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This experiment is concerned with control of organic contaminants accumulated on the silicon surface during wafer storage and handling. A rapid optical surface treatment ͑ROST͒ employing white light illumination from a halogen lamp in ambient air is used for this purpose. The results obtained indicate that the effectiveness of removal of surface organic contaminants using this treatment depends on the type of organic contaminants accumulated on the surface which in turn depends on the storage time and ambient in which the wafer is stored. The ROST was found to be as effective as other methods of organic contamination removal, including wet treatments, when the Si surface needs to be ''refreshed'' through organic volatilization following shipment or short-term storage. However, it is not as effective as standard wet cleans in the case of wafers stored for a prolonged period of time and frequently exposed to ambient air of varied composition. In particular, this treatment applied prior to gate oxidation is demonstrated to have a beneficial effect on the reliability of thin gate oxides. It is postulated that ROST may play a useful role in the processing of incoming wafers.Surface contaminants encountered in microelectronics manufacturing can be considered in terms of those added to the surface during processing and those added during wafer storage. The first group concerns contaminants originating from the process gases, chemicals, and equipment and includes organic and metallic contaminants as well as particles and moisture. The second group concerns contaminants from the storage and shipping environment including cleanroom air, containers, boxes, and cassettes. Assuming storage is accomplished in a particle-free environment, the contaminants originating from storage include primarily organic contaminants 1 and moisture. 2 Hence, these two can be considered to be key contributors to the surface aging process, which may interfere with subsequent processes, 3 or measurements such as ellipsometric measurements, or noncontact measurements of electrical characteristics of the surface. 4 At present, the most common solution to the problem of surface deposits accumulated during wafer shipment and storage is a surface cleaning procedure using a sequence of wet cleaning steps. This time and resources consuming routine should be replaced with simpler and less involved methods of surface refreshing. None among the alternative approaches, however, offers efficiency and simplicity at the same time. The use of ozonated deionized ͑DI͒ water rinse 5,6 requires dedicated wet processing equipment and wafer drying capability while a UV/O 2 exposure 7,8 requires enclosed reactors with an ozone annihilation facility. Even as simple a process as a hot plate anneal in ambient air has a drawback of having the back surface of the wafer in contact with a heating plate which may cause contamination of the wafer.In earlier work we have introduced the concept and studied feasibility of lamp cleaning using a rapid optical surface treatment ͑ROS...

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This study is concerned with variations of the concentration of active boron dopant in the near surface region of silicon wafers. Boron can be deactivated by pairing with hydrogen or metals, particularly Cu and Fe, all of which may originate from the surface polishing process. The temperature dependence of boron activation is studied using the surface charge profiling method. Based on the determined activation energy of 1.28 eV it was concluded that in the p-type wafers used in this study initially observed boron deactivation was dominated by its interaction with hydrogen introduced during wafer polishing.