Hermes Microvision Inc.

Asml Netherlands B.v.

Schlumberger Technologies, Inc.

Applied Materials, Inc.

Kla-tencor Technologies Corporation

Nptest, Inc.

Kenichi Kanai

Weiming Ren

Zhongwei Chen

Xuedong Liu

Juying Dou

Yongxin Wang

Stoyan Nihtianov

Zhonghua Dong

Chiwoei Wayne Lo

Yi-Xiang Wang

Xinqing Liang

Gianpaolo Lorito

Indranil De

Kurt H Weiner

Zhong-wei Chen

Yan Zhao

Yi Xiang Wang

Jay Jianhui Chen

Zheng Fan

Rui-Ling Lai

Jun Jiang

Hui Wang

Suresh N Rajan

Qingyu Meng

Hiroyasu Koike

Wei-Ming Ren

Xue-Dong Liu

The present disclosure describes a detector used in critical dimension scanning electron microscopes (CD-SEM) and review SEM systems. In one embodiment, the detector includes a semiconductor structure having a p-n junction and a hole through which a scanning beam is passed to a target. The detector also includes a top electrode for the p-n junction (e.g., anode or cathode) that provides an active area for detecting electrons or electromagnetic radiation (e.g., backscattering from the target). The top electrode has a doped layer and can also have a buried portion beneath the doped layer to reduce a series resistance of the top electrode without changing the active area. In another embodiment, an isolation structure can be formed in the semiconductor structure near sidewalls of the hole to electrically isolate the active area from the sidewalls. A method for forming the buried portion of the top electrode is also described.

Semiconductor detector and method of fabricating same

A detector may be provided with an array of sensing elements. The detector may include a semiconductor substrate including the array, and a circuit configured to count a number of charged particles incident on the detector. The circuit of the detector may be configured to process outputs from the plurality of sensing elements and increment a counter in response to a charged particle arrival event on a sensing element of the array. Various counting modes may be used. Counting may be based on energy ranges. Numbers of charged particles may be counted at a certain energy range and an overflow flag may be set when overflow is encountered in a sensing element. The circuit may be configured to determine a time stamp of respective charged particle arrival events occurring at each sensing element. Size of the sensing element may be determined based on criteria for enabling charged particle counting.

Semiconductor charged particle detector for microscopy

A wafer grounding apparatus and method adaptable to a charged particle beam apparatus is disclosed. A wafer substrate is supported by a wafer mount. A pulse current pin is arranged to be in contact with a backside film formed on a backside of the wafer substrate. A grounding pulse generator provides at least one pulse to drive the pulse current pin such that dielectric breakdown occurring at the backside film leads to establishment of a current path through the backside films. Accordingly, a current flows in the wafer substrate through this current path and then flows out of the wafer substrate via at least one current return path formed from capacitive coupling between the wafer substrate and the wafer mount.

Wafer grounding and biasing method, apparatus, and application

A wafer grounding apparatus and method adaptable to a charged particle beam apparatus is disclosed. A wafer substrate is supported by a wafer mount. A grounding pin is arranged to be in contact with a backside film formed on a backside of the wafer substrate. A grounding pulse generator provides at least one pulse to drive the grounding pin such that dielectric breakdown occurring at the backside film leads to establishment of a current path through the backside films. Accordingly, a current flows in the wafer substrate through this current path and then flows out of the wafer substrate via at least one current return path formed from capacitive coupling between the wafer substrate and the wafer mount.

An apparatus basically uses a simple and compact multi-axis magnetic lens to focus each of a plurality of charged particle beams on sample surface at the same time. In each sub-lens module of the multi-axis magnetic lens, two magnetic rings are respectively inserted into upper and lower holes with non-magnetic radial gap. Each gap size is small enough to keep a sufficient magnetic coupling and large enough to get a sufficient axial symmetry of magnetic scale potential distribution in the space near to its optical axis. This method eliminates the non-axisymmetric transverse field in each sub-lens and the round lens field difference among all sub-lenses at the same time; both exist inherently in a conventional multi-axis magnetic lens. In the apparatus, some additional magnetic shielding measures such as magnetic shielding tubes, plates and house are used to eliminate the non-axisymmetric transverse field on the charged particle path from each charged particle source to the entrance of each sub-lens and from the exit of each sub-lens to the sample surface.

Apparatus of plural charged particle beams with multi-axis magnetic lens

An apparatus for increasing electric conductivity to a wafer substrate, when exposed to electron beam irradiation, is disclosed. More specifically, a methodology to breakdown the insulating layer on wafer backside is provided to significantly reduce the damage on the wafer backside while proceeding with the grounding process.

Wafer grounding methodology

The present invention relates to a multi-axis magnetic lens for a charged particle beam system. The apparatus eliminates the undesired non-axisymmetric transverse magnetic field components from the magnetic field generated by a common excitation coil and leaves the desired axisymmetric field for focusing each particle beam employed within the system.

Multi-axis magnetic lens

A method of raster scanning a sample on a continuously moving stage for charged-particle beam imaging said sample is disclosed. The method includes line scanning a charged-particle beam across a surface of the sample repeatedly to form on the surface at least one 2-dimensional line array composed of scan lines lying adjacent to each other. When each line scan is to be performed, the charged-particle beam is shifted, along the stage-moving direction, by an extra predefined distance at least equal to a distance the stage has traveled during a time period from the beginning of the first line scan of the first formed line array to the beginning of the current line scan (to be performed) of the current line array (to be formed).

Method and apparatus for obtaining images by raster scanning charged particle beam over patterned substrate on a continuous mode stage

One embodiment relates to an electron beam apparatus. The apparatus includes a mechanism for moving a substrate relative to the electron beam column at a controlled speed. A probe beam gun is configured to generate a probe beam through the column, and a pre-charging beam gun configured to generate a pre-charging beam through the column. Control circuitry configured to pre-scan a scan line with the pre-charging beam at least once and to subsequently sense scan the scan line with the probe beam at least once. The control circuitry is further configured so that there is a prescribed delay time between said pre-scanning and said sense scanning of the scan line. In another embodiment, a single electron beam and a deflection system configured to deflect the electron beam into pre-scans and sense scans. Other embodiments and features are also disclosed.

Electrical defect detection using pre-charge and sense scanning with prescribed delays

Methods and apparatus, including computer program products, implementing and using techniques for open-loop waveform acquisition. In general, in one aspect, the invention provides a method for open-loop waveform acquisition. The method includes acquiring an S-curve of an acquisition loop of an electron-beam probe system. The S-curve represents a response of the acquisition loop to changes of potential differences between the acquisition loop and a device under test. The method includes calibrating the acquisition loop to obtain a linear region in the acquired S-curve and using the linear portion of the acquired S-curve to calculate voltage at a probe point of the device under test.

Open-loop for waveform acquisition

Defects in a patterned substrate are detected by inspection with a charged particle beam inspection tool which generates an image of a portion of the patterned substrate and compares the image with a reference in order to identify any defects in the patterned substrate. Parameters of the tool are optimized to improve image uniformity and contrast, particularly voltage contrast. Prior to imaging an area of the substrate, the tool charges an area surrounding the image area to eliminate or reduce the effects caused by asymmetrical charging in the surrounding area. The tool alternates between charging the surrounding area and imaging the image area to produce a plurality of images of the image area, which are then averaged. The result is a highly uniform image with improved contrast for accurate defect detection.

Voltage contrast method and apparatus for semiconductor inspection using low voltage particle beam

Voltage contrast method for semiconductor inspection using low voltage particle beam

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Palo Alto, CA, United States of America

Kenichi Kanai