National Semiconductor Corporation

Bruce Carlton Roberts

Luu Thanh Nguyen

William Paul Mazotti

Ken Pham

Peter Deane

Jia Liu

John P Briant

Stephen Gee

Neeraj Anil Pendse

Michael R Nelson

Janet E Townsend

Roger William Clarke

Christopher James Smith

Jitendra Mohan

Yongseon Koh

Christopher Barratt

Lionel Auzereau

Hau Thanh Nguyen

Stephen Jacob

A high performance and small-scale circuitry substrate is described. The circuitry substrate includes a dielectric layer, a return plane attached to a bottom surface of the dielectric layer, and a plurality of return paths (ground) and signal lines that are attached to a top surface of the dielectric layer. The return paths on the top surface are connected to the return plane on the bottom surface by wrapping around at least one edge of the dielectric material. Return paths on the top layer can also separate each pair or adjacent signal lines. The circuitry substrate can be advantageously used to form an optoelectronic module.

Two-layer electrical substrate for optical devices

Optoelectronic components, specifically, ceramic optical sub-assemblies are described. In one aspect, the optoelectronic component includes a ceramic base substrate having a pair of angled (or substantially perpendicular) faces. The electrical traces are formed directly on the ceramic surfaces and extend between the pair of faces. A semiconductor chip assembly is mounted on the first face of the ceramic base substrate and a photonic device is mounted on the second face. Both the semiconductor chip assembly and the photonic device are electrically connected to traces on the ceramic base substrate. The semiconductor chip assembly is generally arranged to be electrically connected to external devices. The photonic devices are generally arranged to optically communicate with one or more optical fibers. The described structure may be used with a wide variety of photonic devices. It is particularly well adapted for use with vertical cavity surface emitting lasers (or laser arrays) and detectors (or detector arrays). In some embodiments, at least the cathode of the photonic device is soldered directly to a cathode pad on the base substrate. Similarly, in some embodiments, the semiconductor chip assembly is electrically connected to the base substrate by direct soldering. Specific base substrate structures are disclosed as well.

Ceramic optical sub-assembly for optoelectronic modules

The present invention provides a low cost device that has a true die to external fiber optic connection. Specifically, the present invention relates to an optical device package joined to a semiconductor device package. In some cases, the combination is joined using wirebond studs and an adhesive material. In other cases, the combination is joined using an anisotropic conductive film. Yet, in other cases, the combination is joined using solder material. Each of these joining mechanisms provides high levels of thermal, electrical and optical performance. The joining mechanisms can apply to optical sub-assembly and chip sub-assembly interfaces in transceivers, transmitters, as well as receivers for opto-electronic packages.

Techniques for joining an opto-electronic module to a semiconductor package

This disclosure describes a clear overmolding cap for protecting the photonic devices in optoelectronic packages from damage due to handling, module assembly, board assembly, and environmental exposure in field applications. The overmolding of the devices with a clear mold cap or similar material also provides a standoff for optical fibers positioned next to the active facets. The photonic devices are attached to a substrate, which may be flexible that has electronic traces that allow the photonic devices to be connected to an external device such as a semiconductor device. A technique for manufacturing the overmolding cap using a mold die system in combination with a rigid carrier is also disclosed. The rigid carrier is used to maintain the shape of the substrate during the molding process. The proposed method applies to photonic devices used in optoelectronic packages that can serve as transceivers, transmitters, or receivers.

Technique for protecting photonic devices in optoelectronic packages with clear overmolding

A high performance ceramic block for use with small-scale circuitry is described. The block can be used in an optical sub-assembly (OSA) suitable for optical interconnection with optical fibers and electrical interconnection with a chip sub-assembly (CSA) is formed. The block includes a first surface and a second surface and is formed using one of low temperature co-fired ceramic (LTCC) and high temperature co-fired ceramic (HTCC) techniques. Photonic devices are formed on the first surface of the ceramic block and electrical contacts are formed on a second surface of the block. The electrical contacts being suitable for electrical communication with a chip sub-assembly. Electrical connections are formed so that they pass internally through the ceramic block to electrically interconnect the photonic devices on the first face of the block with the electrical contacts on the second face of the block. Such a block can be advantageously used to form an optoelectronic module.

