Agilent Technologies, Inc.

Leland Stanford Junior University

Fred Sugihwo

Rene P Helbing

Annette Claire Grot

Sandeep Raj Bahl

James S Harris, Jr

Virginia Robbins

Yu-Min Houng

Optical systems that include optical fiber splices are provided. Such an optical system includes first and second optical fibers, each of which has an end surface and a side surface adjacent to the end surface. An adhesive joins the end surface of the first optical fiber to the end surface of the second optical fiber. Additionally, at least a portion of the end surface of the first optical fiber exhibits a wettability for the adhesive that is higher than a wettability for the adhesive exhibited by at least a portion of the side surface of the first optical fiber. Methods and other systems also are provided.

Optical fiber splicing using surface tension

Systems and methods of manufacturing etchable heterojunction interfaces and etched heterojunction structures are described. A bottom layer is deposited on a substrate, a transition etch layer is deposited over the bottom layer, and a top layer is deposited over the transition etch layer. The transition etch layer substantially prevents the bottom layer and the top layer from forming a material characterized by a composition substantially different than the bottom layer and a substantially non-selective etchability with respect to the bottom layer. By tailoring the structure of the heterojunction interface to respond to heterojunction etching processes with greater predictability and control, the transition etch layer enhances the robustness of previously unreliable heterojunction device manufacturing processes. The transition etch layer enables one or more vias to be etched down to the top surface of the bottom layer in a reliable and repeatable manner. In particular, because the transition etch layer enables use of an etchant that is substantially selective with respect to the bottom layer, the thickness of critical device layers may be determined by the precise epitaxial growth processes used to form the bottom layer rather than relatively imprecise non-selective etch processes.

Etching heterojunction interfaces

A light detector comprising a photodetector disposed within an etalon or microcavity. The light detector is sensitive to light having a wavelength resonant with the etalon. Preferably, the etalon is a solid state microcavity having distributed bragg reflectors. The photodetector may be a photodiode, phototransistor or the like. The etalon has a front reflector with reflectivity R and a back reflector with reflectivity R . The photodetector has a double-pass absorption of A. In the present invention, R , R , and A are selected such that R &equals;R (1&minus;A). The combination of the back reflector and absorbing photodetector is indistinguishable from a single reflector of reflectivity R . Therefore, the light detector behaves like an etalon with matched reflectors. Preferably, R is greater than 0.95 and R is greater than 0.98. The photodetector can have a relatively thin absorption layer, thereby providing high speed capability. Even with a low absorption, the photodetector provides high quantum efficiency since it is within the etalon. Preferably, the front reflector is movable such that an etalon cavity length is adjustable. This provides for adjustment of the wavelength at which the light detector is sensitive.

Wavelength tunable narrow linewidth resonant cavity light detectors

Growing community of inventors

San Francisco, CA, United States of America

Fred Sugihwo