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BACKGROUND Zanthoxylum bungeanum pericarps (ZBP) are commonly used as food additives and traditional herbal medicines. Several mineral elements are known to have important physiological functions in organisms, whereas others are reported to have toxic effects. We determined levels of macro elements (Mg, S and Ca), essential trace elements (B, Mn, Fe, Cu, Zn, Se and Mo) and toxic elements (Ni, Al, Cr, As, Cd, Hg and Pb) in the pericarps of 19 Z. bungeanum cultivars. Hazard index values and incremental lifetime cancer risks were calculated to express health risks associated with pericarp consumption. Moreover, several chemometric analyses based on the mineral elements were used to distinguish Z. bungeanum cultivars. RESULTS The concentrations of 17 determined elements in the pericarps were ranked: Ca > Mg > S > Fe > Al > Mn > Zn > B > Cu > Ni > Pb > Cr > Mo > As > Cd > Hg > Se. The elements Zn, Cr and As had the highest variations in their concentrations. Cu, Mn, Se, Zn, Al, As, Cd, Cr, Hg, Ni and Pb posed some non-cancer risks, while As and Cd posed cancer risks. Mn, Fe, Zn, and Al were chosen as critical element markers for assessing ZBP using chemometric analyses. CONCLUSION Chemometric analyses could highlight mineral concentration differentiation among the 19 cultivars. The Z. bungeanum cultivar Z12 (from Wudu, Gansu) is best for producing ZBP, and cultivar Z18 (Guanling, Guizhou) can be a reference to classify and evaluate ZBP quality. The results provide valuable information for evaluating the potential safety risks of ZBP and contribute to inter-cultivar discrimination. © 2021 Society of Chemical Industry.

This work presents our investigations on a new resist-slope kernel for Mask Process Correction (MPC) applications, specifically modeling the contribution (including linear and higher-order) of the resist image slope to the overall etch bias. Mask Process Correction (MPC) models with different complexities, i.e., varying number of kernels, were calibrated and compared against each other for model accuracy, layout correction run-time and dose-dependent residual trends. The results demonstrate that using the resist-slope kernel with a simpler model can allow for up to 40 percent lower correction run-time (compared to complex models) without a major degradation of the overall model accuracy. Hence, this paper presents the resist-slope kernel as a valuable addition to MPC modeling techniques, especially for situations where conventional methods are not sufficient to meet the accuracy or run time requirements.

In the advanced technology photomask manufacturing industry, it is challenging to produce defect-free photomasks, especially for the increasingly smaller critical dimension current days . Since the 193nm immersion scanner numerical aperture (1.35) has remained the same as in previous nodes, more mult i-patterning and aggressive source mask optimizat ion illumination sources are being used to print smaller feature crit ical dimensions (CDs) and pitches. To accommodate such specialized sources, more model -based mask OPC and ILT are being used, making mask designs very complicated. This in turn makes mask manufacturing very challenging , especially for the defect inspection, repair, and metrology processes that are used to guarantee defect-free masks. So, it is necessary to develop an application for handling mask defects. In this paper, we introduce a new application called LPR (Lithography Printability Review) to verify any outlier defects or repairs before the mask ships to the wafer fab. The paper details how LPR works in the mask-making flow and how the LPR module is set up. This application has been tightly integrated with KLA’s server and inspectors. The paper concludes with showing the benefits realized in mask making cycle time as a result of implementing LPR into a high volume advanced photomask production line.

According to the data of May, August and October 1992, the range of Hg content in Jiaozhou Bay waters was 0.009-0.050 μg /L, which met the water quality standard of class I sea water. This showed that in terms of Hg content, in May, August and October, the water of Jiaozhou Bay was clean and free from any Hg pollution. In May, the range of Hg content in Jiaozhou Bay waters was 0.009-0.038 μg /L. In August, the range of Hg content in Jiaozhou Bay waters was 0.021-0.050 μg/L. In October, the range of Hg content in Jiaozhou Bay waters was 0.011-0.040 μg /L. There were two sources of Hg content in Jiaozhou Bay waters, surface runoff and atmospheric deposition. The Hg content from surface runoffwas 0.038-0.040 μg /L, and that from atmospheric deposition was 0.050 μg /L. The model diagram was established to show the different paths and contents of Hg content in the process of input into Jiaozhou Bay. In May and October, the surface runoff was not polluted by any Hg content. In August, atmospheric deposition was not contaminated by any Hg content. That revealed that Hg, humans issued to land and atmosphere, finally got to the ocean. There were two paths. One is that human beings discharge Hg into the atmosphere, and the Hg content reached into the ocean through atmospheric sedimentation. The Hg content from atmospheric sedimentation was relatively high, but the transportation time was relatively short. The other is that human beings discharge Hg content to the land. Through surface runoff, the Hg content reached into the ocean, and the Hg content from surface runoff was relatively low, but the transportation time was relatively short. With more and more paths, Hg content was decreasing.

