Advantest Develops Semiconductor Circuit Analysis Terahertz Technology

Poised to Accelerate Sub-Terahertz Communications, Chip & 3D Device R&D

http://www.marketwatch.com/story/advantest-develops-semiconductor-circuit-analysis-terahertz-technology-2015-05-21?reflink=MW_news_stmp

TOKYO, May 21, 2015 (BUSINESS WIRE) -- Leading semiconductor test equipment supplier Advantest Corporation ATE, +0.00% announced today that it has developed a technology utilizing short-pulse terahertz waves for analysis of electrical circuits. The technology has 2 major applications – analysis of the transmission characteristics (S parameters) of devices using the sub-terahertz band (100GHz~1THz), and characterization and location of failures in chip circuits (TDT/TDR). The new technology overcomes the technical obstacles and prohibitive cost of existing technologies, and will contribute significantly to the development and wider adoption of these leading-edge devices.

1. Sub-terahertz transmission characteristics analysis technology

The popularity of smartphones and other mobile devices has driven enormous increases in wireless communications traffic, which now threatens to overwhelm the capacity of currently assigned frequencies. Hence, worldwide R&D efforts have begun to focus on the sub-terahertz band, a higher frequency range which has not been used for wireless communications to date.

In high-frequency device development, it is crucial to evaluate the frequency characteristics of the overall system, including active device gain and input and output impedance, as well as the board and connectors. Part of this process is measurement of the reflection and transmission characteristics of the amplitude and phase of signals emitted, known as S-parameters or scattering parameters. However, existing network analyzers can only measure frequency ranges up to 100GHz wide at one time, so when the signal characteristics of broader ranges must be evaluated, engineers have to repeatedly change the configuration of their equipment and measure again. This causes extra work, longer measurement times, and discontinuities in measured data. Measurement costs also rise proportionately to these drawbacks.

Advantest’s new technology promises to reduce these burdens significantly. It employs femtosecond optical pulsed laser as a signal source, enabling one-pass measurement of S-parameters up to 1.5THz with a broadband optical/electrical switching probe. The benefits of these efficiency gains will accrue to users in terms of time, labor, and cost savings.

2. High spatial resolution chip wiring quality analysis technology

Although continued shrinks of semiconductor circuits have facilitated generations of smaller, faster consumer electronics, Moore’s law is in danger of hitting a technological wall. To circumvent the physical limits of miniaturization, chipmakers are developing 3D semiconductors with multiple layers of circuits in a single package. However, wiring failure analysis is a major challenge in 3D chip development. With multiple boards stacked on top of each other, it is difficult to identify where wiring failures (open circuits, short-circuits, impedance mismatching) have occurred with X-ray inspection and other existing technologies. Generally, oscilloscope TDR (time domain reflectometry) and/or TDT (time domain transmissometry) is used to pinpoint these failures, but at these tiny geometries, extremely high spatial resolution is a must.

Because Advantest’s new technology uses a femtosecond optical pulsed laser as a signal source, it achieves superior spatial resolution of less than 5m and a maximum measurement range of 300mm. With a successful track record of usage in the company’s terahertz spectroscopic and imaging systems, Advantest’s femtosecond optical pulsed laser boasts extremely high resolution. Moreover, the new technology provides a mapping function which can pinpoint the location of wiring failures on the device’s CAD data, making it an optimal tool for finding flaws in extremely complex, high-density circuits.

Advantest is planning to commercialize the new technology within its fiscal year 2015 (by the end of March, 2016). A prototype system utilizing the new technology will be exhibited at Wireless Technology Park, to be held at Tokyo’s Big Sight on May 27-29, 2015.

About Advantest Corporation

A world-class technology company, Advantest is the leading producer of automatic test equipment (ATE) for the semiconductor industry and a premier manufacturer of measuring instruments used in the design and production of electronic instruments and systems. Its leading-edge systems and products are integrated into the most advanced semiconductor production lines in the world. The company also focuses on R&D for emerging markets that benefit from advancements in nanotech and terahertz technologies, and has introduced multi-vision metrology scanning electron microscopes essential to photomask manufacturing, as well as a groundbreaking 3D imaging and analysis tools. Founded in Tokyo in 1954, Advantest established its first subsidiary in 1982, in the USA, and now has subsidiaries worldwide. More information is available atwww.advantest.com.

