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为满足太阳能电池对高迁移率透明导电氧化物薄膜的需求，本工作提出一种利用ZrO2、CeO2、Ta_2O5和TiO2多组分共掺杂方案，制备In_2O3基陶瓷靶材(IZCTO)，并研究烧结温度和时间对靶材结构与性能的影响。结果表明，IZCTO靶材呈现单一立方铁锰矿In_2O3相结构，具有细小致密堆积的晶粒及均匀的元素分布。随着烧结温度升高和保温时间延长，靶材中的气孔得到有效消除，致密性显著提升。尤其在1550℃烧结6 h后，靶材的综合性能达到优异水平，其相对密度高达99.35%，电阻率低于1.181×10–3Ω·cm。因此，本工作设计及制备的IZCTO靶材可为磁控溅射沉积高迁移率TCO薄膜提供研究基础。
Abstract：Introduction Silicon heterojunction(SHJ) solar cells have a high conversion efficiency, which drives the development of the photovoltaic industry. The transparent conductive oxide(TCO) films with a high electron mobility are needed to improve the conversion efficiency of SHJ solar cells. The mobility of the conventional 10%(in mass) SnO2 doped In_2O3 films is 30 cm2/(V·s), which cannot meet the demand of high mobility. Some reports indicate that the Ce, Ti, Zr, W, Hf, Mo, and Ta dopants with a low doping content can improve the mobility. A high density ceramic target is a key material for depositing TCO films. However, a low doping content is unconducive to sintering densification of ceramic target. Therefore, multiple oxide dopants with harmless sintering additive are used to enhance sintering densification and decrease resistivity. In this paper, an In_2O3-based ceramic target doped with ZrO2, CeO2, Ta_2O5, and TiO2 was designed, and CeO2 and TiO2 were acted as sintering additives. In addition, the phase structure, microstructure, density, and resistivity of targets sintered at different sintering temperatures and times were also investigated. Methods High purity(99.99%) In_2O3, CeO2, Ta_2O5, ZrO2, and TiO2 nanopowders were used as raw materials. The doping contents of CeO2, Ta_2O5, ZrO2, and TiO2 powders were 0.3%, 0.3%, 0.3% and 0.1%, respectively. Anhydrous ethanol was used as a dispersant, and the weight ratio of zirconia balls to powders was 3:1. The slurry was ground in a planetary ball mill at 360 r/min for 6 h, and then dried at 80 ℃ for 24 h. The dried powders were added with polyvinyl alcohol(PVA) at 5% aqueous solution, and then granulated through an 80-mesh sieve. The granulated powders were pressed into green bodies with a relative density of approximately 58%, a diameter of 13 mm, and a thickness of 1.5 mm. The green bodies were dewaxed at 600 ℃ for 3 h and then sintered in an oxygen atmosphere at a flow rate of 5 L/min. The targets were sintered at 1400, 1450, 1500, 1500 ℃ and 1600 ℃ for 4 h and 6 h, respectively. The phase structure was analyzed by X-ray diffraction(XRD). The microstructure and elemental distribution were characterized by field-emission scanning electron microscopy(FE-SEM). The grain size and distribution were analyzed and statistically calculated from FE-SEM images using a software named Nano measure. The density was determined based on the Archimedes principle. The resistivity was evaluated using a four-point probe. The sintering densification behavior during the heating process was investigated by a dilatometric analyzer. Results and discussion The densification and shrinkage of target during heating process can be divided into three stages. The target exhibits a rapid shrinkage after 1324 ℃, and its shrinkage rate at 1500 ℃ is 10.7%. This confirms the sintering additive function of dopants. The XRD patterns show the formation of a cubic bixbyite phase, indicating that Ce4+, Zr4+, Ta5+ and Ti4+ are dissolved in the lattice of In_2O3. The grains are densely packed together, and the grain size gradually increases with increasing sintering temperature and holding time. All the targets show a dense internal microstructure and transgranular fracture behavior. The average grain size of targets sintered for 4 h increases from 1.44 μm at 1400 ℃ to 5.31 μm at 1600 ℃. A more substantial increase also occurs from 1.95 μm at 1400 ℃ to 10.41 μm at 1600 ℃ in the targets sintered for 6 h. Elements Ce, Ta, Zr and Ti exhibit a uniform distribution in In_2O3 matrix, which helps to suppress an abnormal discharge during magnetron sputtering. The density of targets sintered for 6 h is higher than that of targets sintered for 4 h. The density firstly increases and then decreases as the sintering temperature increases from 1400 ℃ to 1600 ℃. The optimal density of targets sintered for 4 h and 6 h is 99.05% and 99.39%, respectively. The resistivity of targets sharply decreases when the sintering temperature increases from 1400 ℃ to 1500 ℃, and then slightly increases with further increasing sintering temperature to 1600 ℃. The optimal resistivity of targets sintered at 1500 ℃ for 4 h and 6 h is 1.214×10–3 Ω·cm and 1.181×10–3 Ω·cm, respectively. The resistivity increase of target sintered at 1600 ℃ is due to the volatilization of In_2O3 and density decrease of target at a high sintering temperature. Conclusions This work investigated the effects of sintering temperature and time on the microstructure and properties of In_2O3-based targets doped with CeO2, Ta_2O5, ZrO2, and TiO2. The results showed that all the targets have single cubic bixbyite phase, dense microstructure. The transgranular fracture characteristics and uniform grains with sizes of <10 μm could be obtained. The doped multiple oxides exhibited a sintering additive function, promoting sintering densification. The sintering densification process could be accelerated after 1324 ℃. Raising sintering temperature and prolonging holding time could effectively improve the density and reduce the resistivity. The target sintered at 1550 ℃ for 6 h had a relative density of over 99% and a resistivity of less than 1.181×10–3 Ω·cm. Therefore, multiple oxides doped In_2O3-based targets with a low doping content could achieve high density and conductivity.
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基本信息:
DOI：10.14062/j.issn.0454-5648.20250200
中图分类号:TQ174.1
引用信息:
[1]李婷,吴芳洲,许积文,等.多组分共掺杂In_2O_3基陶瓷靶材的显微结构与电性能[J].硅酸盐学报,2026,54(03):1063-1071.DOI:10.14062/j.issn.0454-5648.20250200.
基金信息:
国家自然科学基金区域创新发展联合基金（U21A2065）; 国家自然科学基金（62464004）; 广西科技重大专项（AA21077018）
2026-02-10
2026-02-10
2026-02-10