Patent ID: 7495322

Claim:
A light-emitting device, comprising: a submount comprising a mount base made of an electrically insulating material, at least one light-emitting diode chip mounted thereon and electrically conducting lines formed on the mount base to be connected electrically to the light-emitting diode chip; and a first plate for heat transfer comprising a metallic plate, wherein a first plane of the mount base opposed to the metallic plate of the first plate is bonded thermally to said first plate, wherein the mount base comprises a recess, and the at least one light-emitting diode chip is mounted on a bottom of the recess, wherein at least one groove is provided on the first plane of the mount base, and wherein a number of said at least one groove is equal to or larger than two, the grooves have different depths, and depth of the grooves increases toward a region just below the light-emitting diode chip.