Selective and lithography-independent fabrication of 20 nm nano-gap electrodes and nano-channels for nanoelectrofluidics applications

A new method has been developed to selectively fabricate nano-gap electrodes and nano-channels by conventional lithography. Based on a sacrificial spacer process, we have successfully obtained sub-100-nm nano-gap electrodes and nano-channels and further reduced the dimensions to 20 nm by shrinking the sacrificial spacer size. Our method shows good selectivity between nano-gap electrodes and nano-channels due to different sacrificial spacer etch conditions. There is no length limit for the nano-gap electrode and the nano-channel. The method reported in this paper also allows for wafer scale fabrication, high throughput, low cost, and good compatibility with modern semiconductor technology.

A Selective-Area Metal Bonding InGaAsP-Si Laser

A 1.55-mu m hybrid InGaAsP-Si laser was fabricated by the selective-area metal bonding method. Two Si blocking stripes, each with an excess-metals accommodated space, were used to separate the optical coupling area and the metal bonding areas. In such a structure, the air gap between the InGaAsP structure and Si waveguide has been reduced to be negligible. The laser operates with a threshold current density of 1.7 kA/cm(2) and a slope efficiency of 0.05 W/A under pulsed-wave operation. Room-temperature continuous lasing with a maximum output power of 0.45 mW is realized.

Harmonic Millimeter Wave Generation and Frequency Up-Conversion Using Optical Injection Locking and Brillouin Selective Sideband Amplification

Harmonic millimeter wave (mm-wave) generation and frequency up-conversion are experimentally demonstrated using optical injection locking and Brillouin selective sideband amplification (BSSA) induced by stimulated Brillouin scattering in a 10-km single-mode fiber. By using this method, we successfully generate third-harmonic mm-wave at 27 GHz (f(LO) - 9 GHz) with single sideband (SSB) modulation and up-convert the 2GHz intermediate frequency signal into the mm-wave band with single mode modulation of the SSB modes. In addition, the mm-wave carrier obtains more than 23 dB power gain due to the BSSA. The transmission experiments show that the generated mm-wave and up-converted signals indicate strong immunity against the chromatic dispersion of the fibers.

A 10-GHz Bandwidth Electroabsorption Modulated Laser by Ultra-Low-Pressure Selective Area Growth

A novel integration technique has been developed using band-gap energy control of InGaAsP/InGaAsP multiquantum-well (MQW) structures during simultaneous ultra-low-pressure (22 mbar) selective-area-growth (SAG) process in metal-organic chemical vapour deposition. A fundamental study of the controllability of band gap energy by the SAG method is performed. A large band-gap photoluminescence wavelength shift of 83nm is obtained with a small mask width variation (0-30μm). The method is then applied to fabricate an MQW distributed-feedback laser monolithically integrated with an electroabsorption modulator. The experimental results exhibit superior device characteristics with low threshold of 19mA, over 24 dB extinction ratio when coupled into a single mode fibre. More than 10 GHz modulation bandwidth is also achieved, which demonstrates that the ultra-low-pressure SAG technique is a promising approach for high-speed transmission photonic integrated circuits.

Selective Area Growth InGaAsP by MOVPE

The wide stripe (ISjum) selective area growth (SAG) of InGaAsP by low pressure MOVPE is systematically investigated. The characteristics of the growth ratios,thickness enhancement factors .bandgap modulation,and composition modulation vary with the growth conditions such as mask width,growth pressure. Flux of III-group precursors are outlined and the rational mechanism behind SAG MOVPE is explained. In addition,the surface spike of the SAG InGaAsP is shown and the course of it is given by the variation of V /III .

Wavelength Tuning in Two-Section Distributed Bragg Reflector Laser by Selective Intermixing of InGaAp-InGaAsP Quantum Well Structure

The two-section tunable ridge waveguide distributed Bragg reflector (DBR) laser fabricated by the selective intermixing of an InGaAsP-InGaAsP quantum well structure is presented. The threshold current of the laser is 51mA. The tunable range of the laser is 4.6nm, and the side mode suppression ratio (SMSR) is 40dB.

1.5μm Self-Aligned Spotsize Converter Integrated DFB Fabricated by Selective Area Grown MOVPE

High performance 1.57μm spotsize converter monolithically integrated DFB is fabricated by the technique of self-aligned selective area growth. The upper optical confinement layer and the butt-coupled tapered thickness waveguide are regrown simultaneously, which not only offeres the separated optimization of the active region and the integrated spotsize converter, but also reduces the difficulty of the butt-joint selective regrowth. The threshold current is as low as 4.4mA. The output power at 49mA is 10.1mW. The side mode suppression ratio (SMSR) is 33.2dB. The vertical and horizontal far field divergence angles are as small as 9° and 15° respectively, the 1dB misalignment tolerance are 3.6μm and 3.4μm.

Spotsize Converter Integrated DFB Laser Diode Using Selective Area Growth of MOCVD

The characteristics of thickness enhancement factor and bandgap wavelength of selectively grown In-GaAsP are investigated. A high thickness enhancement factor of 2.9 is obtained. Spotsize converter integrated DFB lasers are fabricated by using the technique of SAG. The threshold current is as low as 10.8mA. The output power is 10m W at 60mA without coating and the SMSR is 35.8dB. The vertical far field angle (FWHM) is decreased from 34 °to 9 °. The tolerance of 1dBm misalignment is 3.4μm vertically.

Monolithic Integration of DFB Laser Diode and Electroabsorption Modulator by Selective Area Growth Technology

国家863计划

Multi-Wavelength InGaAsP Lasers Grown by LP-MOCVD Selective Area Growth

国家863计划

A new wavelength selective photoreceiver

于2010-11-23批量导入

Selective intermixing of Ga(In)NAs/GaAs quantum well structures usingSiO(2) encapsulation and rapid thermal annealing

The quantum well intermixing of Ga(In)NAs/GaAs simple quantum well (SQW) using SiO2 encapsulation and rapid thermal annealing has been studied. Obvious enhanced intermixing of GaInNAs/GaAs SQW was observed due to the localized SiO2 capping layer and RTA at temperature between 650degreesC and 900degreesC. The selective intermixing strongly depends on N composition and In composition. An obvious selective intermixing had been found in the samples with small N composition and/or high In composition.