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Study of thin films of mixed uranium oxides/nitrides by Photoemission and AES. Films have been prepared by reactive sputter deposition in an Ar plasma in presence of N2 and O2 admixtures. Aim: elucidate if a solid solution of UO and UN (known as uranium oxynitride UNxO1-x) can form by this synthesis method. Such ternary oxide has been described for bulk compounds. Since sputter deposition can produce very finely dispersed systems, this looked like a good method for producing the oxynitride. Oxynitride has uranium in a low oxidation state (UN: formally 3; UO: formally 2). Initially UN films with an increasing oxygen content were deposited. ). The oxynitride is metallic and it can be ashat the U5f are still itinerant and pinned the EF: for UN they are and for UO they also should be. We studied whether the oxygen incorporation goes along with a DOS at EF (pointing to UO formation) or whether it simply leads to the formation of the UO2 semiconductor (no DOS at EF)- Experiment: The series started with deposition of UN and then increasing gradually the O2 pressure. U4f, O1s and VB spectra (by HeII). Also Auger spectra of U, O and N were taken. Depositions were done at room temperature and elevated temperature. We searched for the onset of UO2 formation (characteristic U4f peak), because at sufficiently high O2 pressure this oxide will form – oxygen simply displaces nitrogen. File Format: Files are stored in the VAMAS format. This is a universal formed used by commercial data analysis programs such as CasaXPS. Description of the VAMAS format can by found in the internet

本研究采用光发射谱（Photoemission）与俄歇电子能谱（AES）对混合铀氧化物/氮化物薄膜展开分析。薄膜通过反应溅射沉积法制备，沉积过程在氩（Ar）等离子体环境中进行，并掺入氮气（N₂）与氧气（O₂）。本研究的目标为阐明：通过该合成方法能否生成UO与UN的固溶体（即铀氧氮化物UNₓO₁₋ₓ）。此类三元氧化物在块体材料中已有文献报道。由于溅射沉积可制备高度分散的体系，该方法被视为制备铀氧氮化物的优选路径。该氧氮化物中的铀处于低氧化态：UN中铀的形式氧化态为+3，UO中为+2。实验初始阶段，先制备氧含量逐步升高的UN薄膜。该氧氮化物为金属性，其铀的5f电子仍处于巡游态并钉扎于费米能级（EF）：UN体系中该5f电子为巡游态，UO体系中亦应如此。我们研究了氧掺入后，究竟是会在费米能级处出现态密度（DOS，指向UO的生成），还是仅会生成二氧化铀（UO₂）半导体（费米能级处无态密度）。实验流程：首先沉积UN薄膜，随后逐步提高氧气分压。采用HeII光源采集U4f、O1s及价带（VB）光谱，同时采集U、O、N的俄歇电子能谱。沉积过程分别在室温与高温环境下开展。我们通过特征U4f峰来识别UO₂的生成起始点，因为当氧气分压足够高时，氧气会取代氮元素，从而生成二氧化铀。文件格式：所有数据均以VAMAS格式存储，该格式为商用数据分析软件（如CasaXPS）所通用的标准格式。VAMAS格式的详细说明可通过互联网查询获取。