高导热AIN陶瓷材料制造及其应用研究

对AIN陶瓷材料制备过程中影响其性能尤其是导热性能的诸多因素进行实验，摸索出一套较合理的制备工艺，制造出性能较稳定，导热率高的AIN陶瓷材料，观察了AIN陶瓷的微结构并得出某些结论。已加工出AIN陶瓷夹持杆，收集极和输出窗，在微波管上试用，取得一些经验。     

陶瓷材料

9912754含压电片梁的振动控制[刊]/林西强//国防科技大学学报.—1999,21(2).—25～28(A)9912755氮化铝陶瓷材料[刊]/黄岸兵/微电子技术.—1999,27(2).—22～29(V)本文介绍了 AIN 陶瓷基片生产的关键技术,国内外 AIN 陶瓷封装概况。探讨了 AIN 陶瓷封装发展的趋势。参7     

混合多层布线用AIN共烧多层基板技术研究

大功率混合多层基板（AIN混合多层布线基板）是采用在AIN共烧多层陶瓷基板上制作薄膜多层布线而形成的。其优良的散热性，高的信号传输速度，以及良好的高频特性，完全能够在微波功率器件和高速数字电路中使用。然而AIN混合多层布线基板的应用，离不开高性能的AIN共烧多层基板。本文仅对AIN共烧多层基板制作过程中需要解决的几个关键技术方面进行了研究，取得了一定的成果。     

AIN多层基板的研制

MCM技术推动了现代微电子技术迅猛发展，已广泛应用于各种通讯系统的收发组件之中。AIN基板作为MCM技术多层基板主流之一，由于其高热导率、与硅片匹配的热膨胀系数、高介电常数、兼容各种芯片组装工艺的优点，在各个领域均获得了广泛的应用。文章结合一个微波组件AIN基板的研制，阐述了在AIN基板研制过程中解决的工艺难点，如粉料配制、流延、层压、烧结等，对研制的AIN基板进行了物理性能与电性能测试，结果表明AIN基板完全可以满足大功率毫米波／微波组件的实用化要求。     

AlN多层基板的研制

MCM技术推动了现代微电子技术迅猛发展,已广泛应用于各种通讯系统的收发组件之中。AIN基板作为MCM技术多层基板主流之一,由于其高热导率、与硅片匹配的热膨胀系数、高介电常数、兼容各种芯片组装工艺的优点,在各个领域均获得了广泛的应用。文章结合一个微波组件AIN基板的研制,阐述了在AIN基板研制过程中解决的工艺难点,如粉料配制、流延、层压、烧结等,对研制的AIN基板进行了物理性能与电性能测试,结果表明AIN基板完全可以满足大功率毫米波／微波组件的实用化要求。     

用于GaAs贯穿注入和包封退火的AIN薄膜

用直流反应溅射淀积的AIN薄膜作包封介质对GaAs进行了贯穿注入和包封退火。用电化学C－V法测量了载流子的分布。实验结果与TRIM模拟结果符合得很好。用50nm的AIN包封进行贯穿注入和退火，得到了较小的标准偏差，较陡峭的载流子分布和较高的激活率。应用AIN包封层后，当注入能量180keV，注入剂量7．5×10~13cm~－2时，所得到的最高载流子浓度为1．84×10~18cm~－3，样品方块电阻为118Ω／□。     

氮化铝陶瓷材料

本文介绍了AIN陶瓷基片生产的关键技术,国内外AIN陶瓷封装概况。探讨了AIN陶瓷封装发展的趋势。     

氮系Ⅲ—Ⅴ族化合物—A1N

AIN薄膜是一种高温绝缘膜和半导体器件的钝化膜,特别适用于超高频表面波器件,是有很大的应用潜力和发展前景的材料。本文主要介绍AIN薄膜的特性、制备方法和应用。     

用于高温压力传感器的AIN绝缘膜的研究

采用直流磁控反应溅射法制备了高温压力传感器用的AIN薄膜。用X射线衍射对薄膜的晶向结构进行了分析，研究了薄膜的绝缘特性和化学稳定性，分析了AIN与Si的热膨胀系数、热导系数的关系。选用AIN在力敏电阻条和硅弹性膜之间进行绝缘隔离，由于无p-n结，力敏电阻无反向漏电，得到了极好的压力传感器特性，即零点电漂移及热漂移小及非线性小。     

