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软X射线多层膜经常在强光束的照射下,做为反射镜使用。由于同步辐射等强光束携带很高的能量,使软X射线多层膜镜在工作时的温升可达几百度。软X射线多层膜为亚稳结构,周期仅为纳米量级,如此高的温升会对其周期结构造成不同程度的破坏,从而使反射率降低,反射率峰值位置漂移。因此,研究软X射线多层膜的结构热稳定性,对寻求软X射线多层膜的结构稳定性的改善方法具有重要意义。本文通过对Co/C,CoN/CN软X射线多层膜的周期结构热稳定性的对比研究,发现掺杂N可以十分有效地改善Co/C软X射线多层膜的周期结构热稳定性。

Frequency responses of modulated electroluminescence (EL) of light-emitting diodes were measured using a testing setup. With increasing frequency of the ac signal, the relative light intensity (RLI) clearly decreases. Furthermore, a peculiar asynchrony between the RLI and ac small-signal is observed. At frequencies higher than 10kHz, the RLI clearly lags behind the ac signal and the absolute value of the lagging angle is nearly proportional to the signal frequency. Using the classical recombination model of light-emitting diodes under ac small-signal modulation, these abnormal characteristics of modulated EL can be clearly explained.

We report a significant increase of the reflectivity of a soft X-ray Co/C multilayer at grazing incidence after low temperature annealing. By monitoring the enhancement of the first order modulation peak on annealing, the effective interdiffusion coefficient as low as -10－25ｍ2ｓ－1 has been measured,which is nearly equal to the true macroscopic interdiffusion coefficient as the modulation wavelength of the Co/C multilayer studied is well above the critical wavelength. The negative true macroscopic interdiffusion coefficient indicates that there is a tendency to phase separation in the Co-C system, which can be interpreted as the positive enthalpy of mixing calculated based on Miedema′s macroscopic atom model. The decrease of reflectivity above some anneal temperature is also discussed and explained as the competition between interfacial sharpness and roughness.