Chinese prickly ash is widely cultivated as a medicinal and edible plant. The pericarps are extensively used because of their unique flavour and various biological compounds, such as volatile oils, flavonoids, polyphenols, and acid amide. Due to higher financial gain, incongruence in the vernacular names, and similarity in morphology among some species or cultivars, adulteration and associated fraudulent practices may occur in trading these substances. The location, soil conditions, and management actions influence the growth of these plants. Thus, authentication and quality difference evaluations of pericarps from different cultivation regions of Chinese prickly ash are required. First, the ITS2 sequence, a DNA barcode with the advantages of universality, small intraspecific variation, high interspecific divergence, and a small fragment length, was applied to authenticate Chinese prickly ash pericarps collected from 72 plantations. Then, the main quality traits (colour, thousand pericarp weight, numb taste intensity, and volatile oil content) of Chinese prickly ash pericarps among different species were compared. Moreover, the influence of environmental factors on these quality traits of Chinese prickly ash was reported. The results identified confounding in pericarp species in the main cultivation regions (more than two species with red colour). The colour, size, volatile oil content, and ITS2 sequence of pericarps were significantly different among species. Fifty-eight polymorphic sites and two indel sites were identified in the alignment that could differentiate these species using ITS2. In addition, colour distinguished Zanthoxylum armatum from all other species, and size distinguished Z. bungeanum from Z. piperitum (since they both were red), but these two traits which authenticate Chinese prickly ash could have errors due to the similarity of the size and colour among the Chinese prickly ash species. The main quality trait differences and these traits influence among different species were significant, especially between Z. armatum and Z. bungeanum. Latitude of the cultivation region was a key influence factor on the main quality traits of both Z. bungeanum and Z. armatum. In addition, soil pH had a positive effect on the main quality traits of Z. bungeanum, and altitude had a positive effect on taste intensity and a negative effect on the b* of pericarps. Overall, the main quality traits of Chinese prickly ash combined with the molecular method provided useful information to authenticate pericarps of Chinese prickly ash.

With continuous shrinking technology nodes, the error tolerances for mask CD (critical dimension) becomes tighter and tighter since mask errors are passed on downstream and might even be amplified at wafer level. Therefore, high accuracy MPC (Mask Process Correction) models are imperative. Besides the mask model, the MPC algorithm for the input layout also has a critical influence on mask quality. This paper studies and compares two methods of MPC correction: a new method, introducing a correction algorithm based on the CD-SEM box is compared to the standard method that measures EPE (edge placement error) only at the center of an edge. Under which condition the EPE measurement method for MPC correction by the CD-SEM box method should be applied is discussed and its influence on the correction accuracy of small CD patterns is demonstrated.

In semiconductor manufacturing, as the design rule has decreased, the ITRS roadmap requires crucial tighter critical dimension (CD) control. CD uniformity is one of the necessary parameters to assure good performance and reliable functionality of any integrated circuit (IC) [1] [2], and towards the advanced technology nodes, it is a challenge to control CD uniformity well. The study of corresponding CD Uniformity by tuning Post-Exposure bake (PEB) and develop process has some significant progress[3], but CD side to side error happening to some line/space pattern are still found in practical application, and the error has approached to over the uniformity tolerance. After details analysis, even though use several developer types, the CD side to side error has not been found significant relationship to the developing. In addition, it is impossible to correct the CD side to side error by electron beam correction as such error does not appear in all Line/Space pattern masks. In this paper the root cause of CD side to side error is analyzed and the PEB module process are optimized as a main factor for improvement of CD side to side error.

Mask pattern measurement becomes one of the main challenges for the quality evaluation of the mask which is applied with complex lithography optical effect correction. Traditional straight edge mask pattern is evaluated with 1-dimension Critical Dimension (CD) method. But for 2-dimension pattern especially the mask full filled with complex shapes OPC pattern, many special approaches are studied attempt to characterize 2D pattern from different points of view [1-5]. A simple CD’s information and the traditional mask performance evaluation parameters, such as CD mean-to-target and CD uniformity, are no longer suitable to such 2D pattern due to lacking of the pattern’s character descriptions. Therefore the CD performances may not represent the actual wafer printing result in many cases. In addition, non-straight pattern edge induces significant CD measure error which makes it difficult to clarify the real mask pattern making quality. This paper investigates a pattern contour based solution for 2D structure performance evaluation. The basic contours of GDS and CD-SEM image are extracted, overlapped and processed and then the edge roughness of SEM contour and the bias between the above two kinds of contour are adopted on 2D individual pattern performance’s statistics. By utilizing this solution, the 2D pattern quality can be described quantitatively as two main aspects, shape and size with the results of edge roughness and bias. Generalize this solution, the 2D pattern’s uniformity, mean size, or other performances, can be evaluated quantitatively in the similar way as well. This solution calculation bases on pattern contour, therefore the measure pattern is not restricted by its shape.