可靠的AIN金属化

在过去两年，AIN陶瓷作为电子封装材料增长迅速。但AIN要实用化，要广泛地进入电子市场，则需要可靠的金属化系统。Carborundum公司已研制成功并推出大批量生产的致密的、高附着强度的金属化系统。这种薄膜金属化系统与AIN基板形成的粘接比陶瓷本身还牢固。     

AlN陶瓷封装的研究现状

介绍了氮化铝（ＡｌＮ）陶瓷在微电子器件高可靠封装中的应用现状及前景。     

氮化铝陶瓷的氧化机理研究

本文研究了不同氧化处理下氮化铝陶瓷的氧化情况,并使用Mo-Mn法进行金属化,测试封接强度及气密性,从而探究氮化铝瓷的氧化机制,氮化铝基瓷与氧化层之间的结合。结果表明:经过1100℃/1h高温氧化处理,氮化铝陶瓷表面几乎没有氧化。在1250℃/1h、1250℃/2h,表面生成了氧化铝,氧化层主晶相为AlN与Al2O3;在1350℃/1h下,氧化层主晶相为Al2O3;氧化层表面有明显的裂纹,均漏气。对不同处理后的氧化铝层表面进行Mo-Mn法金属化,当氧化层厚度较薄时,断裂发生在氧化层。氮化铝瓷与氧化铝层之间的结合机理可能是在两者之间产生了AlON等中间物,从而实现了氮化铝瓷与氧化层之间牢固的连接。     

Preparation of Oriented Aluminum Nitride Thin Films on Polyimide Films and Piezoelectric Response with High Thermal Stability and Flexibility

c‐Axis oriented aluminum nitride (AlN) thin films are successfully prepared on amorphous polyimide films by radiofrequency magnetron reactive sputtering at room temperature. Structural analysis shows that the AlN films have a wurtzite structure and consist of c‐axis oriented columnar grains about 100 nm wide. The full width at half maximum of the X‐ray diffraction rocking curves and piezoelectric coefficient d₃₃ of the AlN films are 8.3° and 0.56 pC N^–1, respectively. The AlN films exhibit a piezoelectric response over a wide temperature range, from –196 to 300 °C, and can measure pressure within a wide range, from pulse waves of hundreds of pascals to 40 MPa. Moreover, the sensitivity of the AlN films increases with the number of times it was folded, suggesting that we can control the sensitivity of the AlN films by changing the geometric form. These results were achieved by a combination of preparing the oriented AlN thin films on polyimide films, and sandwiching the AlN and polymer films between top and bottom electrodes, such as Pt/AlN/polyimide/Pt. They are thin (less than 10 μm), self powered, adaptable to complex contours, and available in a variety of configurations. Although AlN is a piezoelectric ceramic, the AlN films are flexible and excellent in mechanical shock resistance.     

MCM用氮化铝共烧多层陶瓷基板的研究

通过实验优化AlN(氮化铝)瓷料配方及排胶工艺,对共烧W(钨)导体浆料性能及AlN多层基板的高温共烧工艺进行了研究,并对AlN多层基板的界面进行了扫描电镜分析。采用AlN流延生瓷片与W高温共烧的方法,成功地制备出了高热导率的AlN多层陶瓷基板,其热导率为190 W/(m·K),线膨胀系数为4.6106℃1(RT~400℃),布线层数9层,W导体方阻为9.8 m,翘曲度为0.01 mm/50 mm,完全满足高功率MCM的使用要求。     

Spontaneous growth of GaN nanowire nuclei on N- and Al-polar AlN: A piezoresponse force microscopy study of crystallographic polarity

The polarity of gallium nitride (GaN) nanowire nuclei grown on AlN layers was studied by piezoresponse force microscopy (PFM). N- or Al-polar AlN layers were grown by molecular beam epitaxy (MBE) on Si (111) substrates by use of Al- or N-rich growth conditions, respectively. Short and low density GaN nanowires were then grown on each AlN polarity type. PFM measurements verified the expected AlN layer polarity and further indicated that predominantly N-polar nanowires are produced for growth on both AlN polarity types. Cross-section scanning transmission electron microscopy (STEM) images further reveal that the nanowires on Al-polar AlN films are nucleated on regions in the AlN layer that contain inversion domains, which propagate into the GaN nanowire nuclei. PFM measurements were found to be a convenient technique for mapping the polarity of a statistically significant number of individual GaN nanowires.     

