摘要:
A multimode light generating module comprises an optical cavity and a light-receiving element. The optical cavity is constituted by a semiconductor optical amplification element, and an optical fiber having a grating. The optical fiber comprises a grating having an apodized periodic refractive index distribution, and the slope of the reflection spectrum in a longer wavelength region with respect to the peak wavelength λp is gentler than that in the shorter wavelength region therewith. The grating satisfies the relationship of 0.5 nm>λ0.2−λp>0.1 nm. Here, λ0.2 is defined by λ0.2h-λ0.2l, where λ0.2h is the longer one of two wavelengths exhibiting a relative reflectivity of 0.2 with respect to the maximum reflectivity, and λ0.2l is the shorter one of two wavelengths exhibiting a relative reflectivity of 0.2 with respect to the maximum reflectivity.
摘要:
There is disclosed a method of manufacturing an integrated circuit, comprising: the first step of growing a first epitaxial crystal on a compound semiconductor substrate, removing an unnecessary region of the first epitaxial crystal to form a residual portion, and covering the residual portion with a selective growth mask, the second step of growing a second epitaxial crystal on an exposed substrate portion, removing an unnecessary portion of the second epitaxial crystal to form a residual portion of the second epitaxial crystal, and covering the residual portion of the second epitaxial crystal with a selective growth mask, and third step of growing a third epitaxial crystal on an exposed substrate portion and removing an unnecessary region of the third epitaxial crystal, wherein the first to third epitaxial crystal form any one of a pin photodiode crystal, a heterojunction bipolar transistor crystal, and a high electron mobility transistor crystal, and are different from each other.
摘要:
A fiber grating laser module comprises a semiconductor optical amplifier and a grating fiber in which a Bragg grating is formed in the core. The semiconductor optical amplifier provides a wave guide in which the light is generated and amplified by the carrier injection, the light emitting facet and the light reflecting facet. The Bragg grating in the grating fiber and the light reflecting facet of the semiconductor amplifier forms an optical resonator. The subject of the invention is that the reflectance of the Bragg grating at the Bragg diffraction wavelength is greater than 60%.
摘要:
A semiconductor laser module includes a semiconductor laser having an active region between a light-reflecting surface and a light-exit surface thereof, and an optical fiber optically coupled to the semiconductor laser and including an optical fiber diffraction grating. The optical fiber diffraction grating selectively reflects light within a predetermined wavelength band. The wavelength band has a width larger than a wavelength interval of a longitudinal mode of light resonating between the light-reflecting surface and the light-exit surface.
摘要:
A main portion 10 of an optical module 1 includes a thermoelectric cooler 21, and a chip carrier 22b placed on the cooler 21. A semiconductor light-emitting device 31, a lens 32, photodetectors 33a, 33b, and an etalon 34 are directly or indirectly mounted on the chip carrier 22b. Supporting members 36a and 36b are also fixed on the chip carrier 22b. A roof 35 is supported by the supporting members 36a, 36b and positioned above the etalon 34. The roof 35, supporting members 36a, 36b and chip carrier 22b are maintained at substantially equal temperatures by the cooler 21. As a result, the temperature of the etalon 34 is stabilized, and therefore the variation in the lock wavelength is suppressed.
摘要:
In an opto-electronic integrated circuit of the present invention, in a first surface region of a semiconductor substrate, a pin-type photodiode is constituted on the basis of a photodiode layer formed on a first transistor layer. In a second surface region of the semiconductor substrate, a heterojunction bipolar transistor is constituted on the basis of only a second transistor layer separated form the first transistor layer. Since a plurality of heterojunction bipolar transistors are normally integrated for one pin-type photodiode, the thickness of the heterojunction bipolar transistors larger in number than the pin-type photodiode is set regardless of the thickness of the pin-type photodiode. The thickness of a high-resistance layer in the pin-type photodiode is set with an increased degree of freedom. When the first surface region of the semiconductor substrate is the inner region of a recessed step portion, and the second surface region of the semiconductor substrate is the outer region of the recessed step portion, a difference in thickness between the heterojunction bipolar transistor and the pin-type photodiode is absorbed by the depth of the recessed step portion. For this reason, the pin-type photodiode and the heterojunction bipolar transistor are formed to have almost the same surface level.
摘要:
A light receiving module and its manufacturing method of an excellent structure which can make a good and uniform optical couple between an optical fiber and a light receiving element, and can improve its productivity. The light receiving module comprises a semiconductor substrate, a light receiving element mounted on a surface of the semiconductor substrate, a groove formed on a back surface of the semiconductor substrate, an inclined face in the back surface side facing the light receiving element, and an optical fiber fixed in the groove. A transmitted light signal through the fiber is reflected by the inclined face. The inclined face is formed at a distal end of the optical fiber, at the closed end wall of the groove, or a side wall of a dimple arranged on the extension line of the groove. The reflected light is admitted to a light receiving face of the light receiving element, from the back surface side of the semiconductor substrate.
摘要:
Present invention is to provide a process for producing an opto-electronic integrated circuit comprising a field effect transistor as an electronic device and a photo-diode as an optical device both formed on an InP substrate,the field effect transistor comprising a high electron mobility transistor having:a GaInAs layer epitaxially grown in the InP substrate in a preset region thereof, a n-AlInAs layer epitaxially grown on the GaInAs layer, a gate electrode formed on the AlInAs layer, and a source electrode and a drain electrode formed on the AlInAs layer with the gate electrode therebetween, andthe photo-diode comprising a PIN photo-diode having:the GaInAs layer epitaxially grown on the InP substrate near the region of the field effect transistor simultaneously with the growth of that of the field effect transistor, the n-AlInAs layer epitaxially grown on the GaInAs layer simultaneously with the growth of that of the field effect transistor, a n-InP layer epitaxially grown on the n-AlInAs layer, an undoped GaInAs layer epitaxially grown on the n-InP layer in a preset region thereof, a p-GaInAs layer epitaxially grown on the undoped GaInAs layer, an anode electrode formed on the p-GaInAs layer, and a cathode electrode formed on the n-InP layer near the undoped GaInAs layer.
摘要:
A field effect transistor utilizing semiconductor hetero junction having a high mutual conductance, low noise, and a reduced source resistance, has a gallium indium arsenide mixed crystal semiconductor layer (23) providing a current path, low resistance indium phosphide layers formed on or under the gallium indium arsenide mixed crystal semiconductor layer (23) by ion-implantation for achieving the reduced source resistance, a source electrode (6), a gate electrode (5) and a drain electrode (7) which are formed on the surface of an uppermost aluminum indium arsenide mixed crystal semiconductor layer (24), an ion-implanted layer located at least in a region to form the reduced source resistance between the source electrode (6) and a two-dimensional electron layer (8) within the gallium indium arsenide mixed crystal semiconductor layer (23).
摘要:
The present invention provides a multimode semiconductor laser module. The module comprises a multimode laser element 34, an optical filter 54, a light-receiving element 52 and a temperature regulator 24. Multimode light from the laser element 34 is transmitted through the filter 54 and then detected by the light-receiving element 52. The output of the light-receiving element 52 changes according to the degree of overlap between the oscillation wavelength spectrum of the laser element 34 and the transmission wavelength region of the filter 54. The temperature regulator 24 modifies the oscillation wavelength region toward the desired region in response to the output of the light-receiving element 52. As a result, the oscillation wavelength region is stabilized.