Abstract: A method for fabricating a Mach-Zehnder modulator includes: preparing a substrate product having a waveguide mesa, an embedding resin body and an inorganic insulator, the waveguide mesa being disposed on a supporting base, the inorganic insulator covering the embedding resin body to separate the embedding resin body from the waveguide mesa, the waveguide mesa having top and side faces covered with the inorganic insulator, and the embedding resin body embedding the side face of the waveguide mesa; forming an opening in the inorganic insulator by etching to form an inorganic insulating region, the opening reaching the top face of the waveguide mesa, the inorganic insulating region covering the embedding resin body and the side face of the inorganic insulator; and forming an ohmic electrode in the opening to make contact with the top face of the mesa, the inorganic insulating region separating the ohmic electrode from the embedding resin body.

Abstract: A method for fabricating a light receiving device includes: preparing a first substrate product which includes a semiconductor region having a common semiconductor layer, a first semiconductor laminate for a photodiode, a second semiconductor laminate for a waveguide, and a butt-joint between the first semiconductor laminate and the second semiconductor laminate, the first laminate and the second semiconductor laminate being disposed on the common semiconductor layer; etching the first substrate product with a first mask to form a second substrate product having a photodiode mesa structure produced from the first semiconductor laminate and a preliminary mesa structure produced from the second semiconductor laminate; etching the second substrate product with the first mask and a second mask, formed on the photodiode mesa structure; to produce a waveguide mesa structure from the preliminary mesa structure, and the waveguide mesa structure having a height larger than that of the preliminary mesa structure.

Abstract: A method for fabricating a Mach-Zehnder modulator includes: preparing a substrate product having a waveguide mesa, an embedding resin body and an inorganic insulator, the waveguide mesa being disposed on a supporting base, the inorganic insulator covering the embedding resin body to separate the embedding resin body from the waveguide mesa, the waveguide mesa having top and side faces covered with the inorganic insulator, and the embedding resin body embedding the side face of the waveguide mesa; forming an opening in the inorganic insulator by etching to form an inorganic insulating region, the opening reaching the top face of the waveguide mesa, the inorganic insulating region covering the embedding resin body and the side face of the inorganic insulator; and forming an ohmic electrode in the opening to make contact with the top face of the mesa, the inorganic insulating region separating the ohmic electrode from the embedding resin body.

Abstract: A method for fabricating a Mach-Zehnder modulator includes: forming a resin body embedding a semiconductor mesa for an arm waveguide, the resin body having an opening on an upper face of the semiconductor mesa; forming an electrode on the semiconductor mesa and the resin body, the electrode being in contact with the upper face of the semiconductor mesa through the opening of the resin body; forming an inorganic insulating protective layer on the electrode and the resin body, the inorganic insulating protective layer having an arrangement of multiple first openings therethrough to the electrode; and forming a metal body on the inorganic insulating protective layer and the electrode, the metal body being in contact with the electrode through the multiple first openings of the inorganic insulating protective layer.

Abstract: A semiconductor optical element is disclosed. The semiconductor optical element includes: a mesa-shaped optical waveguide formed on a substrate; a modulation electrode formed on the optical waveguide; a first resin layer that buries side surfaces of the optical waveguide; a bonding pad formed on the first resin layer; and a connecting wiring line that connects the modulation electrode and the bonding pad. In the semiconductor optical element, side surfaces of the bonding pad are partially covered with a second resin layer provided on the first resin layer, and the connecting wiring line extends on the second resin layer.

Abstract: A Mach-Zehnder modulator includes: a semiconductor structure having a first waveguide portion, a second waveguide portion, and a third waveguide portion, which are disposed on the first area, the second area, and the third area of a principal surface of substrate, respectively; an embedding resin body having an opening on the first waveguide portion; an ohmic electrode including a first ohmic electrode portion connected to the first waveguide portion through the opening of the embedding resin body, and a second ohmic electrode portion disposed on the embedding resin body in the second area; and a conductor including a first conductive portion extending along the first ohmic electrode portion, and a second conductive portion disposed on the embedding resin body and having a width greater than that of the second ohmic electrode portion, the embedding resin body having a groove extending along an edge of the second ohmic electrode portion.