View source version on businesswire.com:http://www.businesswire.com/news/home/20150521005754/en/

SOURCE: Advantest Corporation

Advantest Corporation 
Hiroki Yanagita, 088-3-3214-7500 
Hiroki.Yanagita@advantest.com

Abstract-Sub-cycle control of terahertz high-harmonic generation by dynamical Bloch oscillations

• O. Schubert,
• M. Hohenleutner,
• F. Langer,
• B. Urbanek,
• C. Lange,
• U. Huttner,
• D. Golde,
• T. Meier,
• M. Kira,
• S. W. Koch
• & R. Huber
• • http://www.nature.com/nphoton/journal/vaop/ncurrent/full/nphoton.2013.349.html

Ultrafast charge transport in strongly biased semiconductors is at the heart of high-speed electronics, electro-optics and fundamental solid-state physics^{1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13}. Intense light pulses in the terahertz spectral range have opened fascinating vistas^{14, 15, 16, 17, 18,19, 20, 21}. Because terahertz photon energies are far below typical electronic interband resonances, a stable electromagnetic waveform may serve as a precisely adjustable bias^{5, 11, 17, 19}. Novel quantum phenomena have been anticipated for terahertz amplitudes, reaching atomic field strengths^8, 9, 10. We exploit controlled (multi-)terahertz waveforms with peak fields of 72 MV cm⁻¹ to drive coherent interband polarization combined with dynamical Bloch oscillations in semiconducting gallium selenide. These dynamics entail the emission of phase-stable high-harmonic transients, covering the entire terahertz-to-visible spectral domain between 0.1 and 675 THz. Quantum interference of different ionization paths of accelerated charge carriers is controlled via the waveform of the driving field and explained by a quantum theory of inter- and intraband dynamics. Our results pave the way towards all-coherent terahertz-rate electronic

Euramet schedules Fall meeting

http://www.euramet.org/index.php?id=emrp_events#c11946

2013 MRS Fall Meeting & Exhibit, 1-6 December 2013, Boston, USA

The 2013 MRS (Materials Research Society) Fall Meeting and Exhibit will provide a unique opportunity to bring together participants from all sectors of the global materials and engineering communities.

The following EMRP projects will be presented at the meeting:

• Traceable characterisation of nanostructured devices (NEW01 TReND) will support the semiconductor industry by developing and improving the methods for characterising the chemical and electrical properties of nanostructures, and make comparisons between the different techniques.
• Metrology for the manufacturing of thin films (IND07 Thin Films) will improve the nanoscale measurements needed to develop thin film technologies, improving our understanding of film properties and reducing material and energy costs.

Another new use for Terahertz-thanks numbrcruntchr

Terahertz Waves Are Effective Probes for IC Heat Barriers

Credit: Shutterstock

By modifying a commonly used commercial infrared spectrometer to allow operation at long-wave terahertz frequencies, researchers at the National Institute of Standards and Technology (NIST) discovered an efficient new approach to measure key structural properties of nanoscale metal-oxide films used in high-speed integrated circuits. Their technique, described in a recent paper,* could become an important quality-control tool to help monitor semiconductor manufacturing processes and evaluate new insulating materials.

Chip manufacturers deposit complicated mazes of layered metallic conductor and semiconconductor films interlaced with insulating metal oxide nanofilms to form transistors and conduct heat. Because high electrical leakage and excess heat can cause nanoscale devices to operate inefficiently or fail, manufacturers need to know the dielectric and mechanical properties of these nanofilms to predict how well they will perform in smaller, faster devices.

Manufacturers typically assay the structure of metal oxide films using X-ray spectroscopy and atomic force microscopy, both tedious and time-consuming processes. NIST researchers discovered that they could extract comparable levels of detail about the structural characteristics of these thin films by measuring their absorption of terahertz radiation, which falls between the infrared and microwave spectral regions.

Although terahertz spectroscopy is known to be very sensitive to crystal and molecular structure, the degree to which the metal oxide films absorbed the terahertz light was a surprise to NIST researchers.

“No one thought nanometer-thick films could be detected at all using terahertz spectroscopy, and I expected that the radiation would pass right through them,” says Ted Heilweil, a NIST chemist and co-author of the paper. “Contrary to these expectations, the signals we observed were huge.”

The NIST team found that the atoms in the films they tested move in concert and absorb specific frequencies of terahertz radiation corresponding to those motions. From these absorbed frequencies the team was able to extrapolate detailed information about the crystalline and amorphous composition of the metal oxide films, replete with structures that could affect their function.

The team’s experiments showed that a 40 nanometer thick hafnium oxide film grown at 581 kelvin (307 degrees Celsius) had an amorphous structure with crystalline regions spread throughout; nanofilms grown at lower temperatures, however, were consistently amorphous. According to Heilweil, an approximately 5 nanometer film thickness is the detection limit of the terahertz method, and the efficacy of the technique depends to some degree on the type of metal oxide, though the group noted that all metal-oxide materials surveyed exhibit distinct spectral characteristics.

* E. Heilweil, J. Maslar, W. Kimes, N. Bassim and P. Schenck. Characterization of metal-oxide nanofilm morphologies and composition by terahertz transmission spectroscopy. Optics Letters. 34 (9), 1360–1362 (2009).

Media Contact: Mark Esser, mark.esser@nist.gov, (301) 975-8735