a p-n junction type light-emitting element can be obtained. |
