| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a ceramic substrate for mounting a light-emitting element which has a high reflectance in the region from ultraviolet to infrared (350-1000 nm) of 90% or more and also has good mechanical properties. <P>SOLUTION: A ceramic substrate 1 for mounting a light-emitting element includes aluminum oxide in a content of 94 mass% or more and 97 mass% or less, silicon oxide, and at least one of calcium oxide and magnesium oxide. When pores each having an equivalent circle diameter of 0.8 μm or more are observed in a part having a surface area of 9.074×10<SP POS="POST">5</SP>μm<SP POS="POST">2</SP>in a surface 1a of the substrate 1, the ceramic substrate 1 for mounting a light-emitting element has a porosity of 2.5% or more and 4.5% or less, a number of pores of 7000 or more and 11000 or less, and a cumulative relative frequency of the equivalent circle diameter of 1.6 μm or less in the pore distribution of 70% or more. The substrate 1 has a high reflectance in the region from ultraviolet to infrared of 90% or more and also has good mechanical properties. Thus, it is suitable for a light-emitting device 21. <P>COPYRIGHT: (C)2012,JPO&INPIT |
