Fracture of alumino-borosilicate glass-aluminum joints

A no. of aluminoborosilicate glass-aluminum bonds were prepd. by thermocompression, resulting in fracture toughness values of 0.5-0.9 MPa.m1/2. Relatively high temp. and pressure have a pos. influence, while prolonged pressure time is unfavorable, due to the formation of a very thin reaction layer. Fracture energies, cor. for the amt. of nonbonded area, vary from 2-6 J/m2. An est. of the contributions to the measured fracture energy gives a difference of a factor 3-4 with the exptl. value. There is room, however, for considerable improvement in processing and modeling. [on SciFinder (R)

Polarization converter post-processing for integrated polarization independent SOA

Post-processing of a polarization converter (PC) in an experimental industrial generic foundry process is demonstrated. Insertion of the PC halfway an SOA reduced its polarization dependence from 14 dB to 3 dB

The performance of organic electronic ratchets

Organic electronic ratchets rectify time-correlated external driving forces, giving output powers that can drive electronic circuitry. In this work their performance characteristics are investigated using numerical modeling and measurements. It is shown how the characteristic parameters of the time–varying asymmetric potential like length scales and amplitude, as well as the density and mobility of the charge carriers in the device influence the performance characteristics. Various ratchet efficiencies and their relations are discussed. With all settings close to optimum, a ratchet with charge displacement and power efficiencies close to 50% and 7% respectively is obtained

Fullerene-assisted electron-beam lithography for pattern improvement and loss reduction in InP membrane waveguide devices

In this Letter, we present a method to prepare a mixed electron-beam resist composed of a positive resist (ZEP520A) and C 60 fullerene. The addition of C 60 to the ZEP resist changes the material properties under electron beam exposure significantly. An improvement in the thermal resistance of the mixed material has been demonstrated by fabricating multimode interference couplers and coupling regions of microring resonators. The fabrication of distributed Bragg reflector structures has shown improvement in terms of pattern definition accuracy with respect to the same structures fabricated with normal ZEP resist. Straight InP membrane waveguides with different lengths have been fabricated using this mixed resist. A decrease of the propagation loss from 6.6 to 3.3¿¿dB/cm has been demonstrated

The 243 steps of making photonic integrated circuits in InP

The fabrication ofInP-based Photonic Integrated Circuits (PICs) is a complex process. The process used in the COBRA cleanroom in Eindhoven consists of 13 deposition, 10 lithography, 14 dry- and 7 wet-etching steps. Together with the intermediate cleaning, preparation and inspection procedures, the total process flow consists of 243 steps. In this paper we show how we created a robust modular process flow that can be usedfor a large variety of active- and passive circuits. These circuits can be fabricated together in multi-project wafer runs, allowing a drastic reduction of the fabrication costs making even small-volume production economicallyfeasible

The 243 steps of making photonic integrated circuits in InP

The fabrication ofInP-based Photonic Integrated Circuits (PICs) is a complex process. The process used in the COBRA cleanroom in Eindhoven consists of 13 deposition, 10 lithography, 14 dry- and 7 wet-etching steps. Together with the intermediate cleaning, preparation and inspection procedures, the total process flow consists of 243 steps. In this paper we show how we created a robust modular process flow that can be usedfor a large variety of active- and passive circuits. These circuits can be fabricated together in multi-project wafer runs, allowing a drastic reduction of the fabrication costs making even small-volume production economicallyfeasible

III-V-on-silicon multi-frequency lasers

Compact multi-frequency lasers are realized by combining III-V based optical amplifiers with silicon waveguide optical demultiplexers using a heterogeneous integration process based on adhesive wafer bonding. Both devices using arrayed waveguide grating routers as well as devices using ring resonators as the demultiplexer showed lasing with threshold currents between 30 and 40 mA and output powers in the order of a few mW. Laser operation up to 60°C is demonstrated. The small bending radius allowable for the silicon waveguides results in a short cavity length, ensuring stable lasing in a single longitudinal mode, even with relaxed values for the intra-cavity filter bandwidths