A high-pressure processing system (300, 400, 500, 600) for processing a layer on a substrate (314, 414), the system comprising: a first chamber (202, 302, 402, 502, 602); a pedestal (304, 404, 504, 604, 700) to support the substrate (314, 414), the pedestal (304, 404, 504, 604, 700) being positioned within the first chamber (202, 302, 402, 502, 602); a second chamber (204, 306, 406, 506, 606) at least partially surrounding the first chamber (202, 302, 402, 502, 602); a vacuum processing system configured to lower a pressure within the second chamber (204, 306, 406, 506, 606) to near vacuum; a valve assembly (212, 316, 416, 616) between the first chamber (202, 302, 402, 502, 602) and the second chamber (204, 306, 406, 506, 606) to isolate the pressure within the first chamber (202, 302, 402, 502, 602) from the pressure within the second chamber (204, 306, 406, 506, 606); a gas delivery system (206, 307) configured to introduce a processing gas into the first chamber (202, 302, 402, 502, 602) and to increase the pressure within the first chamber (202, 302, 402, 502, 602) to at least 10 atmospheres (1013250 Pa) while the processing gas is in the first chamber (202, 302, 402, 502, 602) and while the first chamber (202, 302, 402, 502, 602) is isolated from the second chamber (204, 306, 406, 506, 606); and a controller (122, 210) configured to operate the gas delivery system (206, 307) to introduce the processing gas into the first chamber (202, 302, 402, 502, 602) to process the layer on the substrate (314, 414), and open the valve assembly (212, 316, 416, 616) to enable the substrate (314, 414) to be transferred from the first chamber (202, 302, 402, 502, 602) to the second chamber (204, 306, 406, 506, 606). a first chamber (202, 302, 402, 502, 602); a pedestal (304, 404, 504, 604, 700) to support the substrate (314, 414), the pedestal (304, 404, 504, 604, 700) being positioned within the first chamber (202, 302, 402, 502, 602); a second chamber (204, 306, 406, 506, 606) at least partially surrounding the first chamber (202, 302, 402, 502, 602); a vacuum processing system configured to lower a pressure within the second chamber (204, 306, 406, 506, 606) to near vacuum; a valve assembly (212, 316, 416, 616) between the first chamber (202, 302, 402, 502, 602) and the second chamber (204, 306, 406, 506, 606) to isolate the pressure within the first chamber (202, 302, 402, 502, 602) from the pressure within the second chamber (204, 306, 406, 506, 606); a gas delivery system (206, 307) configured to introduce a processing gas into the first chamber (202, 302, 402, 502, 602) and to increase the pressure within the first chamber (202, 302, 402, 502, 602) to at least 10 atmospheres (1013250 Pa) while the processing gas is in the first chamber (202, 302, 402, 502, 602) and while the first chamber (202, 302, 402, 502, 602) is isolated from the second chamber (204, 306, 406, 506, 606); and a controller (122, 210) configured to operate the gas delivery system (206, 307) to introduce the processing gas into the first chamber (202, 302, 402, 502, 602) to process the layer on the substrate (314, 414), and open the valve assembly (212, 316, 416, 616) to enable the substrate (314, 414) to be transferred from the first chamber (202, 302, 402, 502, 602) to the second chamber (204, 306, 406, 506, 606). operate the gas delivery system (206, 307) to introduce the processing gas into the first chamber (202, 302, 402, 502, 602) to process the layer on the substrate (314, 414), and open the valve assembly (212, 316, 416, 616) to enable the substrate (314, 414) to be transferred from the first chamber (202, 302, 402, 502, 602) to the second chamber (204, 306, 406, 506, 606).