We present fiber optic technology for 850 nm, VCSEL-based embedded optical computing solutions. We introduce concepts for compact, rugged fiber optic transceivers that provide multi-channel operation at 12.5 Gbps per channel. The transceiver can be placed in close proximity to high performance ASICs to provide direct optical I/O between components. The transceiver is packaged with material having match coefficients of thermal expansion (CTE), and expanded beam optical interface – these features offer survivability and operation over wide temperature ranges.
Avionics has experienced an ever increasing demand for processing power and communication bandwidth. Currently
deployed avionics systems require gigabit communication using opto-electronic transceivers connected with parallel
optical fiber. Ultra Communications has developed a series of transceiver solutions combining ASIC technology with
flip-chip bonding and advanced opto-mechanical molded optics. Ultra Communications custom high speed ASIC chips
are developed using an SoS (silicon on sapphire) process. These circuits are flip chip bonded with sources (VCSEL
arrays) and detectors (PIN diodes) to create an Opto-Electronic Integrated Circuit (OEIC). These have been combined
with micro-optics assemblies to create transceivers with interfaces to standard fiber array (MT) cabling technology. We
present an overview of the demands for transceivers in military applications and how new generation transceivers
leverage both previous generation military optical transceivers as well as commercial high performance computing
We present Single Event Upset (SEU) testing of a parallel fiber optic transceiver designed for communicating data
using commercial Fibre Channel and GbE protocols at data rates up to 2.5 Gbps per channel (on eight parallel
channels). This transceiver was developed for aircraft applications, such as the Joint Strike Fighter (JSF), Raptor and
F/A-18 aircraft, that deploy fiber optic networks using multi-mode fiber operating at 850 nm wavelength. However,
this transceiver may also have applications in space environments. This paper describes the underlying
transceiver component technology, which utilizes complementary metal-oxide semiconductor (CMOS) silicon-onsapphire
circuitry and GaAs VCSEL and PIN devices. We also present results of SEU testing of this transceiver
using heavy ions at Brookhaven National Labs.
Proc. SPIE. 5346, MOEMS and Miniaturized Systems IV
KEYWORDS: Switches, Waveguides, Microopto electromechanical systems, Vertical cavity surface emitting lasers, Chemical elements, Analog electronics, Digital electronics, Signal detection, Systems modeling, Device simulation
Densely integrated systems in the future will incorporate device and communication technologies that span the domains of digital and analog electronics, optics, micro-mechanics, and micro-fluidics. Given the fundamental differences in substrate materials, feature scale and processing requirements between integrated devices in these domains, it is likely that multi-chip, system-in-package, integration solutions will be required for the foreseeable future. The multi-domain nature of these systems necessitates design tools that span multiple energy domains, time and length scales, as well as abstraction levels. This paper describes a case study of the modeling of a photonic/multi-technology system based on a 3D volumetric packaging technology implemented with Fiber Image Guide (FIG) based technology. It is 64x64 fiber crossbar switch implementation using three Silicon-on-Sapphire mixed signal switch die with flip-chip bonded VCSEL and detector arrays. We show a single end-to-end system simulation of the O/E crossbar working across the domains of free-space and guided wave optical propagation, GaAs O/E and E/O devices, analog drivers and receivers and integrated digital control.
We report on optical components for parallel transmit and receive module, operating at 850nm, designed for short haul optical multimode fiber networks. The component is realized by flip-chip bonding of arrayed optoelectronic devices, i.e., VCSEL and PIN detector array, onto ultra-thin silicon- on-sapphire (UTSi) substrate, which is optically transparent and electrically insulated. Flip-chipped assemblies provide several advantages over conventional wire bond techniques, such as extremely low interconnection parasitics that enable high data rates at low power. Using UTSi technology further improves performance by minimizing crosstalk through its insulating substrate while providing the means for a reliable, low cost optical assembly directly onto the substrate. In addition, applying UTSi technology to optical modules allows a higher degree of functional integration within the module. The insulating substrate provides excellent isolation between mixed signal circuitry, enabling the integration of high performance transmitters, receivers and other sensitive analog circuits with digital circuitry on the same substrate. Furthermore, the integration of VCSEL and photodetector array with UTSi circuits for parallel optical interconnects yields several packaging advantages, such as parallelism, scalability, compactness and simplicity.
Ultra-thin silicon-on-sapphire (UTSi) CMOS technology is a commercial, high yield silicon-on-sapphire technology that yields circuitry well suited for optical communication functions on a transparent substrate. This characteristic, unique to the silicon-on-sapphire configuration, allows flip-chip bonding of optoelectronic (OE) devices onto CMOS circuitry to build Flipped Optoelectronic Chip on UTSi (FOCUTS) optical transmit and receive modules. Flip-chip bonding eliminates the wire-bond inductance between driving/receiving circuits and the OE devices which becomes problematic at data rates greater than about 2.5 Gbps. Such flip-chip integration also reduces the number of discrete components that must be handled, packaged, and aligned in a module, thereby improving reliability and reducing costs. Additional functions, such as Electrically Erasable Programmable Read Only Memory (EEPROM) and self aligned Automatic Power Control (APC) photodetectors and control circuits will be discussed. We describe measured results of flip-chip bonding of arrayed OE devices (VCSELs and photodetectors) and test results at 3 Gbps as well as recent integrating and testing of phototransistors in UTSi circuits. We also describe the radiation sensitivity of all components and applicability of this technique to remote sensing applications. These devices, operating at 850 nm, are aimed at multimode, short reach optical fiber networks.