摘要:
A multilayered structure array has narrow pitches by making thinner coatings for insulating internal electrode layers from side electrodes and the productivity of the multilayered structure array is improved. The multilayered structure includes: a first internal electrode layer; a piezoelectric layer formed on the first internal electrode layer; a second internal electrode layer formed on the piezoelectric layer; a first coating formed on an end surface of the first internal electrode layer in a first side surface region of the multilayered structure and containing one of metal oxide, metal nitride, metal fluoride and metal sulfide in at least one part thereof; and a second coating formed on an end surface of the second internal electrode layer in a second side surface region of the multilayered structure and containing one of metal oxide, metal nitride, metal fluoride and metal sulfide in at least one part thereof.
摘要:
An ultrasonic transducer in which electrodes can be easily and positively joined to a multiplicity of micro-fabricated vibrators and electric wiring can be easily and positively provided. The ultrasonic transducer has a vibrator arrangement having vibrators provided in a predetermined arrangement, each vibrator having first and second electrodes; an interlayer board for holding the vibrator arrangement in which through-holes are respectively formed in positions corresponding to the second electrodes of the vibrators; and a wiring board having a plurality of electrodes electrically connected to the second electrodes of the vibrators through the through-holes formed in the interlayer board, respectively.
摘要:
In a process for producing a substrate for use in a semiconductor element: a porous anodic alumina film having a great number of minute pores is formed on a surface of a base substrate; the surface of the base substrate is etched by using the porous anodic alumina film as a mask so as to form a great number of pits on the surface of the base substrate; the porous anodic alumina film is removed; and a GaN layer is formed on the surface of the base substrate by crystal growth.
摘要:
In a process for producing a semiconductor light emitting device, first, a lamination including an active zone, cladding layers, and a current confinement layer is formed. Then, a near-edge portion of the lamination having a stripe width is removed so as to produce a first space, and a second near-edge portion located under the first space and a stripe portion of the lamination being located inside the first space and having the stripe width are concurrently removed so that a second space is produced, and cross sections of the active layer and the current confinement layer are exposed in the second space. Finally, the first and second spaces are filled with a regrowth layer so that a dopant to the regrowth layer is diffused into a near-edge region of the remaining portion of the active layer.
摘要:
By providing an area where an Au film 28b is removed and a Ti film 28a is exposed along the plane tangent to the side where the p-n junction of a semiconductor chip is exposed, sticking of the Au film 28b to the chip side or protruding of the film as a flash from the side is prevented, which normally provides a starting place for creep of a solder 42 on the chip side, which in turn causes p-n junction short-circuiting when dividing of chips.
摘要:
An n-GaAs buffer layer, an n-AlGaAs lower cladding layer, an n- or i-InGaP lower optical waveguide layer, an InGaAsP quantum cell active layer, a p- or i-InGaP upper optical waveguide layer, a p-AlGaAs first upper cladding layer, a p- or i-InGaP etch-stopping layer, a p-AlGaAs second upper cladding layer, and a p-GaAs contact layer, are grown upon an n-GaAs substrate. A photoresist is coated on the wafer, and two grooves are formed by etching. Then, the photoresist on the perimeter of the device is removed and the contact layer is selectively etched. Next, the photoresist is lifted off. A SiO2 film is formed on the entire surface. After a window is formed in a portion of the SiO2 film corresponding to a ridge portion, a p-electrode is formed on a region of the SiO2 film other than the device perimeter.
摘要:
An n-GaAs buffer layer, an n-AlGaAs lower cladding layer, an n- or i-InGaP lower optical waveguide layer, an InGaAsP quantum cell active layer, a p- or i-InGaP upper optical waveguide layer, a p-AlGaAs first upper cladding layer, a p- or i-InGaP etch-stopping layer, a p-AlGaAs second upper cladding layer, and a p-GaAs contact layer, are grown upon an n-GaAs substrate. A photoresist is coated on the wafer, and two grooves are formed by etching. Then, the photoresist on the perimeter of the device is removed and the contact layer is selectively etched. Next, the photoresist is lifted off. A SiO2 film is formed on the entire surface. After a window is formed in a portion of the SiO2 film corresponding to a ridge portion, a p-electrode is formed on a region of the SiO2 film other than the device perimeter.
摘要:
In a process for producing a semiconductor light emitting device, first, a lamination including an active zone, cladding layers, and a current confinement layer is formed. Then, a near-edge portion of the lamination having a stripe width is removed so as to produce a first space, and a second near-edge portion located under the first space and a stripe portion of the lamination being located inside the first space and having the stripe width are concurrently removed so that a second space is produced, and cross sections of the active layer and the current confinement layer are exposed in the second space. Finally, the first and second spaces are filled with a regrowth layer so that a dopant to the regrowth layer is diffused into a near-edge region of the remaining portion of the active layer.
摘要:
A semiconductor laser device improves reliability during high-power oscillation. An n-type GaAs buffer layer, an n-type In0.48Ga0.52P lower cladding layer, an n-type or i-type Inx1Ga1−x1As1−y1Py1 optical waveguide layer, an i-type GaAs1−y2Py2 tensile-strain barrier layer, an Inx3Ga1−3As1−y3Py3 compressive-strain quantum-well active layer, an i-type GaAs1−y2Py2 tensile-strain barrier layer, a p-type or i-type Inx1Ga1−x1As1−y1Py1 upper optical waveguide layer, a p-type In0.48Ga0.52P first upper cladding layer, a GaAs etching stop layer, a p-type In0.48Ga0.52P second upper cladding layer, and a p-type GaAs contact layer are grown on a plane of an n-type GaAs substrate. Two ridge trenches are formed on the resultant structure, and current non-injection regions are formed by removing the p-type GaAs contact layer in portions extending inwardly by 30 &mgr;m from cleavage positions of edge facets of the resonator on a top face of a ridge portion between the ridge trenches.
摘要:
An ultrasonic transducer (20) is enclosed by a cap (19). Inside of the cap (19) is filled with liquid paraffin (25). The liquid paraffin (25) has a maximum molecular weight M1 of 520 ≦M1≦1400, a peak top molecular weight M2 of 230≦M2≦380, and a kinematic viscosity S (mm2/s) of 4≦S≦12.5 at 40° C. This liquid paraffin (25) achieves deeper penetration of the ultrasonic waves into biological tissues and higher receiver sensitivity to the echoes of the ultrasonic waves across a broad frequency range.