Satomi Shioiri

Fast optical proximity correction: analytical method

In automating optical proximity correction, calculation speed becomes important. In this paper we present a novel method for calculating proximity corrected features analytically. The calculation will take only several times the amount it takes to calculate intensity of one point on wafer. Therefore, the calculation will become extremely faster than conventional repetitive aerial image calculations. This method is applied to a simple periodic pattern. The simulated results show great improvement on linearity after correction and have proved the effectiveness of this analytical method.

112Gb/s optical transponder with PM-QPSK and coherent detection employing parallel FPGA-based real-time digital signal processing, FEC and 100GbE Ethernet interface

We demonstrate 112Gb/s transmission using PM-QPSK format and FPGA-based real-time digital signal processing. By employing framed processing architecture for polarization demultiplexing and carrier phase estimation, stable operation of error free after FEC and wide frequency offset have been achieved.

A 10 Gb/s SiGe bipolar framer/demultiplexer for SDH systems

A 10 Gb/s 1:8 frame detecting demultiplexer requires 50% less accuracy of frame detection timing control. This 10 Gb/s demultiplexer with frame detection is fabricated using a SiGe Bipolar process. The relaxation of the accuracy requirement is achieved by a data shift selection architecture. This IC is constructed by a combination of a data shift selection circuit and a parallel shift register circuit. In this architecture, the most accurate control is required in a counter operating at 5 GHz. The core circuit of the IC dissipates only 1.8 W with -4.5 V supply voltage.

Precise analysis of transmission impairments of Pol-Mux 110Gb/s RZ-DQPSK with automatic Pol-Dmux using straight 2,000-km SMF line

Transmission of Pol-Mux 110 Gb/s RZ-DQPSK signal with automatic Pol-Dmux at receiver over straight 2,000-km SMF line with +3 dBm/ch shows that the performance is mainly governed by OSNR and PMD.

A 2.5-Gb/s high-speed PLC module for Gigabit-To-The-Home (GTTH) system

A PLC module with an avalanche photodiode (APD) and a one-chip receiver IC was developed for use in an ultrabroadband optical access system. The module provides 2.5-Gbit/s downlink capacity and is the fastest PLC module ever reported to our knowledge.

Comparison of 100Gb/s transmission performances between RZ-DQPSK and polarization multiplexed NRZ/RZ-DPSK with automatic polarization de-multiplexer

Long-term transmission performances of polarization multiplexed 2x50 Gb/s NRZ/RZ-DPSK signals, denoting good transmission performances but with larger PMD-induced BER fluctuations compared with 100 Gb/s RZ-DQPSK, are successfully observed by constructing an automatic polarization de-multiplexer.

Optical proximity correction of alternating phase-shift masks for 0.18-um KrF lithography

Optical proximity correction (OPC) was applied to alternating phase shift masks to improve printed resist pattern fidelity. Mask patterns were modified with jog type corrections. DRAM cell patterns were exposed by using a 0.55 NA, 0.36/0.55 (sigma) , KrF excimer laser stepper onto 0.5 micrometers thick chemically amplified negative resist. With 0.55 (sigma) , OPC was effective and printed resist pattern was very close to designed one. However, with 0.36 (sigma) , large pattern deformation was observed due to coma aberration.

Standing Wave Effect of Various Illumination Methods in 0.25 μm KrF Excimer Laser Lithography

Illumination dependence of the standing wave effect was investigated by experiment and simulation in variously sized line and space (LS however, in the defocused region of ±0.6 µ m, necessary for actual device fabrication, the amplitudes of these illuminations were smaller than that of low σ illumination. Moreover, it was found that the amplitude variation was closely related to the log-slope value of exposure light intensity distribution at the nominal pattern edge.

A method of accurately optimizing the timing of phase modulation in wide temporal ranges for DQPSK transmitters

We propose and verify experimentally a method of accurately setting the timing of phase modulation over temporal ranges wider than 1 symbol period for DQPSK transmitters, allowing Q to be optimized within 0.1 dB.

A 1 Gb/s 8-channel array OEIC with SiGe photodetectors

A 1 Gb/s 8-channel array opto-electronic integrated circuit (OEIC) fabricated with SiGe photodetectors receives a 0.98 /spl mu/m photo signal. Monolithic integration of SiGe photodetectors and dc coupling between preamplifier and limiter, without an external capacitor, enables fabrication of small and low-cost optical receiver modules. For dc coupling, an offset cancel circuit with a mirror integrator produces a low-pass filter having a large time constant without an external capacitor and compensates the offset voltage. The receiver circuit operates with 3.3 V supply for low power dissipation and is surrounded by a trench for reduced crosstalk. A SiGe photodetector has 20% external quantum efficiency at 0.980 /spl mu/m. The receiver sensitivity is -10.4 dB.