Dirk Zeidler

High-resolution, high-throughput imaging with a multibeam scanning electron microscope.

Electron–electron interactions and detector bandwidth limit the maximal imaging speed of single‐beam scanning electron microscopes. We use multiple electron beams in a single column and detect secondary electrons in parallel to increase the imaging speed by close to two orders of magnitude and demonstrate imaging for a variety of samples ranging from biological brain tissue to semiconductor wafers.

Further advancing the throughput of a multi-beam SEM

Multiple electron beam SEMs enable detecting structures of few nanometer in diameter at much higher throughputs than possible with single beam electron microscopes at comparable electron probe parameters. Although recent multiple beam SEM development has already demonstrated a large speed increase1, higher throughputs are still required to match the needs of many semiconductor applications2. We demonstrate the next step in the development of multi-beam SEMs by increasing the number of beams and the current per beam. The modularity of the multi-beam concept ensures that design changes in the multi-beam SEM are minimized.

High throughput data acquisition with a multi-beam SEM

Conventional scanning electron microscopes are limited in their ultimate data acquisition rate at a given resolution by statistical electron-electron interaction (so-called Coulomb interaction) as well as band width of detectors and deflection systems. We increased imaging speed dramatically by using multiple electron beams in a single column and parallel detection of the secondary electrons. The multi-beam SEM generates multiple overlapping images during a single scan pass, thereby covering a larger area in shorter time as compared to a single-beam SEM at the same pixel size. This addresses the upcoming need for high speed imaging at electron microscopic resolution to investigate larger and larger areas and volumes.

Organ-to-Cell-Scale Health Assessment Using Geographical Information System Approaches with Multibeam Scanning Electron Microscopy

This study combines novel multibeam electron microscopy with a geographical information system approach to create a first, seamless, navigable anatomic map of the human hip and its cellular inhabitants. Using spatial information acquired by localizing relevant map landmarks (e.g. cells, blood vessels), network modeling will enable disease epidemiology studies in populations of cells inhabiting tissues and organs.

Massively parallel E-beam inspection: enabling next-generation patterned defect inspection for wafer and mask manufacturing

SEMATECH aims to identify and enable disruptive technologies to meet the ever-increasing demands of semiconductor high volume manufacturing (HVM). As such, a program was initiated in 2012 focused on high-speed e-beam defect inspection as a complement, and eventual successor, to bright field optical patterned defect inspection [1]. The primary goal is to enable a new technology to overcome the key gaps that are limiting modern day inspection in the fab; primarily, throughput and sensitivity to detect ultra-small critical defects. The program specifically targets revolutionary solutions based on massively parallel e-beam technologies, as opposed to incremental improvements to existing e-beam and optical inspection platforms. Wafer inspection is the primary target, but attention is also being paid to next generation mask inspection. During the first phase of the multi-year program multiple technologies were reviewed, a down-selection was made to the top candidates, and evaluations began on proof of concept systems. A champion technology has been selected and as of late 2014 the program has begun to move into the core technology maturation phase in order to enable eventual commercialization of an HVM system. Performance data from early proof of concept systems will be shown along with roadmaps to achieving HVM performance. SEMATECH’s vision for moving from early-stage development to commercialization will be shown, including plans for development with industry leading technology providers.

Enabling future generation high-speed inspection through a massively parallel e-beam approach

New device architectures and materials are being introduced to develop 10 and 7 nm node manufacturing processes. In addition, the increasing complexity of multiple patterning adds significant yield challenges. The critical metrology challenges for yield assurance include defect control, control of critical dimension and critical dimension uniformity, and pattern placement control. To support the industry in meeting those challenges SEMATECH continues to evaluate new disruptive metrology technologies that can meet the requirements for high volume manufacturing (HVM). High-speed massively parallel e-beam defect inspection has the potential to address the key gaps limiting todays patterned defect inspection in the fab; primarily, throughput and sensitivity to detect ultra-small critical defects. While SEMATECH targets patterned defect inspection first, the technology also has the potential to support the increasing number of hot spot inspection requirements related to critical dimension uniformity and pattern placement that come with self-aligned quadruple patterning. In addition to wafer applications, next generation mask inspection will benefit from a faster high resolution inspection technology. In late 2014 SEMATECH completed a review, system analysis, and proof of concept evaluation of multiple e-beam technologies for patterned wafer inspection. The selection of a champion technology was made and a core technology maturation phase started with the goal of enabling the eventual commercialization of an HVM system. This paper begins with a brief overview of the industry need and the program being developed to address it. Key technical topics pertaining to imaging performance and defect sensitivity are then examined. Performance data from early proof of concept systems will be shown. The capabilities in development to accurately access defect sensitivity using the core technology will be discussed, and initial results for two types of samples will be provided. Development towards the next generation of non-proprietary test samples will also be presented.

Creating High-Resolution Multiscale Maps of Human Tissue Using Multi-beam SEM

Multi-beam scanning electron microscopy (mSEM) enables high-throughput, nano-resolution imaging of macroscopic tissue samples, providing an unprecedented means for structure-function characterization of biological tissues and their cellular inhabitants, seamlessly across multiple length scales. Here we describe computational methods to reconstruct and navigate a multitude of high-resolution mSEM images of the human hip. We calculated cross-correlation shift vectors between overlapping images and used a mass-spring-damper model for optimal global registration. We utilized the Google Maps API to create an interactive map and provide open access to our reconstructed mSEM datasets to both the public and scientific communities via our website www.mechbio.org. The nano- to macro-scale map reveals the tissue’s biological and material constituents. Living inhabitants of the hip bone (e.g. osteocytes) are visible in their local extracellular matrix milieu (comprising collagen and mineral) and embedded in bone’s structural tissue architecture, i.e. the osteonal structures in which layers of mineralized tissue are organized in lamellae around a central blood vessel. Multi-beam SEM and our presented methodology enable an unprecedented, comprehensive understanding of health and disease from the molecular to organ length scale.

Multi-beam SEM technology for ultra-high throughput

E-beam based technologies are widely used for metrology applications in both wafer fabs and mask shops due to their intrinsic high resolution capabilities. However, the throughput requirements for defect inspection are orders of magnitude higher than what is traditionally achievable with electron beam technologies. We have developed a novel multi-electron beam based technology to address the existing need for high speed imaging of nanoscale patterns. This technique enables ultra-high image acquisition rates which scale with the number of electron beams. In this article the technology development status and imaging results will be shown, including first results with the multi-beam SEM on EUV masks.

High-throughput multi-beam SEM: quantitative analysis of imaging capabilities at IMEC-N10 logic node

We use the ZEISS MultiSEM to inspect patterns on separated chips of a semiconductor wafer suited for process window characterization at imec-N10 logic node. We systematically analyze the impact of imaging parameters of the MultiSEM on quantitative metrics extracted from the images, e.g., CD repeatability and relative defect capture, and demonstrate that the MultiSEM is able to image the wafer patterns, track their variations through the process conditions of the lithography scanner, and consistently find patterning defects limiting the lithographic process window.

High Throughput Shale Rock Imaging Using Multi-Beam Scanning Electron Microscopy

Even though there has been decade-long ongoing progress in the advancement of scanning electron microscopes (SEMs), the data acquisition rates and therefore the realistically addressable region of interest has been more or less unaltered since. Using multiple electron beams in parallel can overcome the inherent throughput limitations of conventional single-beam electron microscopy. The setup of such a multi-beam SEM has been described elsewhere [1]. Figure 1 visualizes the basic principle of operation.