We report a high density MgO ceramic substrate produced by the tape casting technology. The tape casting formulation and process produced a uniform tape free of cracking. Y₂O₃ and SiO₂ were used as the sintering aid for the pressureless sintering of the green tape. X‐ray diffraction phase identification indicates that MgO is the main phase, while both Y₂O₃ and SiO₂ sintering aids react with MgO to form MgY₄Si₃O₁₃ as the second phase. Liquid phase sintering occurs in the temperature range from 1030°C to ~1500°C, which is confirmed by the simultaneous Thermal Gravitation Analysis/Differential Scanning Calorimeter (TGA/DSC) and the percent linear shrinkage and densification. A 96.5% theoretical density was achieved by presureless sintering at 1650°C for 2 hours, which was further increased to a fully dense structure using hot‐isostatic‐pressing(HIP) at 1650°C and 207 MPa in argon. Scanning electron microscopy (SEM) and energy dispersive(EDS) spectroscopic analysis on the HIP’ed sample show that MgY₄Si₃O₁₃is located at the MgO grain boundary and the sample has a fully dense structure. The refractive indices and extinction coefficient were measured on the HIP’ed sample along with thermal properties and dielectric properties. Thermal diffusivity and heat capacity were measured to calculate the thermal conductivity.

中文翻译：

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带状铸造和MgO陶瓷的表征

我们报告了通过流延铸造技术生产的高密度MgO陶瓷基板。胶带流延配方和工艺产生了无裂纹的均匀胶带。Y ₂ O ₃和SiO ₂用作生带的无压烧结的烧结助剂。X射线衍射相识别表明，MgO是主要相，而Y ₂ O ₃和SiO ₂烧结助剂均与MgO反应形成MgY ₄ Si ₃ O ₁₃作为第二阶段。液相烧结发生在1030°C至〜1500°C的温度范围内，这通过同时进行的热引力分析/差示扫描量热仪（TGA / DSC）以及线性收缩率和致密化百分比来确认。通过在1650°C下进行2秒钟的无定形烧结可获得96.5％的理论密度，然后在1650°C和207 MPa的氩气中通过热等静压（HIP）将其进一步提高为完全致密的结构。对HIP样品的扫描电子显微镜（SEM）和能量色散（EDS）光谱分析表明，MgY ₄ Si ₃ O ₁₃MgO位于MgO晶界，样品具有完全致密的结构。在HIP处理过的样品上测量折射率和消光系数以及热性能和介电性能。测量热扩散率和热容量以计算热导率。