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Photoresists are fundamental materials in photolithography and are crucial for precise patterning in microelectronic devices, MEMS, and nanostructures. This paper provides an in-depth review of recent advancements in positive photoresist research and development, focusing on discussion regarding the underlying mechanisms governing their behavior, exploring innovative fabrication techniques, and highlighting the advantages of the photoresist classes discussed. The paper begins by discussing the need for the development of new photoresist technologies, highlighting issues associated with adopting extreme ultraviolet photolithography and addressing these challenges through the development of advanced positive-tone resist materials with improved patterning features, resolution, and sensitivity. Subsequently, it discusses the working mechanisms and synthesis methods of different types and subtypes of photoresists, starting from non-chemically amplified, organic, and inorganic-organic hybrid photoresists and progressing to dry film resists, with an emphasis on the upsides of each. The paper concludes by discussing how future research in the field of lithography-prioritizing concerns related to environmental impacts, improved photoresist material and properties, and utilization of advanced quantum technology-can assist with revolutionizing lithography techniques.

Objective: To describe the management and functional outcome of anorectal malformations and associated anomalies according to Krickenbeck classification., Study Design: Case series., Place and Duration of Study: The Aga Khan University Hospital, Karachi, from January 2002 to December 2012., Methodology: Anorectal anomalies were classified according to Krickenbeck classification. Data was collected and proforma used regarding the primary disease associated anomalies, its management and functional outcome, according to Krickenbeck classification. Cases included were: all those children with imperforate anus managed during the study period. Qualitative variables like gender and functional outcome were reported as frequencies and percentages. Quantitative variables like age were reported as medians with interquartile ranges., Results: There were 84 children in study group. Most common associated anomaly was cardiac (38%), followed by urological anomaly (33%). All children were treated by Posterior Sagittal Anorectoplasty (PSARP). Fistula was present in 64 out of 84 (76%) cases. The most common fistula was rectourethral (33%), followed by recto vestibular (31%). According to Krickenbeck classification, continence was achieved in 62% children; however 27% children were constipated, followed by 12% children having fecal soiling., Conclusion: Functional outcome of anorectal malformation depends upon severity of disease. A thorough evaluation of all infants with ARM should be done with particular focus on cardiovascular (38%) and genitourinary abnormalities (33%).