Polymer Bound Photobase Generators And Photoacid Generators For Pitch Division Lithography

The semiconductor industry is pursuing several process options that provide pathways to printing images smaller than the theoretical resolution limit of 193 nm projection scanners. These processes include double patterning, side wall deposition and pitch division. Pitch doubling lithography (PDL), the achievement of pitch division by addition of a photobase generator (PBG) to typical 193 nm resist formulations was recently presented. 1 Controlling the net acid concentration as a function of dose by incorporating both a photoacid generator (PAG) and a PBG in the resist formulation imparts a resist dissolution rate response modulation at twice the frequency of the aerial image. Simulation and patterning of 45 nm half pitch L/S patterns produced using a 90 nm half pitch mask were reported. 2 Pitch division was achieved, but the line edge roughness of the resulting images did not meet the current standard. To reduce line edge roughness, polymer bound PBGs and polymer bound PAGs were investigated in the PDL resist formulations. The synthesis, purification, analysis, and functional performance of various polymers containing PBG or PAG monomers are described herein. Both polymer bound PBG with monomeric PAG and polymer bound PAG with monomeric PBG showed a PDL response. The performance of the polymer bound formulations is compared to the same formulations with small molecule analogs of PAG and PBG.Chemical Engineerin

Women Filmmakers in the United Arab Emirates

This entry provides an introduction to the work of and the challenges faced by women filmmakers in the United Arab Emirates while at the same time providing an overview of the emerging film industry in the country. The fact that these women claim the power of representation and start telling their stories against the backdrop of a conservative, patriarchal society, obviously opens up space for gender redefinition. Overall, it seems that their films reveal a preference for strong, interesting women that fight for a meaningful life against the backdrop of a globalized society that has left women weaker and more fragile, with less obvious choices and possibilities for fulfillment. As their female characters claim center stage, both traditional and contemporary constructions of gender are called into question and popular stereotypes about Emirati women are challenged

Photobase Generator Enabled Pitch Division: A Progress Report

Pitch division lithography (PDL) with a photobase generator (PBG) allows printing of grating images with twice the pitch of a mask. The proof-of-concept has been published in the previous paper[1, 2] and demonstrated by others[1]. Forty five nm half-pitch (HP) patterns were produced using a 90nm HP mask, but the image had line edge roughness (LER) that does not meet requirements. Efforts have been made to understand and improve the LER in this process. Challenges were summarized toward low LER and good performing pitch division. Simulations and analysis showed the necessity for an optical image that is uniform in the z direction in order for pitch division to be successful. Two-stage PBGs were designed for enhancement of resist chemical contrast. New pitch division resists with polymer-bound PAGs and PBGs, and various PBGs were tested. This paper focuses on analysis of the LER problems and efforts to improve patterning performance in pitch division lithography.Chemical Engineerin

Antitumor activity from antigen-specific CD8 T cells generated in vivo from genetically engineered human hematopoietic stem cells

The goal of cancer immunotherapy is the generation of an effective, stable, and self-renewing antitumor T-cell population. One such approach involves the use of high-affinity cancer-specific T-cell receptors in gene-therapy protocols. Here, we present the generation of functional tumor-specific human T cells in vivo from genetically modified human hematopoietic stem cells (hHSC) using a human/mouse chimera model. Transduced hHSC expressing an HLA-A*0201–restricted melanoma-specific T-cell receptor were introduced into humanized mice, resulting in the generation of a sizeable melanoma-specific naïve CD8^+ T-cell population. Following tumor challenge, these transgenic CD8^+ T cells, in the absence of additional manipulation, limited and cleared human melanoma tumors in vivo. Furthermore, the genetically enhanced T cells underwent proper thymic selection, because we did not observe any responses against non–HLA-matched tumors, and no killing of any kind occurred in the absence of a human thymus. Finally, the transduced hHSC established long-term bone marrow engraftment. These studies present a potential therapeutic approach and an important tool to understand better and to optimize the human immune response to melanoma and, potentially, to other types of cancer

Interspecies and Interregional Analysis of the Comparative Histologic Thickness and Laser Doppler Blood Flow Measurements at Five Cutaneous Sites in Nine Species

Studies in dermatology, cutaneous pharmacology, and toxicology utilize skin from different animal species and body sites. However, regional differences exist in topical chemical percutaneous absorption studies in man and in animals. The objective of this study was to compare epidermal thickness and number of cell layers across species and body sites using both formalin-fixed paraffin and frozen sections. Cutaneous blood flow determined by laser Doppler velocimetry (LDV)was compared to histologic data. Six animals of each of the following species were used: monkeys, pigs, dogs, cats, cows, horses, rabbits, rats, and mice. Cutaneous blood flow was determined and 6-mm skin biopsies were taken directly from the following sites: buttocks, ear, humeroscapular joint, thoracolumbar junction, and abdominal area. When the two histologic methods were compared across all species and body sites, the thickness of the epidermis was significantly greater, and the thickness of the stratum corneum significantly less, in paraffin sections versus frozen sections (p < 0.05). There were no differences in the number of viable cell layers determined by both methods. The values for LDV-determined blood flow did not significantly correlate (p > 0.05) to epidermal or stratum corneum thickness. However, regional and species differences were noted in all these parameters. In conclusion, these data indicate that thickness and LDV blood flow are independent and must be evaluated separately when comparisons are made between species and body sites. This work provides a data base for future comparative studies in which a knowledge of skin thickness or blood flow might be important variables

The play is a prison : the discourse of Prison Shakespeare.

The relationship between Shakespeare and prison was brought into sharp focus during Shakespeare’s recent quad-centenary with a succession of works exploring Shakespeare’s value for the prison population. In this paper, we take this spike in activity as a point of departure for examining the discourse of Prison Shakespeare. This discourse, we argue, is underpinned by several intertwining and sometimes paradoxical accounts of social being: (i) psychoanalytic accounts; (ii) postmodern accounts; (iii) humanist accounts bound up with the idea of cultural unfolding; (iv) neoliberal accounts that champion heroic individualism. In our analysis, we respond to Pensalfini’s call for critical debate over the assumption that Shakespeare's plays have the power to both teach and liberate prisoners. We note how Prison Shakespeare is always in a struggle to escape the institutional power of both Shakespearean drama and the prison context itself, and the tendency of this work to provide a model of socialization into, rather than resistance against, what Bristol describes as the mode of subjectivity of the bourgeois political economy

Neurology

Contains reports on eight research projects.United States Air Force (AF33(616)-7588, AF49(638)-1130)National Science Foundation (Grant G-16526)United States Army Chemical Corps (DA-18-108-405-Cml-942)United States Public Health Service (B-3055, B-3090)United States Navy, Office of Naval Research (Contract Nonr-1841(70)