Investigation of three-step epilayer growth approach of GaN films to minimize compensation

The heteroepitaxial growth of gallium nitride (GaN) films using three distinct growth steps is investigated in terms of improving the electrical properties of the layer. The first step involves the deposition of a fixed quality aluminum nitride (AlN) layer on an a-plane sapphire substrate. The second step is aimed at maximizing the GaN grain size initially grown on the AlN. The third step is aimed at optimizing the surface morphology of the GaN layer. The means of transitioning the growth between steps is investigated and an optimum transition method is reported. Growth parameters investigated include pressure, trimethylgallium molar flow rate, and ratio of group V to group III precursor molar flows. Carrier statistics show a lower level of compensation in films grown at a slower growth rate in the second step and a moderate rate in the third step.     

Ammonothermal synthesis of aluminum nitride crystals on group III-nitride templates

Polycrystalline aluminum nitride (AlN) crystals were synthesized using the ammonothermal technique at temperatures between 525°C and 550°C. The growth of AlN was conducted in alkaline conditions with potassium azide (KN₃) as the mineralizer. The growth mechanism was found to be reversegradient soluble, necessitating the placement of the GaN and AlN seeds at a higher temperature than the aluminum metal source. Growth on the GaN seeds varied from 100 to 1500 μm in thickness at a gestation period of 21 days. Additionally, scanning electron micrographs revealed varying microstructure ranging from pointed hexagonal rods, which are approximately 5 μm wide and 20 μm long, to highly densified and contiguous films. Formation of hexagonal AlN was verified using x-ray powder diffraction measurements. Oxygen was detected at 3.7 at.% by inert gas fusion analysis on AlN nucleated on the walls of the autoclave and a qualitative indication of unintentionally incorporated impurities in the AlN grown on the GaN seeds was obtained using energy-dispersive x-ray analysis. Photoluminescence spectroscopy conducted at 20 K revealed a deep-level emission at 3.755 eV due to unintentionally incorporated impurities.     

不锈钢表面溅射氮化铝陶瓷膜工艺参数的研究

工业生产中需要测量机械零件的润滑油膜厚度,利用超声波检测可实现无损检测的目的。利用氮化铝(AlN)陶瓷膜制成的压电换能器对超声波发射和接收。利用射频磁控溅射技术,在不锈钢表面沉积AlN薄膜。利用X线衍射仪(XRD)和原子力显微镜(AFM)等设备对AlN薄膜结构表征,并对结果进行了讨论。     

Comparison of various buffer schemes to grow GaN on large-area Si(111) substrates using metal-organic chemical-vapor deposition

A comparison of gallium-nitride (GaN) films grown on large-area Si(111) using a single aluminum-nitride (AlN) buffer, an AlN/graded-Al_xGa_1−xN buffer, and the introduction of additional low-temperature (LT)-grown AlN interlayers is reported. A graded-AlGaN buffer followed by additional LT-AlN interlayers is shown to completely eliminate cracking in nitride films of thickness >2 μm and also reduce the threading-dislocation density significantly. A partial compensation of GaN-tensile strain by the compressive-lattice strain induced by the AlGaN and AlN layers is responsible for this effect. The surface roughness is increased by the introduction of the LT-AlN buffers.     

Polarity Analysis of Self-Seeded Aluminum Nitride Crystals Grown by Sublimation

Self-seeded aluminum nitride (AlN) crystals were successfully grown in a tungsten crucible by the sublimation method. The polarities along the growth direction of these AlN samples were characterized by chemical etching, combined with high-resolution transmission electronic microscopy (HRTEM) and Raman spectroscopy. It has been proven by our experimental results that etching in KOH solution and in molten KOH-NaOH can be a reliable method to determine the surfaces with different polarities. Chemically active N-polar (0001) AlN surfaces were removed appreciably, while only etch pits related to threading dislocations were observed on Al-polar surfaces after chemical etching. HRTEM images revealed that there are noticeable inversion domain boundaries in the samples. Raman spectrum measurements showed the vibration mode change before and after etching in the same geometrical arrangement.