Patent application number | Description | Published |
20080253422 | Surface emitting semiconductor laser - A surface emitting semiconductor laser comprises first and second distributed Bragg reflectors, an active layer and a junction region. The first distributed Bragg reflector includes first III-V compound semiconductor layers and second III-V compound semiconductor layers, and the first and second III-V compound semiconductor layers are alternately arranged. The second distributed Bragg reflector includes a first portion and a second portion. The first portion including third III-V compound semiconductor layers and fourth III-V compound semiconductor layers, and the third and fourth III-V compound semiconductor layers are alternately arranged. The second portion includes first insulating layers and second insulating layers, and the first and second insulating layers are alternately arranged. The active layer is provided between the first distributed Bragg reflector and the second distributed Bragg reflector. The active layer is made of III-V compound semiconductor. The first portion of the second distributed Bragg reflector is provided between the active layer and the second portion. The junction region includes a tunnel junction, and the junction region is provided between the active layer and the second distributed Bragg reflector. | 10-16-2008 |
20080285612 | Surface emitting semiconductor laser - In a surface emitting semiconductor laser, a first distributed Bragg reflector includes first and second semiconductor layers of a first conductive type, and the first and second semiconductor layers are alternately arranged. A second distributed Bragg reflector includes first and second portions, and the first and second portions are arranged in a direction of a predetermined axis. The first portion is made of semiconductor, and the second portion is made of dielectric. An active layer is provided on the first distributed Bragg reflector, and the first portion of the second distributed Bragg reflector is provided between the active layer and the second portion of the second distributed Bragg reflector. The first distributed Bragg reflector, the active layer and the second distributed Bragg reflector are sequentially arranged in the direction of the predetermined axis. A III-V compound semiconductor region is provided on the first distributed Bragg reflector so as to surround the first portion of the second distributed Bragg reflector. | 11-20-2008 |
20090080487 | Vertical cavity surface emitting laser diode (VCSEL) with enhanced emitting efficiency - A vertical cavity surface emitting laser diode (VCSEL) is disclosed, which reduces the light scattering by the step formed at the interface between the dielectric DBR and the semiconductor that reflects the mesa shape of the tunnel junction. The dielectric DBR of the invention includes a plurality of first films with relatively smaller refractive index and a plurality of second films with relatively larger refractive index. These first and second films are alternately stacked to each other to cause the periodic structure of the refractive indices. The VCSEL of the invention, different from the conventional device, provides the dielectric film with relatively larger refractive index that directly comes in contact with the semiconductor to set the node of the optical standing wave at the interface between the dielectric DBR and the semiconductor. | 03-26-2009 |
20090097518 | Vertical cavity surface emitting laser diode and a method for producing the same - A vertical cavity surface emitting laser diode (VCSEL) with a new structure is disclosed. The VCSEL of the invention provides the active layer, the first spacer layer, the tunnel junction, the second spacer layer burying the tunnel junction. Only the first spacer layer is ion-implanted to form a high-resistive region around the tunnel junction. The current injected into the second spacer layer is confined by the tunnel junction to reach the active layer, which reduces the increase of the parasitic resistance of the device. The high-resistive region around the tunnel junction reduces the parasitic capacitance of the device. | 04-16-2009 |
20090141766 | Surface emitting semiconductor laser - In a surface emitting semiconductor laser, the primary surface of a substrate includes first to third areas. The first and second areas are contiguous to each other, and the third area surrounds the first and second areas. A first DBR is provided on the substrate. An active layer is provided on the following: the first DBR; the first and second areas; and a boundary therebetween. A first semiconductor spacer layer is provided on the active layer. A second semiconductor spacer layer is provided on the first semiconductor spacer layer. The conductivity type of the first semiconductor spacer layer is different from that of the second semiconductor spacer layer. A tunnel junction region is on the first area and between the first and the second semiconductor spacer layers. The active layer, the first semiconductor spacer layer, the second semiconductor spacer layer, the tunnel junction region constitutes an optical cavity mesa, which includes low-resistance and high-resistance regions located on the first area and the second area, respectively. The low-resistance region includes the tunnel junction region. A second DBR is on the second semiconductor spacer layer and the first area. A first electrode is on the first and second areas and the boundary. | 06-04-2009 |
