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High-purity metal sputtering target is one of the key basic materials for integrated circuits. Self-dependence of the sputtering targets is vital for the high-quality development of the integrated circuit industry in China. This study analyzes the application demand for and development status of high-purity metal sputtering targets for integrated circuits, involving high-purity aluminum and aluminum alloys, high-purity copper and copper alloys, high-purity titanium, high-purity tantalum, high-purity cobalt, high-purity nickel platinum, and high-purity tungsten and tungsten alloys. Moreover, it summarizes the challenges regarding the key manufacturing technologies and engineering application of high-performance sputtering targets in China and proposes several major development directions based on the development goals of the field by 2030. Specifically, China needs to improve its material processing technologies, focus on the key technologies for high-performance target processing, develop high-end new materials according to frontier demands, and improve the capabilities of material analysis, testing, and application evaluation. Furthermore, the following suggestions are proposed: establishing an industry-education-research-application system, realizing the domestic manufacturing of key equipment, strengthening talent team construction, establishing an independent intellectual property system, and expanding international exchange and cooperation,thereby promoting the development quality and level of high-purity metal sputtering targets.

Innovating coal development and utilization technology to reduce carbon emissions during the whole life cycle of coal from production to utilization is a coal-based clean energy route that meets the characteristics of China's energy endowments. Underground gasification is one of the potential methods of deep coal in-situ mining, coupled with CCS/CCUS (Carbon Capture and Storage/Carbon Capture, Utilization and Storage) deep coal underground gasification hydrogen production technology route can not only utilize the rich deep coal resources, but also is expected to become an ideal of coal-based low-cost hydrogen production route. Based on the world's only kilometer-level deep coal underground gasification test data, combined with Aspen Plus process simulation, the carbon emission accounting and carbon emission reduction potential analysis of deep coal underground gasification hydrogen production were carried out. Compared with the commercial ground Lurgi fixed bed pressurized gasification hydrogen production route, the life cycle assessment method is used to establish the whole life cycle carbon emission calculation model of the two processes, compared the life cycle carbon emissions of the two hydrogen production routes.The CCS/CCUS path and carbon emission reduction potential of the underground gasification of deep coal are further evaluated.The results show that the carbon emissions during the life cycle of underground gasification of deep coal and ground gasification of Lurgi coal are 3.29×109 t CO2-eq and 3.93×106 t CO2-eq in the case of hydrogen production capacity of 1.2 billion Nm3/a, respectively, and the carbon dioxide directly emitted into the atmosphere in the form of exhaust gas is 2.09×106 t and 2.24×106 t, respectively. The main carbon emitters in the hydrogen production phase are exhaust gases, including exhaust gases from acid gas removal units and flue gases from methane reforming units. The high methane content characteristics brought about by the underground gasification process of deep coal lead to the CO2 emissions contributed by the flue gas of the methane reforming unit to 8.84 kg when producing 1 kg of hydrogen.In terms of indirect emissions, deep coal underground gasification directly uses liquid water as a gasifier without consuming external steam, so the carbon emissions caused by steam consumption are lower than that of ground gasification. The upstream of Lurgi coal surface gasification includes the coal mining and processing and coal transportation stages, and although the carbon emissions in these two phases are only 6.7%, but still bring 2.63×105 t CO2-eq. If the deep coal underground gasification cavity is used for CO2 geological storage under the premise of geological safety risk assessment, the storage capacity can reach 61.8% of the total carbon emissions, and if the urea device is supported by 470,000 tons / year, the remaining CO2 can be effectively used,to form a near-zero emission deep coal underground gasification hydrogen production and urea co-production technical route. The research results provide a scientific basis for quantitative evaluation of carbon emissions for hydrogen production from deep coal underground gasification.

China has rich reserves of deep coal resources, and underground coal gasification can transform coal into gas and transport it to the ground, which is an important way for in-situ fluidized mining of deep coal.This article introduces the development history and technical status of underground coal gasification technology (UCG), as well as typical cases of underground coal gasification in the middle and deep parts.Based on the modern underground coal gasification technology system, the key technologies and technical research directions of deep underground coal gasification was analyzed and the prospect of deep coal gasification mining with the goal of natural gas production was outlooked.The development trend of UCG is from the mine type to the drilling type, from shallow coal seams to deep coal seams, from single power generation to comprehensive utilization.The practice of UCG in the middle and deep coal seams has verified the technical feasibility.The key technologies of deep underground coal gasification mainly include geological evaluation and scientific site selection, gasifier construction, deep coal seam high-pressure ignition, controllable mobile injection and deep fire zone geophysical detection.Deep coal gasification to produce natural gas can not only realize the clean and efficient use of deep coal resources, but also solve the contradiction between supply and demand caused by the increase in natural gas consumption.