Encapsulated laser diode for heat-assisted magnetic recording
A magnetic write head is disclosed that includes a slider that includes a laser diode having a light-emitting edge or surface of a laser diode and an optical waveguide. The disclosed magnetic write head also includes a dielectric layer disposed in a gap between the laser diode and an input to the optical waveguide. The dielectric layer fills the gap completely and provides a low-loss optical pathway for the laser diode to the input of the optical waveguide. Also disclosed is a method that includes spinning on a dielectric in a gap between the light-emitting surface and the optical waveguide coupler, wherein after the spinning on, the laser diode is optically coupled to the optical waveguide coupler through the dielectric.
1. A magnetic write head, comprising:
a slider that includes a laser diode having a light-emitting edge or surface;
an optical waveguide; and
a spin-on-dielectric disposed in a gap between the optical waveguide and the light-emitting edge or surface, the dielectric configured to optically couple the laser diode to the optical waveguide,
wherein the dielectric has a refractive index greater than about 1.6.
2. A magnetic write head according to claim 1 , wherein the slider has a laser-in-slider configuration.
3. A magnetic write head according to claim 1 , wherein the dielectric comprises a metal oxide.
4. A magnetic write head according to claim 3 , wherein the metal oxide comprises, aluminum, yttrium, hafnium, magnesium, or silicon.
5. A magnetic write head according to claim 1 , wherein the spin-on-dielectric comprises an organic polymer.
6. A magnetic write head according to claim 5 , wherein the organic polymer is curable by exposure to actinic radiation.
7. A magnetic write head according to claim 5 , wherein the organic polymer comprises a fluorene moiety.
8. A magnetic write head according to claim 1 , wherein the gap ranges from between about 0.5 μm and about 2.5 μm.
9. A magnetic write head according to claim 1 , wherein the gap has a ratio of 5-6 between a longest dimension of the gap and a shortest dimension of the gap.
10. A magnetic write head according to claim 1 , wherein the dielectric has an average transmission of about 90% or greater at wavelengths emitted by the laser diode.
11. A method, comprising:
attaching a slider comprising a laser diode to a magnetic write head, the laser oriented so that a light-emitting edge or surface of the laser diode faces an optical waveguide coupler; and
spinning on a dielectric in a gap between the light-emitting surface and the optical waveguide coupler, wherein after the spinning on, the laser diode is optically coupled to the optical waveguide coupler through the dielectric.
12. A method according to claim 11 , wherein the gap ranges from between about 0.5 μm and about 2.5 μm.
13. A method according to claim 11 , wherein the gap has a ratio of 5-6 between a longest dimension of the gap and a shortest dimension of the gap.
14. A method according to claim 11 , wherein the dielectric has a refractive index greater than about 1.6.
15. A method according to claim 11 , wherein the dielectric comprises a spin-on dielectric.
16. A method according to claim 15 , wherein the dielectric comprises an organic polymer.
17. A method according to claim 16 , wherein the organic polymer is curable by exposure to actinic radiation.
18. A method according to claim 16 , wherein the organic polymer comprises a fluorene moiety.
19. A method according to claim 11 , wherein the dielectric has an average transmission of about 90% or greater at wavelengths emitted by the laser diode.
20. A method according to claim 10 , wherein spinning on the dielectric comprises spinning on the dielectric at a variable speed between about 1000 and 3000 rpm for 10 minutes.
21. A method according to claim 10 , further comprising pre-baking the magnetic write head at a temperature of about 60° C. for 10 minutes prior to the spinning on.
22. A method according to claim 10 , further comprising curing the dielectric after the spinning on.
23. A method according to claim 21 , wherein curing the dielectric comprises exposing the dielectric to ultraviolet light with a level of power of 200-400 mW/cm 2 for a period of 1 minute.