Articles you may be interested inAmplification and surface topography in synchrotron radiation induced dry etching of Si with XeF2

ZnSeIZnMnSe MOW structures are grown by MBE. In situ RHEED control allows one to lock the growth cycle on the phase of the RHEED oscillations so that lattice plane completion is achieved independent of beam flux fluctuations and other irregularities. The band-edge resonant optical properties of the structures are dominated by sharp and pronounced excitonic features. The influence of strain and confinement on these excitons. their localization and interaction with phonons are discussed.

The topography of Si͑100͒ surfaces is investigated by scanning electron microscopy after generating replicas using photoinduced dry etching with radiation predominantly in the wavelength range between 105 and 122 nm. XeF 2 and Ar mixtures provide high selectivity with a structural resolution of about 100 nm. Pores and grains indicate that single photons initiate chain reactions with an amplification of 3ϫ10 5 . The overall quantum efficiency of removed Si atoms per incident photon above unity leads to a probability for stimulation of a reaction per incident photon of 6ϫ10 Ϫ5 . Addition of O 2 increases the amplification factor, reduces the excitation probability, and causes a reduced selectivity at high irradiation intensity.

Microstructuring of Si with XeF2 can be optimized by increasing the contrast in choosing a wavelength with minimal nonselective etching. The efficiency of selective etching with optimal quality can be increased by factors of 100 and 500 by using wavelengths around 120 and 110 nm, respectively, in comparison to longer wavelengths around 200 nm. The high efficiency of typically 10 removed atoms per photon, the availability of optical materials for imaging and the potentially high spatial resolution at 120 nm compared to the conventional excimer laser and I-line wavelengths present a perspective for generating line densities required in the Gbit range.

No abstract