20090213892 | VCSEL WITH REDUCED LIGHT SCATTERING WITHIN OPTICAL CAVITY - A VCSEL with a structure able to reduce the scattering within the optical cavity and its manufacturing method are disclosed. The VCSEL of the present invention provides, on the semiconductor substrate, the first DBR, the active layer, the p-type spacer layer, the heavily doped p-type mesa, the heavily doped n-type layer, the first n-type spacer and the second DBR in this order. The heavily doped n-type layer, which is formed so as to cover the p-type spacer layer and the heavily doped p-type mesa, forms the tunnel junction with respect to the heavily doped p-type mesa. Because the height, which is appeared in the surface of the n-type spacer layer, reflects the height of the heavily doped p-type mesa and is comparatively small, the light scattering between the second DBR and the n-type spacer layer is suppressed. | 08-27-2009 |
20100014551 | VERTICAL CAVITY SURFACE EMITTING LASER - A VCSEL includes a GaAs substrate; a first semiconductor distributed Bragg reflector (DBR) disposed on the GaAs substrate and including a first part and a second part on the first part; a semiconductor mesa disposed on the first semiconductor DBR and including an active layer; and a second DBR on the semiconductor mesa. The first part is composed of an undoped semiconductor material. The second part includes third III-V compound semiconductor layers composed of a material containing indium and gallium as the group III element and phosphorus as the group V element and fourth III-V compound semiconductor layers composed of a material containing gallium as the group III element and arsenic as the group V element. The third III-V compound semiconductor layers and the fourth III-V compound semiconductor layers are doped with an n-type impurity. | 01-21-2010 |
20110164642 | LASER DIODE WITH RIDGE WAVEGUIDE STRUCTURE AND METHOD FOR MANUFACTURING THE SAME - An LD with an improved heat dissipating function in the edge regions is disclosed. The LD provides the core region including the active layer and extending whole of the substrate, and the ridge waveguide structure on the core region that extends in a direction along which the light generated in the active layer is guided. The ridge waveguide structure is buried by a thick resin layer in both sides thereof, but the resin layer is removed in the edge regions close to respective facets of the LD. | 07-07-2011 |
20120093190 | SEMICONDUCTOR LASER DEVICE AND METHOD FOR PRODUCING THE SAME - A semiconductor laser device includes a first semiconductor stack portion that includes a grating layer and an active layer provided on the grating layer. The grating layer has a first region and second region; a diffraction grating provided in the first region; a semiconductor ridge structure portion provided on the first semiconductor stack portion and extending in a first direction; and a pair of first trenches provided along both side faces of the semiconductor ridge structure portion with the first region of the grating layer being located between the trenches. The first trenches penetrate through the grating layer. The first region of the grating layer has an end extending in a second direction intersecting with the first direction. The end of the first region of the grating layer reaches a trench. | 04-19-2012 |
20120094408 | METHOD FOR PRODUCING SURFACE EMITTING SEMICONDUCTOR DEVICE - A method for producing a surface emitting semiconductor device includes a step of forming a semiconductor stacked structure including an active layer, a first semiconductor layer containing aluminum on the active layer, and a DBR portion, on the first semiconductor layer, to include alternating stacked second semiconductor layers and third semiconductor layers having different aluminum contents; a step of forming a mesa portion by etching the DBR portion and the first semiconductor layer; an oxidation step of oxidizing the first semiconductor layer from a side face of the mesa portion toward the inside of the mesa portion to form an annular oxidized region inside the first semiconductor layer; a first etching step of selectively etching an oxidized region formed in the DBR portion; and a second etching step of removing a peripheral portion of the DBR portion. | 04-19-2012 |
20120214265 | METHOD FOR FORMING COATING FILM ON FACET OF SEMICONDUCTOR OPTICAL DEVICE - The method includes the steps of preparing an epitaxial wafer by forming a multilayer semiconductor structure on a main surface of a substrate; forming stripe electrodes and bonding pads on the multilayer semiconductor structure with the bonding pads being respectively electrically connected to the stripe electrodes; forming a projection portion on the multilayer semiconductor structure; forming laser diode (LD) bars by cutting the epitaxial wafer; arranging the LD bars on a support surface such that a side surface thereof is oriented normal to the support surface, and disposing spacers between the LD bars; and forming a coating film on the side surface. The projection portion has a height, measured from the main surface of the substrate, greater than a height of the stripe electrodes. Furthermore, the laser diode bar has at least one projection portion. | 08-23-2012 |
20120224820 | SPOT-SIZE CONVERTER - A spot-size converter includes a cladding layer having a principal surface; a first core layer disposed on the principal surface and having a light input/output portion and a first transition portion having a width W | 09-06-2012 |
20150085292 | WAVELENGTH MONITOR - Provided are an optical element and a wavelength monitor capable of detecting a wavelength with high accuracy and at high speed while suppressing a size. The optical element includes: a branch waveguide section configured to branch an input light beam and generate two outputs routed via paths having mutually different optical path lengths; and an optical synthesis section configured to synthesize the two outputs and output two optical signals having different light intensities with regards to a wavelength of the input light beam and exhibiting a mutual phase difference. | 03-26-2015 |