Ceramic optical sub-assembly for opto-electronic module utilizing LTCC (low-temperature co-fired ceramic) technology

Concepts for conveniently arranging devices for the transduction of signals to and from voltage and current domains to infrared radiation domains is described. Specifically, optoelectronic components and methods of making the same are described. In one aspect, the optoelectronic component includes a base substrate having a pair of angled (or substantially perpendicular) faces with electrical traces extending therebetween. A semiconductor chip assembly is mounted on the first face of the base substrate and a photonic device is mounted on the second face. Both the semiconductor chip assembly and the photonic device are electrically connected to traces on the base substrate. The semiconductor chip assembly is generally arranged to be electrically connected to external devices. The photonic devices are generally arranged to optically communicate with one or more optical fibers. The described structure may be used with a wide variety of photonic devices. In some embodiments the base substrate is formed from a ceramic material having the electrical traces formed thereon. In other implementations the substrate includes a backing block having a flexible printed circuit substrate adhered thereto.

Optical sub-assembly for opto-electronic modules

The techniques of the present invention are directed towards setting a photonic device into a groove of a substrate, which is then attached to the chip sub-assembly in a way that the resulting optoelectronic package has a low profile and the interconnects between the photonic device and the semiconductor chip are short. The technique involves partially etching a groove in a substrate to allow for positioning of a photonic device within the groove. The photonic device is connected to the chip sub-assembly through interconnects that extend through the thickness of the substrate. The photonic devices are placed on their sides so that the active facets are perpendicular to the main axis of the chip sub-assembly. In this configuration, the optical fibers can be positioned parallel to the CSA top surface, ensuring a low module profile in the process.

Techniques for attaching rotated photonic devices to an optical sub-assembly in an optoelectronic package

Optical sub-assembly for optoelectronic modules

The present invention provides a technique for manufacturing a low cost device that provides a true die to external fiber optic connection. Specifically, the present invention relates to several techniques for joining an optical device package to a semiconductor device package. The first technique involves using wirebond studs and an adhesive material, the second technique involves the use of an anisotropic conductive film, and the third technique involves the use of solder material. Each of these techniques provides high levels of thermal, electrical and optical performance. The methods apply to optical sub-assembly and chip sub-assembly interfaces in transceivers, transmitters, as well as receivers for opto-electronic packages.

An embodiment includes a connector element that comprises a connector body and a fiber optic ferrule slidably positioned inside the connector body. The ferrule holds at least one optical fiber. The connector element carries an optical sub-assembly including a photonic device and a spacer and includes a connector sleeve for receiving the connector element. The sleeve includes a ridge that operates as a first stop for the connector body and includes an alignment projection that coarsely aligns the fiber optic ferrule. The ferrule includes a pair of openings configured to receive a pair of alignment pins to provide fine alignment of optical fibers with corresponding photonic devices. The connector element is engaged with the connector sleeve to position the ferrule with respect to the optical sub-assembly such that the optical fiber is correctly positioned relative to a corresponding photonic device. Also, the invention teaches a method of using the described apparatus to position optical fibers relative to corresponding photonic devices of an optical sub-assembly.

Miniature form-factor connecter for fiber optic modules

The invention comprises a connector apparatus for electrically interconnecting a chip sub-assembly to an optical sub-assembly. The apparatus includes a connector sleeve with a chip sub-assembly having at least one electrical connection arranged thereon. The connector sleeve is suitable for receiving a connector plug that includes an optical fiber optically coupled to the photonic devices of an optical sub-assembly that includes electrical connectors. The connector plug is engaged with the connector sleeve, thereby electrically interconnecting the electrical connections of the chip sub-assembly to the electrical connectors of the optical sub-assembly such that electrical signals can pass between the chip sub-assembly and a photonic device of the optical sub-assembly.

Growing community of inventors

San Jose, CA, United States of America

Bruce Carlton Roberts