Exposure assessment and health surveillance in compound semiconductor production

1.通过工作环境和个人暴露采样进行暴露评估：在一家砷化镓晶片制造厂，测量了区域和个人样本中的砷和镓浓度。工艺包括液封直拉法(LEC)、钢锭切片、晶片研磨、晶片抛光和金属有机气相外延。大多数工艺中的砷/镓浓度极低。然而，LEC清洁工人的元素砷暴露水平相对较高。钢锭切片作业人员可接触高浓度的砷化镓。通过生物监测进行暴露评估：通过测定尿液和头发中砷的化学形态，对砷化镓晶片制造商的砷暴露进行生物监测。提示钢锭切片作业工人尿无机砷浓度升高。健康监测：对作业工人进行血液学、生化、免疫学检查和尿卟啉代谢物测定，以评估作业人员的健康状况。没有与暴露相关的变化。结论：LEC清洗和钢锭切片过程对元素砷和砷化镓的暴露水平较高。然而，如果使用适当的控制技术，工人的健康状况是可以保持良好的。

1. Exposure assessment by working environment and personal exposure sampling : In a gallium arsenide wafers manufacturing plant, arsenic and gallium concentrations of area and personal samples were measured. Processes were Liquid Encapsulated Czochralski (LEC), ingot slicing, wafer lapping, wafer polishing, and Metal Organic Vapor Phase Epitaxy. Arsenic/gallium concentrations in most processes were extremely low. However, exposure levels to elemental arsenic of the LEC cleaning workers were relatively high. The ingot slicing workers could be exposed to high concentrations of gallium arsenide.2. Exposure assessment by biological monitoring : Biological monitoring of arsenic exposure in gallium arsenide wafer manufacturers was performed by chemical species determination of arsenic in urine and hair. It was suggested that urinary inorganic arsenic concentrations of the ingot slicing workers elevated.3. Health surveillance : Hematological, biochemical and immunological tests and determination of urinary porphyrin metabolites (coproporphyrins) were performed to assess the health status of the workers. There were no exposure-related change.4. Conclusion : The LEC cleaning and the ingot slicing processes were relatively high exposure levels to elemental arsenic and gallium arsenide. However, the health status of the workers could keep good if the proper control technology was used.