Silicon Carbide (SiC) provides excellent characteristics such as superior thermal conductivity, high carrier mobility and extreme chemical stability in comparison with those of Silicon (Si). SiC is already showing significant device performance benefits in power devices, high performance communication, and LED lighting. However, SiC presents many challenges for wafer surface treatment because of its high hardness and remarkable chemical inertness. Today, mechanical polishing techniques on industrial batch CMP tools are the predominant methods for SiC wafer surface treatment, but material removal rate (MRR), surface defects and wafer flatness control are reaching fundamental limits with increasing wafer diameter. Batch processing typically results in a higher amount of surface scratches and defects, higher wafer to wafer variability, and higher wafer breakage rates. A unique single wafer chemical mechanical polishing (CMP) technique on 150mm n-doped, 4° off-axis, single crystal, 4H-SiC wafers was developed to create a virtually defect-free surface. A polishing head has been designed to manipulate polishing pressures at various zones of the wafer. This capability can modulate the removal thickness at each region on the wafer surface, resulting in a highly uniform wafer profile. Additionally, a CMP slurry has been formulated to maximize MRR from 2μm/hr to over 8.5μm/hr. Potassium permanganate has been selected as an oxidant and aluminum oxide particles as the abrasive. The oxidant concentration and abrasive content along with slurry pH level have also been optimized for ideal chemical and mechanical activity. Scratch-free wafer surfaces are observed with atomic force microscopy (AFM) and bright field (BF) and dark field (DF) inspection techniques. Roughness on the Si face is reduced to below 0.08nm. Total length of surface scratches was reduced to 10mm or less. Industrial metrics of wafer flatness, including total thickness variation (TTV) and local thickness variation (LTV) are modulated and improved. A test run completed on 25-wafers shows an overall 31% improvement of TTV post CMP process.

Vladimir Nabokov complained about the number of Dostoevsky's characters “sinning their way to Jesus.” In truth, Christ is an elusive figure not only in Dostoevsky's novels, but in Russian literature as a whole. The rise of the historical critical method of biblical criticism in the nineteenth century and the growth of secularism it stimulated made an earnest affirmation of Jesus in literature highly problematic. The writers at the heart of this book understood that to reimage Christ for their age, they had to make him known through indirect, even negative ways, lest what they say about him be mistaken for cliché, doctrine, or naïve apologetics. The Christology of Fyodor Dostoevsky, Leo Tolstoy, Mikhail Bulgakov, and Boris Pasternak is thus apophatic because they deploy negative formulations (saying what God is not) in their writings about Jesus. Professions of atheism in Dostoevsky and Tolstoy's non-divine Jesus are but separate negative paths toward truer discernment of Christ. This first study in English of the image of Christ in Russian literature highlights the importance of apophaticism as a theological practice and a literary method in understanding the Russian Christ. It also emphasizes the importance of skepticism in Russian literary attitudes toward Jesus on the part of writers whose private crucibles of doubt produced some of the most provocative and enduring images of Christ in world literature. This important study will appeal to scholars and students of Orthodox Christianity and Russian literature, as well as educated general readers interested in religion and nineteenth-century Russian novels.

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