The present disclosure relates to optical systems and methods for their manufacture. An example method includes coupling a first surface of a light-emitter substrate to a reference surface of a carrier substrate. The method also includes registering a mold structure with respect to the reference surface of the carrier substrate. Furthermore, the method includes using the mold structure to form an optical material over at least a portion of the light-emitter substrate. The optical material is shaped according to a shape of the mold structure and includes at least one registration feature. The method also includes coupling an optical lens element to the optical material such that the optical lens element is registered to the at least one registration feature.

A VCSEL device includes a semiconductor substrate; a current conductive layer on the semiconductor substrate; a N-type Bragg reflector layer in contact with the current conductive layer; a P-type Bragg reflector layer above the N-type Bragg reflector layer; an active emitter layer; a current restriction layer, wherein the current restriction layer has a current restriction hole; a metal layer in contact with the semiconductor substrate, the metal layer has a through hole aligned with the current restriction hole; a P-type bonding pad in ohmic contact with the P-type Bragg reflector layer, and a portion of the P-type bonding pad is aligned with the current restriction hole and the through hole; and a N-type bonding pad in ohmic contact with the current conductive layer, and electrically separated from the P-type bonding pad. The P-type bonding pad and the N-type bonding pad are at a same side of the semiconductor substrate.

In an embodiment, a device includes: a first reflective structure including first doped layers of a semiconductive material, alternating ones of the first doped layers being doped with a p-type dopant; a second reflective structure including second doped layers of the semiconductive material, alternating ones of the second doped layers being doped with a n-type dopant; an emitting semiconductor region disposed between the first reflective structure and the second reflective structure; a contact pad on the second reflective structure, a work function of the contact pad being less than a work function of the second reflective structure; a bonding layer on the contact pad, a work function of the bonding layer being greater than the work function of the second reflective structure; and a conductive connector on the bonding layer.

A method of manufacturing a surface emitting laser includes: preparing a substrate on which a lower reflector layer, an active layer and an upper reflector layer are formed in this order from the bottom, each of the lower reflector layer and the upper reflector layer including a semiconductor multilayer film; forming an insulating film on the upper reflector layer; cleaning the substrate using isopropyl alcohol after the forming; patterning a photoresist by applying the photoresist on the insulating film and exposing the photoresist, after the cleaning; and forming a high resistance region by implanting ions into portions of the lower reflector layer, the active layer and the upper reflector layer exposed from the photoresist, after the patterning; wherein the cleaning includes cleaning the substrate with a liquid of the isopropyl alcohol and drying the substrate in a vapor of the isopropyl alcohol.

A VCSEL device includes an N-type metal substrate and laser-emitting units on the N-type metal substrate. Each laser-emitting unit includes an N-type contact layer in contact with the N-type metal substrate; an N-type Bragg reflector layer in contact with the N-type contact layer; a P-type Bragg reflector layer above the N-type Bragg reflector layer; an active emitter layer between the P-type Bragg reflector layer and the N-type Bragg reflector layer; a current restriction layer between the active emitter layer and the P-type Bragg reflector layer; a P-type contact layer in contact with the P-type Bragg reflector layer; and an insulation sidewall surrounding all edges of the N-type and P-type Bragg reflector layers, the N-type and P-type contact layers, the active emitter layer and the current restriction layer. A P-type metal substrate has through holes each aligned with a current restriction hole of a corresponding laser-emitting unit.

Disclosed herein is a laser structure comprising an active region overlying a GaAs substrate. The active region includes a dilute nitride material. The laser is configured to generate light at wavelengths greater than 1300 nm. Also disclosed herein is a photodetector comprising an absorber layer overlying a GaAs substrate. The absorber layer includes a dilute nitride material. The photodetector is configured to detect light at wavelengths greater than 1300 nm. Exemplary dilute nitride materials may include, but are not limited to, GaInNAs and GaInNAsSb. Embodiments of the disclosure may include a dilute nitride-on-GaAs laser structure and a dilute nitride-on-GaAs photodetector.

A light source comprises a GeSn active zone inserted between two contact zones. The active zone is formed directly on a silicon oxide layer by a first lateral epitaxial growth of a Ge germination layer followed by a second lateral epitaxial growth of a GeSn base layer. A cavity is formed between the contact zones by encapsulation and etching, so as to guide these lateral growths. A vertical growth of GeSn is then achieved from the base layer to form a structural layer. The active zone is formed in the stack of base and structural layers.

A vertical-cavity surface-emitting laser (VCSEL) includes a semiconductor substrate, a first reflector, a second reflector, a first electrical contact, a second electrical contact, and a through-hole via. The first reflector is disposed on a first side of the semiconductor substrate and the second reflector is disposed between the first reflector and an emission side of the VCSEL. The first and second electrical contacts are disposed on a second side of the semiconductor substrate, opposite the first side, for mounting the VCSEL to a transparent substrate. The through-hole via electrically connects the second electrical contact to the second reflector.

A method of manufacturing a surface emitting laser includes: forming a mesa by performing etching on a lower reflector layer, an active layer, and an upper reflector layer; forming a current narrowing layer by oxidizing a part of the upper reflector layer; exposing a substrate by performing etching on the lower reflector layer, the active layer, and the upper reflector layer, using a chlorine-containing gas; cleaning the substrate; performing heat treatment on the substrate; forming an insulating film covering a surface of the substrate; forming an electrode on the lower reflector layer and the upper reflector layer; and performing heat treatment on the substrate, wherein a temperature in the first heat treatment is lower than a temperature in the forming the current narrowing layer.

A nitride semiconductor light-emitting device having high luminous efficiency is provided. A nitride semiconductor light-emitting device is provided with a nitride semiconductor substrate including a main surface having an off angle of 0.4 or larger with respect to a (0001) plane, a first semiconductor layer formed of an n-type or p-type nitride semiconductor formed on the main surface, a second semiconductor layer formed of a nitride semiconductor having In composition of 2% or higher formed on the first semiconductor layer, an active layer formed on the second semiconductor layer including a well layer formed of a nitride semiconductor having In composition higher than that of the second semiconductor layer and a barrier layer formed of a nitride semiconductor stacked therein, and a third semiconductor layer formed on the active layer having a conductivity type different from that of the first semiconductor layer.