Surface morphology by reflectivity of coherent X-rays
详细信息 查看全文
- 作者：I. K. Robinson ; J. A. Pitney ; J. L. Libbert ; I. A. Vartanyants
- 刊名：Physica B
- 出版年：1998
- 出版时间：15 June 1998
- 年：1998
- 卷：248
- 期：1-4
- 页码：387-394
- 全文大小：182 K
文摘
Coherent X-ray diffraction (CXD) is a new technique made possible by the enhanced brilliance specifications of hard X-ray wigglers and undulators, especially at third-generation synchrotron radiation sources. CXD differs from conventional diffraction in that it uses a microscopic beam that is close to fully coherent one. The resulting diffraction pattern is related to the Fourier transform of the entire object illuminated by the beam, and hence is sensitive to any fluctuations within it, whether these are in space or in time. We have observed CXD effects in the near-specular reflectivity from silicon wafers. We introduce a simple theoretical formalism for explaining the origin of the coherent diffraction signal in a reflectivity experiment, in which we find a slow but distinct evolution of the pattern with the perpendicular component of momentum transfer, qz. We demonstrate a practical energy dispersive method of measuring this qz-dependence.