Sony patents laser design that blocks edge current to improve stability
Sony describes a vertical cavity surface emitting laser (VCSEL) with a specific layer structure designed to manage electrical flow. The patent details implanting ions into the outer edges of a tunnel junction layer to increase resistance there, which helps prevent current from leaking around the sides of the laser.
In the filing’s own words
A Provided is a vertical cavity surface emitting laser element that includes a first DBR, a second BR, an active layer, and a tunnel junction layer. The first DBR and the second DBR reflects light of the wavelength. The active layer is disposed between the first DBR and the second DBR. The tunnel junction layer is disposed between the first DBR and the active layer and forms a tunnel junction. Respective layers between the first DBR and the second DBR have an inner peripheral region that is on an inner peripheral side as viewed from a direction perpendicular to a layer surface, and an outer peripheral region surrounding the inner peripheral region, ions being implanted into the outer peripheral region of the tunnel junction layer, the outer peripheral region having a lower carrier concentration and a larger electric resistance than the inner peripheral region of the tunnel junction layer.
What exactly they claim (claim 1)
1. A vertical cavity surface emitting laser element, comprising: a stacked body that comprises: a first DBR (Distributed Bragg Reflector) configured to reflect light of a specific wavelength; a second DBR configured to reflect the light of the specific wavelength; an active layer between the first DBR and the second DBR; and a tunnel junction layer between the first DBR and the active layer, wherein the tunnel junction layer includes a tunnel junction, each of the active layer and the tunnel junction layer includes an inner peripheral region and an outer peripheral region, a bandgap of the outer peripheral region of the tunnel junction layer is larger than a bandgap of the inner peripheral region of the tunnel junction layer, each of the inner peripheral region and the outer peripheral region is in a direction which is perpendicular to a layer surface direction of the stacked body, the outer peripheral region surrounds the inner peripheral region, ions are implanted into the outer peripheral region of the tunnel junction layer, the outer peripheral region of the tunnel junction layer has a carrier concentration lower than a carrier concentration of the inner peripheral region of the tunnel junction layer, and the outer peripheral region of the tunnel junction layer has an electric resistance larger than an electric resistance of the inner peripheral region of the tunnel junction layer.
Facts
- Company
- Sony (SONY GROUP CORPORATION)
- Official title
- Vertical cavity surface emitting laser element and method of producing vertical cavity surface emitting laser element
- Patent number
- US12749871B2
- Application number
- 18042228
- Filed
- Aug 17, 2021
- Granted
- Sep 29, 2026
- Inventors
- 4
- Claims
- 16
Classified under
H01S 5/18327 Electricity & electronicsH01S 5/18361 Electricity & electronicsH01S 5/3095 Electricity & electronicsMore from Sony in Chips & hardware
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Summaries are simplified from the filing’s own abstract and first claim. A patent filing is not a product announcement.
Patent data and drawings: U.S. Patent and Trademark Office (USPTO). Nebula is not affiliated with or endorsed by the USPTO.