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According to the ITRS [1] photo mask is a significant challenge for the 22nm technology node requirements and beyond. Mask making capability and cost escalation continue to be critical for future lithography progress. On the technological side mask specifications and complexity have increased more quickly than the half-pitch requirements on the wafer designated by the roadmap due to advanced optical proximity correction and double patterning demands. From the economical perspective mask costs have significantly increased each generation, in which mask writing represents a major portion. The availability of a multi-electron-beam lithography system for mask write application is considered a potential solution to overcome these challenges [2,3].In this paper an update of the development status of a full-package high-throughput multi electron-beam writer, called Multi Shaped Beam (MSB), will be presented. Lithography performance results, which are most relevant for mask writing applications, will be disclosed. The MSB technology is an evolutionary development of the matured single Variable Shaped Beam (VSB) technology. An arrangement of Multi Deflection Arrays (MDA) allows operation with multiple shaped beams of variable size, which can be deflected and controlled individually [4]. This evolutionary MSB approach is associated with a lower level of risk and a relatively short time to implementation compared to the known revolutionary concepts [3,5,6].Lithography performance is demonstrated through exposed pattern. Further details of the substrate positioning platform performance will be disclosed. It will become apparent that the MSB operational mode enables lithography on the same and higher performance level compared to single VSB and that there are no specific additional lithography challenges existing beside those which have already been addressed [1].

This article addresses six typical communication traps regarding COVID-19 which can also be observed with respect to other risk topics. First, we argue that risk communication can slide into what is known as 'risk kitsch'. This refers to the misconception that avoiding risk automatically results in safety. However, the avoidance of one risk always leads to other risks. Life without risk is not possible. We go on to scrutinize the unquestioning belief in numbers. It would seem that describing risks in terms of numbers promises to overcome chaos, provide order, and create a sense of agency over the threatening health risks. However, is this really so? Don't numbers also lie, lead astray, or misrepresent? The third issue we examine is the impact of pictures and individual cases on risk perception. What key pictureor rather what particular graphicshapes the risk perception of COVID-19? What message does it convey? Does it bias and mislead us? The fourth issue involves the use of COVID-19 modeling studies which aim to provide answers to a number of essential questions: How bad can it get? What does it depend on? What can be done? Yet it is clear that not all assumptions underlying modeling computations are valid. Information content is not necessarily the same as reality content. The fifth section examines the question of how politics can navigate through the crisis. Is it navigating with a faulty compass? How defective is the compass? We then consider the question of morality, which is a crucial issue during a pandemic with its life-and-death stakes. Are moral evaluations always helpful? Or does a rigorously moral discourse hinder the necessary consideration of alternative options in dealing with the pandemic? Finally, we will draw some conclusions. What could better risk communication on COVID-19 look like? What can be improved, and how? ARTICLE HISTORY

In the ITRS roadmap [1] increasingly long mask write and cycle time is explicitly addressed as a difficult challenge in mask fabrication for the 16nm technology node and beyond. Write time reduction demands have to be seen in relation to corresponding performance parameters like Line Width Roughness (LWR), resolution, placement as well as CD Uniformity.The previously presented Multi Shaped Beam (MSB) approach [2, 3] is considered a potential solution for high throughput mask write application. In order to fully adapt the MSB concept to future industry's requirements specific optimizations are planned.The key element for achieving write time reduction is a higher probe current at the target, which can be obtained by increasing the number of beamlets as well as applying a higher current density. In the present paper the approach of a 256 beamlet MSB design will be discussed. For a given image field size along with a beamlet number increase both beamlet pitch and size have to be optimized. Out of previous investigations, one finding was that by changing the demagnification after the beam forming section of the MSB column the overall performance can be optimized. Based on first electron-optical simulations for a new final lens a larger demagnification turned out to be advantageous. Stochastic beam blur simulation results for the MSB reduction optics will be presented. During the exposure of a pattern layout the number of used beams, their shape and their distribution within the image field varies, which can lead to space charge distortion effects. In regard to this MSB simulation results obtained for an image field of approximately 10x10µm² will be presented. For the 256 beamlet MSB design and resist sensitivities of 20µC/cm², 40µC/cm² and 100µC/cm² write time and LWR simulations have been performed. For MSB pattern data fracturing an optimized algorithm has been used, which increased the beamlet utilization factor (indicates the mean number of beamlets which are used per multi-shot). Finally an update with regard to the required changes of the data path architecture for the 256 beamlet MSB approach will be given. Data integrity as an important aspect of the production worthiness of such a systems will be discussed specifically.

The development of next-generation lithography (NGL) such as EUV, NIL and maskless lithography (ML2) are driven by the half pitch reduction and increasing integration density of integrated circuits down to the 22nm node and beyond. For electron beam direct write (EBDW) several revolutionary pixel based concepts have been under development since several years. By contrast an evolutionary and full package high throughput multi electron-beam approach called Multi Shaped Beam (MSB), which is based on proven Variable Shaped Beam (VSB) technology, will be presented in this paper.In the recent decade VSB has already been applied in EBDW for device learning, early prototyping and low volume fabrication in production environments for both silicon and compound semiconductor applications. Above all the high resolution and the high flexibility due to the avoidance of expensive masks for critical layers made it an attractive solution for advanced technology nodes down to 32nm half pitch.The limitation in throughput of VSB has been mitigated in a major extension of VSB by the qualification of the cell projection (CP) technology concurrently used with VSB. With CP more pixels in complex shapes can be projected in one shot, enabling a remarkable shot count reduction for repetitive pattern.The most advanced step to extend the mature VSB technology for higher throughput is its parallelization in one column applying MEMS based multi deflection arrays. With this Vistec MSB technology, multiple shaped beamlets are generated simultaneously, each controllable individually in shape size and beam on time. Compared to pixel based ML2 approaches the MSB technology enables the maskless, variable and parallel projection of a large number of pixels per beamlet times the number of beamlets.Basic concepts, exposure examples and performance results of each of the described throughput enhancement steps will be presented.