US 12,237,450 B2
Metallic structure for optical semiconductor device, method for producing the same, and optical semiconductor device using the same
Yasuo Kato, Anan (JP); and Kazuya Matsuda, Anan (JP)
Assigned to NICHIA CORPORATION, Anan (JP)
Filed by NICHIA CORPORATION, Anan (JP)
Filed on Sep. 17, 2021, as Appl. No. 17/478,376.
Application 17/478,376 is a division of application No. 16/584,038, filed on Sep. 26, 2019, granted, now 11,152,547.
Claims priority of application No. 2018-182721 (JP), filed on Sep. 27, 2018.
Prior Publication US 2022/0005986 A1, Jan. 6, 2022
Int. Cl. H01L 33/62 (2010.01); H01L 23/495 (2006.01); H01L 33/56 (2010.01)
CPC H01L 33/56 (2013.01) [H01L 23/49582 (2013.01); H01L 33/62 (2013.01)] 7 Claims
OG exemplary drawing
 
1. A method for producing a metallic structure for an optical semiconductor device, which comprises forming metallic layers on a conductive base body in the following order of steps:
forming a nickel or nickel alloy plated layer on the conductive base body,
optionally forming a rhodium, palladium, rhodium alloy, or palladium alloy plated layer on the nickel or nickel alloy plated layer,
forming a gold or gold alloy plated layer on the nickel or nickel alloy plated layer or optionally on the rhodium, palladium, rhodium alloy, or palladium alloy plated layer if it is present, and
forming an indium or indium alloy plated layer on the gold or gold alloy plated layer,
wherein the indium or indium alloy plated layer has a thickness in a range of 0.002 μm or more and 0.3 μm or less,
wherein the metallic structure has a chromaticity represented by the b* value in the L*a*b* color system in a range of 21 or more and 40 or less, and
wherein the metallic structure has a reflectance in a range of 30% or more and 49% or less with respect to light having a light emission peak wavelength at 450 nm.