摘要:
[Object] To provide a highly reliable circuit board which can be used for a long period of time and an electronic apparatus including this circuit board and an electronic component mounted thereon. [Solution] The circuit board includes a ceramic sintered body (11) and a metal wiring layer (13) provided on at least one primary surface (11a) thereof with a glass layer (12) interposed therebetween, and when the cross section of the circuit board perpendicular to the primary surface (11a) of the ceramic sintered body (11) is viewed, the ratio of the length of an interface (15) between the glass layer (12) and the metal wiring layer (13) to a length (12a) of the glass layer (12) in a direction along the primary surface (11a) is 1.25 to 1.80. As a result, good heat dissipation characteristics can be obtained, and the metal wiring layer (13) is not likely to be peeled away from the ceramic sintered body (11) due to operation of an electronic component (21) and/or cooling/heating cycles performed by repeated on-off operations thereof, so that a highly reliable circuit board which can be used for a long period of time can be provided.
摘要:
[Problem] To provide a highly-reliable circuit board and an electronic device obtained by mounting electronic components on the circuit board, which have high bonding strength and excellent heat discharge properties, and can be used over a long period as a result of minimizing cavities in a metal wiring layer formed on a through conductor. [Solution] A circuit board (10) is provided with a through conductor (13) comprising a metal in a through hole (12) that penetrates in the thickness direction of a ceramic sintered body (11), and a metal wiring layer (14) that covers and is connected to the surface of the through conductor (13) on at least one main surface side of the ceramic sintered body (11). The through conductor (13) comprises: a first portion (13a) that is positioned on an inner wall side of the through hole (12), from one end to the other end of the through hole (12) in the thickness direction of the ceramic sintered body (11); and a second portion (13b) that adjoins the first portion (13a). The average crystal grain size in the second portion (13b) is larger than the average crystal grain size in the first portion (13a).
摘要:
There is provided a ceramics substrate for mounting a light-emitting element having high thermal conductivity which can achieve high reflectance and which can enhance heat dissipation performance to extend the lifetime of a light-emitting element. A ceramics substrate for mounting a light-emitting element includes a ceramic sintered body, the ceramic sintered body having a mounting section on which a light-emitting element is mounted, in a surface portion on a mounting section side of the ceramic sintered body, a ratio of crystal grains having a crystal grain size of 0.2 µm to 1.0 µm in equivalent circle diameter being in a range of 45% to 80%, a ratio of crystal gains having a crystal grain size of 2.0 µm to 6.0 µm in equivalent circle diameter being in a range of 5% to 15%, and a ratio of crystal grains having a crystal grain size of more than 6.0 µm in equivalent circle diameter being 2.7% or less. Therefore, the reflectance of the ceramics substrate for mounting a light-emitting element (1) can be improved, and a ceramics substrate for mounting a light-emitting element with high thermal conductivity can be produced.