VCSEL array with different emitter structures
A VCSEL array includes VCSEL structures on a substrate. Each VCSEL structure includes a first reflector region over the substrate, an active region over the first reflector region, a second reflector region over the active region, and an oxide aperture proximate to the active region. An oxide aperture of a VCSEL structure that is in a central region of the VCSEL array is larger than an oxide aperture of a VCSEL structure that is in an edge region of the VCSEL array.
1 . A Vertical Cavity Surface Emitting Laser (VCSEL) array, comprising:
a substrate; and
a plurality of VCSEL structures over the substrate, each VCSEL structure comprising:
a first reflector region formed over the substrate;
an active region formed over the first reflector region;
a second reflector region formed over the active region; and
an oxide aperture formed proximate to the active region,
wherein the plurality of VCSEL structures include a first VCSEL structure that is in a central region of the VCSEL array and a second VCSEL structure that is in an edge region of the VCSEL array, a radial dimension of an oxide aperture of the first VCSEL structure approximately equals a radial dimension of an oxide aperture of the second VCSEL structure, and a second reflector region of the first VCSEL structure is larger than a second reflector region of the second VCSEL structure.
2 . The VCSEL array of claim 1 , wherein the first second reflector region of the first VCSEL structure comprises a Distributed Bragg Reflector (DBR) structure.
3 . The VCSEL array of claim 1 , wherein the second reflector region of the first VCSEL structure has a gear shape.
4 . The VCSEL array of claim 3 , wherein a gear tooth of the second reflector region of the first VCSEL structure is larger than a gear tooth of the second reflector region of the second VCSEL structure.
5 . The VCSEL array of claim 1 , wherein the plurality of VCSEL structures are isolated by isolation trenches or ion implantation regions.
6 . The VCSEL array of claim 1 further comprises a plurality of metal layers formed over each second reflector region.
7 . The VCSEL array of claim 6 , wherein the plurality of metal layers have a same shape with a same dimension or similar dimensions.
8 . The VCSEL array of claim 1 , wherein the plurality of VCSEL structures are divided into a plurality of groups, and dimensions of oxide apertures of one of the plurality of groups have a same value or similar values.
9 . A method for fabricating a Vertical Cavity Surface Emitting Laser (VCSEL) array, comprising:
fabricating a plurality of VCSEL structures over a substrate,
wherein fabricating each VCSEL structure comprises:
forming a first reflector region over the substrate;
forming an active region over the first reflector region;
forming a second reflector region over the active region; and
forming an oxide aperture proximate to the active region,
wherein the plurality of VCSEL structures include a first VCSEL structure that is in a central region of the VCSEL array and a second VCSEL structure that is in an edge region of the VCSEL array, a radial dimension of an oxide aperture of the first VCSEL structure approximately equals a radial dimension of an oxide aperture of the second VCSEL structure, and a second reflector region of the first VCSEL structure is larger than a second reflector region of the second VCSEL structure.
10 . The method of claim 9 , wherein forming the second reflector region of the first VCSEL structure comprises forming a Distributed Bragg Reflector (DBR) structure.
11 . The method of claim 9 , wherein the second reflector region of the first VCSEL structure has a gear shape.
12 . The method of claim 11 , wherein a gear tooth of the second reflector region of the first VCSEL structure is larger than a gear tooth of the second reflector region of the second VCSEL structure.
13 . The method of claim 9 further comprises isolating the plurality of VCSEL structures by isolation trenches or ion implantation regions.
14 . The method of claim 9 further comprises forming a plurality of metal layers over each second reflector region.
15 . The method of claim 14 , wherein the plurality of metal layers have a same shape with a same dimension or similar dimensions.
16 . The method of claim 9 further comprises dividing the plurality of VCSEL structures into a plurality of groups, wherein dimensions of oxide apertures of one of the plurality of groups have a same value or similar values.
17 . A Vertical Cavity Surface Emitting Laser (VCSEL) array, comprising:
a substrate;
a plurality of first VCSEL structures over the substrate; and
a plurality of second VCSEL structures over the substrate,
wherein the plurality of first VCSEL structures each are closer to a central region of the VCSEL array than the plurality of second VCSEL structures, a radial dimension of oxide apertures of the plurality of first VCSEL structures approximately equals a radial dimension of oxide apertures of the plurality of second VCSEL structures, and a reflector region over an active region of the plurality of first VCSEL structures is larger than a reflector region over an active region of the plurality of second VCSEL structures.
18 . The VCSEL array of claim 17 , wherein the reflector region of the plurality of first VCSEL structures has a gear shape.
19 . The VCSEL array of claim 18 , wherein a gear tooth of the reflector region of the plurality of first VCSEL structures is larger than a gear tooth of the reflector region of the plurality of second VCSEL structures.
20 . The VCSEL array of claim 17 , wherein a metal layer over the reflector region of the plurality of first VCSEL structures and a metal layer over the reflector region of the plurality of second VCSEL structures have a same shape with a same dimension or similar dimensions.