Diamond photodetectors for next generation 157-nm deep-UV photolithography tools

Abstract Next generation photolithography stepper tools will operate at 157 nm and require robust solid state photodetectors to ensure efficient operation and facilitate direct beam monitoring for photoresist exposure dosimetry. There is currently no commercial detector system able to fully meet all the demanding requirements of this application. Diamond, which is intrinsically visible blind and radiation hard, is an obvious candidate for consideration. In this paper we report the results of the first study to assess the viability of thin film polycrystalline diamond photodetectors for use in 157 nm F2-He based laser lithography tools. Co-planar inter-digitated gold photoconductor structures were fabricated on free standing thin film diamond and exposed to pulses from an industrial F2-He laser in the fluence range 0-1.4 mJ cm-2. The electrical and optical characteristics of the devices have been measured and are compared to the response of a standard vacuum photodiode. The suitability of the diamond devices for use at 157 nm is discussed

Injuries at a Canadian National Taekwondo Championships: a prospective study

BACKGROUND: The purpose of this prospective study was to assess the injury rates in male and female adult Canadian Taekwondo athletes relative to total number of injuries, type and body part injured. METHODS: Subjects (219 males, 99 females) participated in the 1997 Canadian National Taekwondo Championships in Toronto, Canada. Injuries were recorded on an injury form to documents any injury seen and treatment provided by the health care team. These data were later used for this study. The injury form describes the athlete and nature, site, severity and mechanism of the injury. RESULTS: The overall rate of injuries was 62.9/1,000 athlete-exposures (A-E). The males (79.9/1,000 A-E) sustained significantly more injuries than the females (25.3/1,000 A-E). The lower extremities were the most commonly injured body region in the men (32.0 /1,000 A-E), followed by the head and neck (18.3/1,000 A-E). Injuries to the spine (neck, upper back, low back and coccyx) were the third most often injured body region in males (13.8/1,000 A-E). All injuries to the women were sustained to the lower extremities. The most common type of injury in women was the contusion (15.2/1,000 A-E). However, men's most common type of injury was the sprain (22.8/1,000 A-E) followed by joint dysfunction (13.7/1,000A-E). Concussions were only reported in males (6.9/1,000 A-E). Compared to international counterparts, the Canadian men and women recorded lower total injury rates. However, the males incurred more cerebral concussions than their American colleagues (4.7/1,000 A-E). CONCLUSIONS: Similar to what was found in previous studies, the current investigation seems to suggest that areas of particular concern for preventive measures involve the head and neck as well as the lower extremities. This is the first paper to identify spinal joint dysfunction

Consensus statement on abusive head trauma in infants and young children

Abusive head trauma (AHT) is the leading cause of fatal head injuries in children younger than 2 years. A multidisciplinary team bases this diagnosis on history, physical examination, imaging and laboratory findings. Because the etiology of the injury is multifactorial (shaking, shaking and impact, impact, etc.) the current best and inclusive term is AHT. There is no controversy concerning the medical validity of the existence of AHT, with multiple components including subdural hematoma, intracranial and spinal changes, complex retinal hemorrhages, and rib and other fractures that are inconsistent with the provided mechanism of trauma. The workup must exclude medical diseases that can mimic AHT. However, the courtroom has become a forum for speculative theories that cannot be reconciled with generally accepted medical literature. There is no reliable medical evidence that the following processes are causative in the constellation of injuries of AHT: cerebral sinovenous thrombosis, hypoxic-ischemic injury, lumbar puncture or dysphagic choking/vomiting. There is no substantiation, at a time remote from birth, that an asymptomatic birth-related subdural hemorrhage can result in rebleeding and sudden collapse. Further, a diagnosis of AHT is a medical conclusion, not a legal determination of the intent of the perpetrator or a diagnosis of murder. We hope that this consensus document reduces confusion by recommending to judges and jurors the tools necessary to distinguish genuine evidence-based opinions of the relevant medical community from legal arguments or etiological speculations that are unwarranted by the clinical findings, medical evidence and evidence-based literature

Diamond-based 1-D imaging arrays

Diamond has shown great promise for the fabrication of high sensitivity, low dark current, fast and visible-blind deep UV photodetectors. In addition to careful choice of substrate material, defect passivation treatments applied to the diamond after growth have been found to considerably enhance the detector characteristics achieved. In this paper we report on the first purposefully designed 1-D CVD diamond imaging array for the detection of nanosecond 193 nm excimer laser pulses using this approach. It is shown to perform extremely well, giving less than 2% pixel-to-pixel variation in signal response, and is fast enough to avoid any sign of charge build up during prolonged operation