Dual-Lens Electron Holography for Junction Profiling and Strain Mapping of Semiconductor Devices (original) (raw)

Strain Mapping on Semiconductor Device by Dark Field Electron Holography

Microscopy and Microanalysis, 2010

Dark field electron holography with dual lens operation to achieve high spatial resolution is summarized. Its application to measure strain on semiconductor devices is reported and comparison with converging beam electron diffraction (CBED) and nano-beam electron diffraction (NBD) is discussed. o 2070 Route 52,

Quantitative electron holography of biased semiconductor devices

2002

Electron holography is used to measure electrostatic potential profiles across reverse-biased Si pn junctions in situ in the transmission electron microscope. A novel sample geometry based on focused ion-beam milling is developed, and results are obtained for a range of sample thicknesses and bias voltages to allow the holographic contrast to be interpreted. The physical and electrical nature of the sample surface, which is affected by sample preparation and electron beam irradiation, is discussed.

Strain mapping in layers and devices by electron holography

physica status solidi (a), 2010

Phone: þ33 (0) 5 62 25 78 00, Fax: þ33 Strain can be measured at the micron scale by Raman spectroscopy and X-ray diffraction, but at the nanoscale, the only viable tool is transmission electron microscopy (TEM). TEM techniques can be divided into two categories: diffraction based techniques such as convergent-beam-electron-diffraction or nanobeam electron diffraction, and imaged based techniques such as high-resolution electron microscopy or the new technique of dark-field electron holography (HoloDark). The latter has recently been invented to measure strain to high precision (2 Â 10 À4 ), nanometer spatial resolution, and for micron fields of view. In this article, we present two latest and typical results from the HoloDark technique (which is applicable to all standard focused-ion beam prepared crystalline samples): mapping of strain in contact etch stop layers induced strain structures, and in implanted layers, In such materials and structures, the Holodark technique, although still perfectible, has no competitor.

Electron holography of biased semiconductor devices

2003

ABSTRACT: Off-axis and in-line electron holography have been used to examine a Si pn junction under applied electrical bias. The experiments reveal the internal and external electrostatic potential distribution in the device. A quantitative analysis of the results was carried out using simulations, allowing a best-fitting model for the internal electrostatic potential distribution to be determined.

Dark-field electron holography as a recording of crystal diffraction in real space: a comparative study with high-resolution X-ray diffraction for strain analysis of MOSFETs

Journal of Applied Crystallography, 2020

Diffraction-based techniques, with either electrons or photons, are commonly used in materials science to measure elastic strain in crystalline specimens. In this paper, the focus is on two advanced techniques capable of accessing strain information at the nanoscale: high-resolution X-ray diffraction (HRXRD) and the transmission electron microscopy technique of dark-field electron holography (DFEH). Both experimentally record an image formed by a diffracted beam: a map of the intensity in the vicinity of a Bragg reflection spot in the former, and an interference pattern in the latter. The theory that governs these experiments will be described in a unified framework. The role of the geometric phase, which encodes the displacement field of a set of atomic planes in the resulting diffracted beam, is emphasized. A detailed comparison of experimental results acquired at a synchrotron and with a state-of-the-art transmission electron microscope is presented for the same test structure: a...

Strain mapping in MOSFETS by high-resolution electron microscopy and electron holography

Materials Science and Engineering: B, 2008

We present two methods for mapping strains in MOSFETs at the nanometer scale. Aberration-corrected high-resolution transmission electron microscopy (HRTEM) coupled with geometric phase analysis (GPA) provides sufficient signal-to-noise to accurately determine strain fields across the active regions of devices. Finite element method (FEM) simulations are used to confirm our measurements. The field of view is however limited to about 100 nm 2. To overcome this, we have developed a new technique called dark-field holography based on off-axis electron holography and dark-field imaging. This new technique provides us a better strain resolution than HRTEM, a spatial resolution of 4 nm and a field of view of 1 m.

Towards electron holography of working transistors

2012

As semiconductor device dimensions are reduced to the deep sub-micron regime, minor departures from the designed distributions of electrostatic potentials can affect device performance dramatically. Parameter optimisation in device processing and modelling is crucial for achieving precise potential profiles. Such optimisation is not possible without comprehensive feedback from advanced characterisation techniques. The ability to acquire This thesis could not have been completed without the generous help of many people to whom I am deeply indebted. Firstly, I would like to express my deepest gratitude to my supervisors, Prof. David McComb and Dr. Alison Harrison, for their endless support, encouragement and guidance. I am deeply grateful to Dr. Takeshi Kasama for his assistance with electron microscopy, invaluable discussions and constructive comments on this thesis. I am much indebted to Prof. Rafal Dunin-Borkowski for his invaluable advice, supervision and moreover, using his precious times to read this thesis and give constructive, rigorous and critical comments about it. I would like to thank