Abstract:
An optical transceiver for detecting an incoming light beam and for transmitting an outgoing light beam along a common optical axis is provided. Such an optical transceiver provides a compact optical transceiver that is suitable for a wide variety of applications.
Abstract:
Disclosed are methods for providing wafer parasitic current control to a semiconductor wafer (1240) having a substrate (1240), at least one active layer (1240) and at least one surface layer (1240), Current control can be achieved through the formation of patterns ( 1240) surrounding contacts (1215), said patterns (1240) including insulating implants and/or sacrificial layers formed between active devices represented by said contacts (1215). Current flows through active regions (1260) associated with said contacts (1215) and active devices. Methods of and systems for wafer level burn-in (WLBI) of semiconductor devices are also disclosed. Current control at the wafer level is important when using WLBI methods and systems.
Abstract:
Methods of conducting wafer level burn-in (WLBI) of semiconductor devices are presented wherein systems are provided having at least two electrodes (210, 215). Electrical bias (920) and/or thermal power (925) is applied on each side of a wafer (100) having back and front electrical contacts for semiconductor devices borne by the wafer. A pliable conductive layer (910) is described for supplying pins on the device side of a wafer with electrical contact and/or also for providing protection to the wafer from mechanical pressure being applied to its surfaces. Use of a cooling system (950) is also described for enabling the application of a uniform temperature to a wafer undergoing burn-in. Wafer level burn-in is performed by applying electrical and physical contact (915) using an upper contact plate to individual contacts for the semiconductor devices ; applying electrical and physical contact using a lower contact plate (910) to a substrate surface of said semiconductor wafer ; providing electrical power (920) to said semiconductor devices through said upper and lower second contact plates from a power source coupled to said upper and lower contacts plates ; monitoring and controlling electrical power (935) to said semiconductor devices for a period in accordance with a specified burn-in criteria ; removing electrical power at completion of said period (955) ; and removing electrical and physical contact to said semiconductor wafer (965).
Abstract:
A method and apparatus for fabricating a metamorphic long-wavelength, high-speed photodiode, wherein a buffer layer matching a substrate lattice constant is formed at normal growth temperatures and a thin grading region which grades past the desired lattice constant is configured at a low temperature. A reverse grade back is performed to match a desired lattice constant. Thereafter, a thick layer is formed thereon, based on the desired lattice constant. Annealing can then occur to isolate dislocated mater5ial in a grading layer and a reverse grading layer. Thereon a strained layer superlattice substrate is created upon which a high-speed photodiode can be formed. Implant or diffusion layers grown in dopants can be formed based on materials, such as Be, Mg, C, Te, Si, Se, Zn, or others a metal layer can be formed over a cap above a P+ region situated directly over an N-active region. The active region also includes a p-doped region. The high-speed photodiode can thus be formed utilizing GaAs, or other substrate material, such as germanium and silicon.
Abstract:
Methods and apparatus for monitoring the power level of a multi-wavelength optical signal are provided, making use of a light detector comprising a first and a second absorbing layer having both the same conductivity type, and intermediate layer of a second conductivity type and means for providing an indication of a change in power of the first and/or the second wavelength of light as measured by the respective absorbing layers. Also provided are methods and apparatus for adjusting the power level of selected optical emitters to compensate for the changes in power levels. An optoelectronic transmitter for receiving electrical input signals and transmitting corresponding optical output signals in a common light beam comprises electrical modulators, optoelectronic emitters, an optical combiner, an optoelectronic detector, means for separating the signals detected by the detector, and means for adjusting the power of the optoelectronic emitters.
Abstract:
Disclosed are methods for providing wafer parasitic current control to a semiconductor wafer (1500) having a substrate (1520), at least one active layer (1565) and a surface layer (1510), and electrical contacts (1515) formed on said surface layer (1510). Current control can be achieved with the formation of trenches (1525) around electrical contacts, where electrical contacts and associated layers define an electronic device. Insulating implants (1530) can be placed into trenches (1525) and/or sacrificial layers (1540) can be formed between electronic contacts (1515). Trenches control current by promoting current flow within active (e.g., conductive) regions (1560) and impeding current flow through inactive (e.g., nonconductive) regions (1550). Methods of and systems for wafer level burn-in (WLBI) of semiconductor devices are also disclosed. Current control at the wafer level is important when using WLBI methods and systems.
Abstract:
A multiple laser optical sensing system and method for detecting target characteristics are disclosed. The system includes a laser source with at least two emission apertures from which laser signals are emitted. The system also includes at least one detector, which is operationally responsive to the laser source. Finally, the system includes a microprocessor that is operationally coupled to the detector(s). In operation, the laser source emits into an environment at least two laser signals, one from each emission aperture. The detector detects the laser signals after the signals pass through the environment, which is occupied by a target, and the microprocessor determines target characteristics based on the laser signals received by the detectors.
Abstract:
A system and method for VCSEL (vertical cavity surface emitting laser) polarization control is disclosed, including methods and apparatus comprising a component package (302, 304) having self-aligning features (316, 318), for indicating an alignment axis (320, 322), and upper surface aperture (314) formed therein, a vertical cavity surface emitting laser device (308) having two emission polarizations (204) normal to one another, disposed within the component package and aligned such that each emission polarization is at about 45 degrees with respect to the alignment axis, and a linear polarization element (400, 402, 406) having a polarization direction (206), spanning the aperture and disposed such that the polarization direction is parallel to the alignment axis.
Abstract:
A VCSEL (100) having a metallic heat spreading layer (128) adjacent a semiconductor buffer layer (122) containing an insulating structure (124). The heat spreading layer (128) includes an opening (130) that enables light emitted by an active region (120) to reflect from a distributed Bragg reflector (DBR) top mirror (132) located above the heat spreading layer (128). A substrate (112) is below the active region (120). A lower contact (114) provides electrical current to that substrate (112). The lower contact (114) includes an opening (115) that enables light emitted from the active region (120) to reflect from a distributed Bragg reflector (DBR) lower mirror (116). Beneficially, the substrate (112) includes a slot that enables light to pass through an opening in the lower contact (114). That slot acts as an alignment structure that enables optical alignment of an external feature to the VCSEL (100).
Abstract:
Disclosed are methods for providing wafer photonic flow control to a semiconductor wafer (1700) having a substrate (1720), at least one active layer (1765) and at least one surface layer (1710). Photonic flow control can be achieved through the formation of trenches (1725) and/or insulating implants (1730) formed in said wafer (1700), whereby active regions (1760) are defined by trenches (1725) that operate as nonconductive areas (1750). Methods of and systems for wafer level burn-in (WLBI) of semiconductor devices are also disclosed. Photonic flow control at the wafer level is important when using WLBI methods and systems.