Light emitting devices with improved light extraction efficiency

A light emitting device having a stack of layers including semiconductor layers comprising an active region, said device comprising:

• a transparent optical element bonded to a surface of the stack by a bonding layer, wherein the bonding layer is selected from the group consisting of metal oxide, tungsten oxide, titanium oxide, nickel oxide, zirconium oxide, indium tin oxide, and chromium oxide.

A light emitting device having a stack of layers including semiconductor layers comprising an active region, said device comprising:

• a transparent optical element bonded to a surface of the stack by a bonding layer, wherein the bonding layer includes luminescent material,
• wherein a smallest ratio of a length of a base of said optical element to a length of said surface is greater than one.