Chemical Vapor Deposition of Metal Borides, 4: The Application of Polyhedral Boron Clusters to the Chemical Vapor Deposition Formation of Gadolinium Boride Thin-film Materials

✍ Scribed by Shreyas S. Kher; Yexin Tan; James T. Spencer

• Publisher: John Wiley and Sons
• Year: 1996
• Tongue: English
• Weight: 1009 KB
• Volume: 10
• Category: Article
• ISSN: 0268-2605
• DOI: 10.1002/(sici)1099-0739(199604)10:3/4<297::aid-aoc460>3.0.co;2-d

✦ Synopsis

The chemical vapor deposition of high-quality polycrystalline thin films of gadolinium hexaboride, GdB,, was achieved through the vacuum copyrolysis of gas-phase boron hydride clusters, such as nido-pentaborane(9) [B,H,] and nidodecaborane( ) [BI&],

and gadolinium(II1) chloride. These films typically displayed deep blue colors, were very hard and adhered very well to most deposition substrates. Depositions were carried out on a variety of substrates including quartz, copper, silicon, SiOl and ceramic materials. X-ray diffraction and scanning electron microscopic data showed the formation of highly crystalline materials with a strongly preferred orientation in the (111) direction. Attempted depositions of gadolinium boride films on CaFJ111) resulted in the apparent formation of a ternary (Ca/Gd)B, phase in which the calcium is presumably substituted for gadolinium atoms in the cubic GdB, structure. The gadolinium boride thin films were investigated by scanning electron microscopy (SEM), X-ray emission spectroscopy (XES), X-ray diffraction (XRD), and glow-discharge mass spectrometry (GDMS). GDMS showed that the GdB, films were relatively uniform in composition in the bulk material.