# US 12,763,550 B2 · Multiphase growth sequence for forming a vertical cavity surface emitting laser > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,763,550 B2 - Document ID: US12763550B2 - Status: Granted - Kind: B2 - Application number: 17/364,443 - Filed: 2021-06-30 - Published: 2022-06-30 - Granted: 2026-10-13 - Earliest claimed: 2020-12-31 - Assignees: Lumentum Operations LLC - Applicants: Lumentum Operations LLC - Inventors: Guowei Zhao; Jun Yang; Ajit Vijay Barve; Matthew Glenn Peters - Web page: https://patentgrep.com/patent/US12763550B2 ## CPC - H01S 5/18311: {using selective oxidation} - H01S 5/18358: {containing spacer layers to adjust the phase of the light wave in the cavity} - H01S 5/3095: {Tunnel junction} - H01S 5/3412: {quantum box or quantum dash} - H01S 5/34306: {emitting light at a wavelength longer than 1000nm, e.g. InP based 1300 and 1500nm lasers} - H01S 2304/02: MBE - H01S 2304/04: MOCVD or MOVPE - H01S: DEVICES USING THE PROCESS OF LIGHT AMPLIFICATION BY STIMULATED EMISSION OF RADIATION [LASER] TO AMPLIFY OR GENERATE LIGHT; DEVICES USING STIMULATED EMISSION OF ELECTROMAGNETIC RADIATION IN WAVE RANGES OTHER THAN OPTICAL ## Abstract A method of forming a vertical cavity surface emitting laser (VCSEL) device using a multiphase growth sequence includes forming a first mirror over a substrate; forming an active region (e.g., a dilute nitride active region) over the first mirror; forming an oxidation aperture (OA) layer over the active region; forming a spacer on a surface of the OA layer; and forming a second mirror over the spacer. The active region is formed using a molecular beam epitaxy (MBE) process during an MBE phase of the multiphase growth sequence and the second mirror is formed using a metal-organic chemical vapor deposition (MOCVD) process during an MOCVD phase of the multiphase growth sequence. ## Claims ### Claim 1 A method of forming a vertical cavity surface emitting laser (VCSEL) device using a multiphase growth sequence, comprising: forming a first mirror over a substrate using a first metal-organic chemical vapor deposition (MOCVD) process during a first MOCVD phase of the multiphase growth sequence; forming an active region over the first mirror using a molecular beam epitaxy (MBE) process during an MBE phase of the multiphase growth sequence; forming an oxidation aperture (OA) layer over the active region; forming, during the MBE phase, a first portion of a spacer on a surface of the OA layer, wherein the spacer comprises gallium arsenide (GaAs); forming an interim cap over the spacer, wherein the interim cap comprises at least one of indium arsenide (InAs) or arsenic (As); causing the interim cap and at least a portion of the first portion of the spacer to be removed, such that, after removal, a top surface of the first portion of the spacer coincides with a local minimum of a standing wave of an optical field of the VCSEL device; forming a second portion of the spacer on the first portion of the spacer using a second MOCVD process during a second MOCVD phase of the multiphase growth sequence and after removal of the interim cap; forming a tunnel junction over the second portion of the spacer using the second MOCVD process; and forming a second mirror over the tunnel junction using the second MOCVD process. ### Claim 2 (depends on 1) The method of claim 1, wherein the VCSEL device is configured to emit an output beam, wherein the output beam is associated with a wavelength range of 1200-1600 nanometers. ### Claim 3 (depends on 1) The method of claim 1, wherein: the substrate comprises GaAs; the active region comprises at least one of a dilute nitride quantum well or an indium gallium arsenide (InGaAs) or InAs quantum dot layer; the spacer comprises a p-doped GaAs layer; the first mirror and the second mirror each comprise a set of alternating GaAs layers and aluminum gallium arsenide (AlGaAs) layers; and the interim cap comprises As. ### Claim 4 (depends on 1) The method of claim 1, wherein: the first mirror is an n-doped distributed Bragg reflector (DBR); and the second mirror is a p-doped DBR. ### Claim 5 (depends on 1) The method of claim 1, wherein: the first mirror is an n-doped distributed Bragg reflector (DBR); and the second mirror is an n-doped DBR. ### Claim 6 (depends on 1) The method of claim 1, wherein the second mirror is formed on a surface of the tunnel junction. ### Claim 7 (depends on 1) The method of claim 1, wherein at least one of the first mirror or the OA layer is formed using the MBE process during the MBE phase. ### Claim 8 (depends on 1) The method of claim 1, wherein the OA layer and the interim cap are formed using the MBE process during the MBE phase, and wherein causing the interim cap to be removed further comprises: causing the interim cap to be removed before the second mirror is formed using the MOCVD process during the second MOCVD phase. ### Claim 9 (depends on 1) The method of claim 1, wherein the first mirror is formed using an additional MOCVD process during an additional MOCVD phase, and the method further comprises: forming an additional spacer on the first mirror using the additional MOCVD process during the additional MOCVD phase. ### Claim 10 (depends on 9) The method of claim 9, further comprising: forming another interim cap over the additional spacer using the additional MOCVD process during the additional MOCVD phase, and wherein causing the interim cap to be