Abstract:
A semiconductor device employs an epitaxial layer arrangement including a first ohmic contact layer and first modulation doped quantum well structure disposed above the first ohmic contact layer. The first ohmic contact layer has a first doping type, and the first modulation doped quantum well structure has a modulation doped layer of a second doping type. At least one isolation ion implant region is provided that extends through the first ohmic contact layer. The at least one isolation ion implant region can include oxygen ions. The at least one isolation ion implant region can define a region that is substantially free of charge carriers in order to reduce a characteristic capacitance of the device. A variety of high performance transistor devices (e.g., HFET and BICFETs) and optoelectronic devices can employ this device structure. Other aspects of wavelength-tunable microresonantors and related semiconductor fabrication methodologies are also described and claimed.
Abstract:
본 발명은 5Gbps 이상의 초고속 통신용의 레이저 다이오드 칩이 포함되는 TO can형의 초고속 통신용 광 모듈에 관한 것이다. 본 발명에 따른 초고속 통신용 광 모듈은 고속 통신용 광모듈에 있어서, 레이저 다이오드 칩에 신호를 전송하기 위한 고속 신호 전송용 기판, 고속 신호 전송용 선로 패턴이 형성된 상부 고속 신호 전송용 기판(210)과, 상부면이 도전성을 갖는 하부 고속 신호 전송용 기판(220)이 결합되어 이루어져, 단일 종단 임피던스 25ohm 또는 차동 종단 임피던스 50ohm을 가져 고속 통신이 가능하고, 고속 통신을 위한 레이저 다이오드 칩이 부착되는 기판의 높이가 0.4mm 정도가 되도록 하여 레이저 다이오드 칩과 렌즈 등의 광 결합을 용이하게 하며, 0.6mm 이하의 기판 폭으로 고속 전송 선로를 구현하여 TO can형의 좁은 실장 면적을 가지는 패키지에 효과적으로 내장되는 고속 신호 전송용 기판을 제공할 수 있다.
Abstract:
A VCSEL device having a mesa for generating laser light includes a centralized thermal containment area and a thermal discharge area surrounding the centralized thermal containment area. The device includes a thermal lensing structure for enhancing or controlling heat flow within the centralized thermal containment area and the thermal discharge area and creating and maintaining an index of refraction between the centralized thermal containment area and the thermal discharge area. The VCSEL device operates as a multimode device when driven at a first current in a continuous wave and the VCSEL device operates as a single mode device when driven at a second current at a pulse rate shorter than an overall thermal time constant of the VCSEL device.
Abstract:
The invention is applicable for use in conjunction with a light-emitting semiconductor structure that includes a semiconductor active region of a first conductivity type containing a quantum size region and having a first surface adjacent a semiconductor input region of a second conductivity type that is operative, upon application of electrical potentials with respect to the active and input regions, to produce light emission from the active region. A method is provided for enhancing operation of the light-emitting semiconductor structure, including the following steps: providing a semiconductor output region that includes a semiconductor auxiliary layer of the first conductivity type adjacent a second surface, which opposes the first surface of the active region, and providing the auxiliary layer as a semiconductor material having a diffusion length for minority carriers of the first conductivity type material that is substantially shorter than the diffusion length for minority carriers of the semiconductor material of the active region.
Abstract:
A method of operating a laser source comprising a single mode master laser (10) and a multimode VCSEL slave laser (20) is provided. According to the method, the spatial and spectral coupling of the single mode optical output of the master laser and a targed mode of the multimode optical resonator of the VCSEL slave laser are controlled to progress from a relatively mode-matched spatial and spectral coupling to a relatively mismatched spatial and spectral coupling to facilitate optically injected mode locking in the laser source. Further, a laser source is provided comprising a single mode master laser and a multimode VCSEL slave laser. The single mode master laser comprises a wavelength tuning element (60) and a spatial tuning element (15) that facilitate optically injected mode locking in the laser source spectrally mismatched optical seeding results in an enhanced modulation bandwidth of the VCSEL slave laser.
Abstract:
A transmission mechanism for transmitting an electrical signal from the output stage of an electro-optic transducer driver to an electro-optic transducer. The transmission mechanism includes the electro-optic transducer, the electro-optic transducer driver and a termination resistor. A first node of the termination resistor is coupled to the first differential input terminal of the electro-optic transducer. A second node of the termination resistor is coupled to the first output node of the electro-optic transducer driver. In addition, a second differential input terminal of the electro-optic transducer is coupled to a second output node of the electro-optic transducer driver. Such connections provide for a first DC path from the first differential input terminal of the electro-optic transducer to the second electro-optic transducer driver output node and a second DC path from the first node of the termination resistor to first electro-optic transducer driver output node.
Abstract:
A fast current-controlled polarization switching VCSEL with two independent intracavity p-contact electrodes and two independent intra-cavity n-contact electrodes positioned along the four sides of the symmetric aperture such that there are two independent p- and n- contact pairs placed on opposite sides of the aperture in a non-overlapping configuration. The anisotropy resulting from the unidirectional current flow causes the light output to be polarized perpendicular to the direction of current flow. A VCSEL driver circuit switches the polarization state of the output light by using the two orthogonal pairs of non-overlapping intra-cavity contacted electrodes to change the direction of current flow into the VCSEL aperture by 90 degrees.
Abstract:
An RF-lightwave transmitter (10) performs successive conversions of an information-bearing input signal in order to generate an output signal suitable for transmission in a wireless communications system. The transmitter (10) includes a high-efficiency FM laser (22) connected to a FM discriminator (24). In operation, the laser (22) converts an RF signal into a frequency-modulated optical signal, and the discriminator (24) converts this signal into an amplitude-modulated optical signal. The discriminator (24) performs its conversion using a high slope-efficiency linear transfer function which ensures that the AM optical signal varies in accordance with a desired operational performance.