Abstract: A method for fabricating a light receiving device includes: preparing a first substrate product which includes a semiconductor region having a common semiconductor layer, a first semiconductor laminate for a photodiode, a second semiconductor laminate for a waveguide, and a butt-joint between the first semiconductor laminate and the second semiconductor laminate, the first laminate and the second semiconductor laminate being disposed on the common semiconductor layer; etching the first substrate product with a first mask to form a second substrate product having a photodiode mesa structure produced from the first semiconductor laminate and a preliminary mesa structure produced from the second semiconductor laminate; etching the second substrate product with the first mask and a second mask, formed on the photodiode mesa structure; to produce a waveguide mesa structure from the preliminary mesa structure, and the waveguide mesa structure having a height larger than that of the preliminary mesa structure.

Abstract: A semiconductor optical element is disclosed. The semiconductor optical element includes: a mesa-shaped optical waveguide formed on a substrate; a modulation electrode formed on the optical waveguide; a first resin layer that buries side surfaces of the optical waveguide; a bonding pad formed on the first resin layer; and a connecting wiring line that connects the modulation electrode and the bonding pad. In the semiconductor optical element, side surfaces of the bonding pad are partially covered with a second resin layer provided on the first resin layer, and the connecting wiring line extends on the second resin layer.

Abstract: A method for fabricating a Mach-Zehnder modulator includes: forming a resin body embedding a semiconductor mesa for an arm waveguide, the resin body having an opening on an upper face of the semiconductor mesa; forming an electrode on the semiconductor mesa and the resin body, the electrode being in contact with the upper face of the semiconductor mesa through the opening of the resin body; forming an inorganic insulating protective layer on the electrode and the resin body, the inorganic insulating protective layer having multiple first openings disposed on the electrode and the upper face of the semiconductor mesa; and forming a metal body on the inorganic insulating protective layer and the electrode, the metal body being in contact with the electrode through the multiple first openings of the inorganic insulating protective layer.

Abstract: A Mach-Zehnder modulator includes: a semiconductor structure having a first waveguide portion, a second waveguide portion, and a third waveguide portion, which are disposed on the first area, the second area, and the third area of a principal surface of substrate, respectively; an embedding resin body having an opening on the first waveguide portion; an ohmic electrode including a first ohmic electrode portion connected to the first waveguide portion through the opening of the embedding resin body, and a second ohmic electrode portion disposed on the embedding resin body in the second area; and a conductor including a first conductive portion extending along the first ohmic electrode portion, and a second conductive portion disposed on the embedding resin body and having a width greater than that of the second ohmic electrode portion, the embedding resin body having a groove extending along an edge of the second ohmic electrode portion.

Abstract: A Mach-Zehnder modulator comprises first to third semiconductor structures provided on first to third areas of a primary surface of a conductive semiconductor region, respectively. The second semiconductor structure includes a semiconductor laminate and a first contact portion thereon. The third semiconductor structure includes the semiconductor laminate and a second contact portion thereon. The first and second contact portions constitute a contact layer. The second semiconductor structure has first and second waveguide sides. The first contact portion has an edge which terminates the contact layer and extends in a direction of a first reference plane on the top of the semiconductor laminate to reach the first waveguide side. The first reference plane and a top of the second semiconductor structure intersect with each other to define a line of intersection obliquely-crossed with an upper edge of the first waveguide side at a first angle different from a right angle.

Abstract: A modulator including: a Mach-Zehnder modulator that includes an optical waveguide disposed on a substrate, the optical waveguide including an electrode thereon; a resin layer disposed on the substrate, the resin layer embedding the optical waveguide, the resin layer having a groove arranged besides the optical waveguide; a termination resistor disposed on the substrate in the groove of the resin layer; and a first wiring disposed on the resin layer, the first wiring being connected to the termination resistor and the electrode of the optical waveguide.

Abstract: An optical semiconductor device including: a substrate having a principal surface; first and second optical waveguides disposed on the principal surface of the substrate, the first and second optical waveguides extending in a first direction, the second optical waveguide being arranged adjacent to the first optical waveguide in a second direction intersecting with the first direction; first and second signal electrodes disposed on the first and second optical waveguides; a resistor disposed on the principal surface, the resistor being arranged between the first optical waveguide and the second optical waveguide, the resistor being electrically connected to the first signal electrode and the second signal electrode; a resin layer disposed on the principal surface, top surfaces of the first and second signal electrodes, and the resistor; and a capacitor disposed on the resin layer, the capacitor being electrically connected to the resistor through an opening of the resin layer.

