Frequency response of an internal amplifier in a high-speed integrated circuit measured by electro-optic sampling

SiGe is being extensively investigated for use in heterojunction bipolar-transistors (HBT) and high-speed integrated circuits. The material offers adjustable bandgaps, improved carrier mobilities over Si homostructures, and compatibility with Si-based integrated-circuit manufacturing. SiGe HBT performance can be improved by increasing the base-doping or by widening the base link-region by ion implantation. A problem that arises however is that implantation can enhance strain-relaxation of SiGe/Si.Furthermore, once misfit or threading dislocations result, the defects can give rise to recombination-generation in depletion regions of semiconductor devices. It is of relevance therefore to study the damage and anneal behavior of implanted SiGe layers. The present study investigates the microstructural behavior of phosphorus implanted pseudomorphic metastable Si0.88Ge0.12 films on silicon, exposed to various anneals.Metastable pseudomorphic Si0.88Ge0.12 films were grown ~265 nm thick on a silicon wafer by molecular-beam epitaxy. Pieces of this wafer were then implanted at room temperature with 100 keV phosphorus ions to a dose of 1.5×1015 cm-2.

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The Radio Probe™: A New Measurement Tool for High Speed Integrated Circuits

ISTFA 2005: Conference Proceedings from the 31st International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa2005p0224 ◽

2005 ◽

Author(s):

Mark Kimball

Keyword(s):

Integrated Circuits ◽

Integrated Circuit ◽

High Speed ◽

Attenuation Factor ◽

Cost Effective ◽

Frequency Measurement ◽

Single Frequency ◽

Measurement Tool ◽

Probe Design ◽

Differential Measurement

Abstract This article presents a novel tool designed to allow circuit node measurements in a radio frequency (RF) integrated circuit. The discussion covers RF circuit problems; provides details on the Radio Probe design, which achieves an input impedance of 50Kohms and an overall attenuation factor of 0 dB; and describes signal to noise issues in the output signal, along with their improvement techniques. This cost-effective solution incorporates features that make it well suited to the task of differential measurement of circuit nodes within an RF IC. The Radio Probe concept offers a number of advantages compared to active probes. It is a single frequency measurement tool, so it complements, rather than replaces, active probes.

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High-speed electro-optic switch using buried electrode structure in polymer Mach–Zehnder waveguide

Modern Physics Letters B ◽

10.1142/s0217984916500639 ◽

2016 ◽

Vol 30 (06) ◽

pp. 1650063 ◽

Cited By ~ 1

Author(s):

Jingwen Sun ◽

Jian Sun ◽

Yunji Yi ◽

Lucheng Qv ◽

Shiqi Sun ◽

...

Keyword(s):

Insertion Loss ◽

Rise Time ◽

High Speed ◽

Low Cost ◽

Characteristic Parameters ◽

Electrode Structure ◽

Processing Cost ◽

Electro Optic ◽

Disperse Red 1 ◽

Excellent Photostability

A low-cost and high-speed electro-optic (EO) switch using the guest–host EO material Disperse Red 1/Polymethyl Methacrylate (DR1/PMMA) was designed and fabricated. The DR1/PMMA material presented a low processing cost, an excellent photostability and a large EO coefficient of 13.1 pm/V. To improve the performance of the switch, the in-plane buried electrode structure was introduced in the polymer Mach–Zehnder waveguide to improve the poling and modulating efficiency. The characteristic parameters of the waveguide and the electrodes were carefully designed and the fabrication process was strictly controlled. Under 1550 nm, the insertion loss of the device was 12.7 dB. The measured switching rise time and fall time of the switch were 50.00 ns and 54.29 ns, respectively.

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A New Method to Verify the Measurement Speed and Accuracy of Frequency Modulated Interferometers

Applied Sciences ◽

10.3390/app11135787 ◽

2021 ◽

Vol 11 (13) ◽

pp. 5787

Author(s):

Toan-Thang Vu ◽

Thanh-Tung Vu ◽

Van-Doanh Tran ◽

Thanh-Dong Nguyen ◽

Ngoc-Tam Bui

Keyword(s):

Phase Change ◽

High Speed ◽

Measurement Accuracy ◽

Slow Motion ◽

New Method ◽

Virtual Displacement ◽

Electro Optic ◽

Lock In ◽

Speed And Accuracy ◽

Electro Optic Modulator

The measurement speed and measurement accuracy of a displacement measuring interferometer are key parameters. To verify these parameters, a fast and high-accuracy motion is required. However, the displacement induced by a mechanical actuator generates disadvantageous features, such as slow motion, hysteresis, distortion, and vibration. This paper proposes a new method for a nonmechanical high-speed motion using an electro-optic modulator (EOM). The method is based on the principle that all displacement measuring interferometers measure the phase change to calculate the displacement. This means that the EOM can be used to accurately generate phase change rather than a mechanical actuator. The proposed method is then validated by placing the EOM into an arm of a frequency modulation interferometer. By using two lock-in amplifiers, the phase change in an EOM and, hence, the corresponding virtual displacement could be measured by the interferometer. The measurement showed that the system could achieve a displacement at 20 kHz, a speed of 6.08 mm/s, and a displacement noise level < 100 pm//√Hz above 2 kHz. The proposed virtual displacement can be applied to determine both the measurement speed and accuracy of displacement measuring interferometers, such as homodyne interferometers, heterodyne interferometers, and frequency modulated interferometers.

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