removed further comprises: causing the other interim cap to be removed before the active region is formed using the MBE process during the MBE phase. ### Claim 11 (depends on 1) The method of claim 1, wherein the spacer has a particular optical thickness that causes the regrowth interface to coincide with the local minimum. ### Claim 12 A method of forming a vertical cavity surface emitting laser (VCSEL) device using a multiphase growth sequence, comprising: forming a first mirror over a substrate using a first metal-organic chemical vapor deposition (MOCVD) process during a first MOCVD phase of the multiphase growth sequence; forming, during the first MOCVD phase, a first portion of a first spacer on a surface of the first mirror, wherein the first spacer comprises gallium arsenide (GaAs); forming an interim cap over the first spacer, wherein the interim cap comprises at least one of indium arsenide (InAs) or arsenic (As); causing the interim cap and at least a portion of the first portion of the first spacer to be removed, such that, after removal, a top surface of the first portion of the first spacer coincides with a local minimum of a standing wave of an optical field of the VCSEL device; forming a second portion of the first spacer on the first portion of the first spacer using a molecular beam epitaxy (MBE) process during an MBE phase of the multiphase growth sequence and after removal of the interim cap; forming an active region over the first spacer using the MBE process during the MBE phase; forming an oxidation aperture (OA) layer over the active region; forming a second spacer on a surface of the OA layer; and forming a second mirror over the second spacer using a second MOCVD process during a second MOCVD phase of the multiphase growth sequence. ### Claim 13 (depends on 12) The method of claim 12, wherein the interim cap is formed using the first MOCVD process during the first MOCVD phase, and wherein causing the interim cap to be removed further comprises: causing the interim cap to be removed during a transition period between the first MOCVD phase and the MBE phase. ### Claim 14 (depends on 13) The method of claim 13, wherein: the substrate comprises GaAs; the active region comprises at least one of a dilute nitride quantum well or an indium gallium arsenide (InGaAs) or InAs quantum dot layer; the first spacer comprises at least one of an undoped GaAs layer or an n-doped GaAs layer; the second spacer comprises a p-doped GaAs layer; the first mirror and the second mirror each comprise a set of alternating GaAs layers and aluminum gallium arsenide (AlGaAs) layers; and the interim cap comprises As. ### Claim 15 (depends on 12) The method of claim 12, further comprising: cleaning a surface of the first spacer during a transition period between the first MOCVD phase and the MBE phase. ### Claim 16 (depends on 12) The method of claim 12, further comprising: forming a tunnel junction on a surface of the second spacer using the second MOCVD process during the second MOCVD phase, wherein the second mirror is formed on a surface of the tunnel junction. ### Claim 17 A method of forming a vertical cavity surface emitting laser (VCSEL) device using a multiphase growth sequence, comprising: forming a first mirror over a substrate; forming an active region over the first mirror using a molecular beam epitaxy (MBE) process during an MBE phase of the multiphase growth sequence; forming, during the MBE phase, an oxidation aperture (OA) layer over the active region; forming, during the MBE phase, a first portion of a spacer on a surface of the OA layer, wherein the spacer comprises gallium arsenide (GaAs); forming an interim cap over the spacer, wherein the interim cap comprises at least one of indium arsenide (InAs) or arsenic (As); causing the interim cap and at least a portion of the first portion of the spacer to be removed, such that, after removal, a top surface of the first portion of the spacer coincides with a local minimum of a standing wave of an optical field of the VCSEL device; forming a second portion of the spacer on the first portion of the spacer using a metal-organic chemical vapor deposition (MOCVD) process during an MOCVD phase of the multiphase growth sequence and after removal of the interim cap; forming, during the MOCVD phase, a second mirror over the spacer; and forming, during the MOCVD phase, a cap layer over the second mirror. ### Claim 18 (depends on 17) The method of claim 17, wherein the interim cap is formed using the MBE process during the MBE phase, and wherein causing the interim cap to be removed further comprises: causing the interim cap to be removed by an evaporation process during a transition period between the MBE phase and the MOCVD phase. ### Claim 19 (depends on 18) The method of claim 18, wherein: the substrate comprises GaAs; the active region comprises at least one of a dilute nitride quantum well or an indium gallium arsenide (InGaAs) or InAs quantum dot layer; the spacer comprises a p-doped GaAs layer; the first mirror and the second mirror each comprise a set of alternating GaAs layers and aluminum gallium arsenide (AlGaAs) layers; and the interim cap comprises As. ### Claim 20 (depends on 17) The method of claim 17, further comprising: forming a tunnel junction on a surface of the spacer using the MOCVD process during the MOCVD phase, wherein the second mirror is formed on a surface of the tunnel junction.