Abstract: An electrostatic chuck device including: a plurality of adsorption areas having an electrode generating electrostatic attractive force; and a control portion controlling the electrostatic attractive force against each of the plurality of the adsorption areas independently of other adsorption areas.

Abstract: A semiconductor optical modulator includes a substrate having a principal surface; a waveguide disposed on the principal surface of the substrate, the waveguide extending in a first direction; a first electrode disposed on the waveguide, the first electrode being in contact with an upper surface of the waveguide; a first wiring connected to the first electrode, the first wiring extending in a second direction intersecting the first direction; a build-up portion connected to the first wiring; a second wiring connected to the build-up portion, the second wiring extending in a plane parallel to the principal surface of the substrate; and a resin layer disposed on the substrate, the resin layer embedding the first wiring and the build-up portion. The build-up portion extends along a third direction, the third direction intersecting perpendicularly to the principal surface of the substrate. The second wiring is disposed on the resin layer.

Abstract: A Mach-Zehnder modulator comprises first to third semiconductor structures provided on first to third areas of a primary surface of a conductive semiconductor region, respectively. The second semiconductor structure includes a semiconductor laminate and a first contact portion thereon. The third semiconductor structure includes the semiconductor laminate and a second contact portion thereon. The first and second contact portions constitute a contact layer. The second semiconductor structure has first and second waveguide sides. The first contact portion has an edge which terminates the contact layer and extends in a direction of a first reference plane on the top of the semiconductor laminate to reach the first waveguide side. The first reference plane and a top of the second semiconductor structure intersect with each other to define a line of intersection obliquely-crossed with an upper edge of the first waveguide side at a first angle different from a right angle.

Abstract: A method for producing optical semiconductor devices includes: forming a stacked semiconductor layer on a device substrate to provide an epitaxial substrate having a size corresponding to a section arrangement; forming, on the epitaxial substrate, a mask having a pattern for a semiconductor mesa and for a trench of at least one optical semiconductor device, a width of the trench in the pattern being determined according to a trench width map in which trench width is based upon an in-plane distribution of the thickness of a resin layer of the at least one device, and upon a correlation between the thickness of the resin layer and the trench width; forming a trench structure including the semiconductor mesa and the trench by etching the stacked semiconductor layer using the mask; forming a resin layer on the trench structure; and forming an opening on the semiconductor mesa by etching the resin layer.

Abstract: A method for producing a semiconductor optical device includes the steps of forming first and second optical waveguides; forming a first resin layer on the first and the second optical waveguides; forming an opening in the first resin layer; forming a first electrode in the opening; forming a second resin layer on the first electrode and the first resin layer; forming a groove in the second resin layer on the first electrode; forming a second electrode on the second resin layer, a side surface of the groove, and the top surface of the first electrode; and forming a third electrode on the second electrode. The second and third electrodes have a region in which the second and third electrodes pass over the second optical waveguide, and, in the region, the first and second resin layers are disposed between the second electrode and the second optical waveguide.

Abstract: A method for manufacturing a semiconductor modulator includes the steps of preparing a substrate having a main surface including first and second areas; forming a stacked semiconductor layer on the main surface; forming an optical waveguide mesa by etching the stacked semiconductor layer using a mask, the optical waveguide mesa including an optical modulation portion; applying a resin on a top surface and a side surface of the optical waveguide mesa and on the substrate; forming a first opening in the resin on the second area of the substrate; forming an underlayer structure on the second area of the substrate in contact with the substrate; and forming a pad electrode on the underlayer structure in contact with the underlayer structure through the first opening of the resin. The underlayer structure includes an insulating layer made of a dielectric material.

Abstract: A method for manufacturing a semiconductor optical waveguide device includes the steps of forming a waveguide mesa having first and second portions by etching a stacked semiconductor layer through a first mask; forming a dummy buried region embedding a top surface and side surfaces of the waveguide mesa; forming a second mask on the dummy buried region, the second mask having an opening on the first portion and having a pattern on the second portion; forming a third mask having an opening that reaches a top surface of the first portion, the third mask including a dummy buried mask formed by etching the dummy buried region through the second mask; forming an upper mesa by etching the waveguide mesa through the third mask; and after removing the third mask, forming a lower mesa by etching the stacked semiconductor layer, the lower mesa having a greater width than that of the upper mesa.