Abstract: A laser processing fixture is formed to allow for facet processing of cleaved laser bars, either individually, or allowing for multiple bars to be processed simultaneously. The fixture holds the bars at a precisely-controlled distance with respect to a predefined reference plane, and holds the bars rigidly enough so as to minimize the possibility of vibration, but not so forcefully as to cause damage. The fixture comprises a fixed jaw and a movable jaw, with a pair of spaced-apart support members extending between the jaws. One or more laser bars may then be positioned between the jaws such that the front and rear facets will be exposed above and below the jaws. Therefore, each facet may be processed without unloading and re-loading the bars in the fixture. The support members, which may comprise a pair of wires, are spaced a sufficient distance so as to be disposed beyond the location of any active device region.

Abstract: A self-modulated solid state laser comprises an intracavity optical waveguide that supports a multiplicity of lasing filaments each at a different optical frequency. At least two of the filaments temporally beat with one another so as to modulate the intensity of the laser output. In accordance with one embodiment of our invention, the waveguide supports a multiplicity of transverse modes, and the laser includes a mode mixing mechanism that mixes the energy of at least two pairs of the modes, each coupled pair generating a separate filament. In an illustrative embodiment, the filaments are mode locked and the laser output is modulated at a frequency on the order of 1 THz.

Abstract: Optical detection apparatus comprises a solid state laser having an intracavity optical waveguide that supports a lasing filament and operates in one of two states: (1) in a first state, the filament is fixed in one of two orientations, and (2) in a second state, the filament may be induced to switch or oscillate between the two orientations, or it may be suppressed altogether. At least one feature is located on the output facet off-center with respect to the waveguide cross-section in order to provide a preferred orientation for the filament. In one embodiment, a single feature is located off-center and optical radiation of one intensity is injected through the facet feature, thereby causing the laser to operate in one of its states, whereas injected radiation of another intensity causes the laser to operate in the other of its states. The injected radiation may be radiation emitted by the laser that is reflected by an object (e.g.

Abstract: An improved anvil tool for use in laser bar or wafer cleaving comprises a relatively small cross section such that the anvil does not overhang the device edges in any direction. In one embodiment, the surface of the tool contacting the laser wafer or bar is compliant and contains a laterally disposed slit that aligns with the scribe mark on the top surface of the material to be cleaved. The anvil may be formed as a columnar tool or as a film deposited on a substrate. The compliant surface may be removable and in a preferred embodiment may comprise a continuous feed membrane tape so that a “clean” surface is used for each subsequent cleave operation.

Abstract: Fabrication of an optoelectronic device is enhanced by using a focused ion beam to prepare one or more of the device's facet surfaces. In particular, a facet may be oriented at a nearly arbitrary angled with respect to the waveguide within the device by controlling the orientation between the focused ion beam source and the device waveguide. Such facets are useful as antireflection and refractive beamsteering surfaces.

Abstract: An incrementally continuous cleaving system allows for sequential flow of "material-to-be-cleaved" through a cleaving apparatus. In particular, a continuous feed tape membrane is used to support sequentially loaded optical bars (or, perhaps, wafers) that are then transported into a cleaving apparatus. The tape is advanced in small increments so that individual cleaving operations are performed at each scribe mark location on the top surface of the optical material. A vacuum pen (assisted by a detach pin) is then used to remove the cleaved section from the cleaving system. A conventional pick-and-place device may be used in the first instance to continuously load the bars (or wafers) onto the tape membrane.

Abstract: A cleaving apparatus for separating a wafer (or bar) bar of optical devices into separate bars (or individual optical devices) comprises a relatively thin wire, preferably tungsten. The wire is forced against the underside of the bar directly underneath the location of a top side scribe mark. The wire, having a highly uniform, well-controlled radius of curvature, induces a known, reproducible stress through the body of the bar and nucleates a cleavage crack under the scribe mark. A force applied to the top surface of the bar will allow the cleaving crack to propagate cleanly along a single crystal surface through the depth of the bar to the location of the wire.

Abstract: A semiconductor optical device is formed to include a substrate-side dielectric barrier layer in the area where the substrate and facet meet. The dielectric is deposited on the substrate surface prior to cleaving of the facet and results in reducing the defects along the facet. The dielectric material also serves as a substrate-side "anchor" for the dielectric deposited on the facet, reducing the incidence of delamination of the dielectric coating from the facet.