Determination of Some Kinetic Parameters of Fast Surface States in Silicon Single Crystals by Means of Surface Acoustic Wave Method

Abstract

The paper presents the acoustic method for determining some parameters of fast surface states in semiconductors. This method uses the interactions of the phonon-electron type for determining both the effective carrier lifetime τ influenced by the fast surface energetic states and the velocity g of the carrier trapped by the surface states. Some experimental results of the parameters τ and g in near-surface region of real Si(111) samples for their various surface treatments, obtained by the offered method, are presented.

The Application of Surface Acoustic Waves in Surface Semiconductor Investigations and Gas Sensors

“…This method is based on so-called interactions of the phonon-electron type [47] for determining both the effective carrier life-time influenced by the fast surface energetic states and the velocity g of the carrier trapped by the surface states.…”

“…The process of electrical carriers trapped in the surface states in a semiconductor, under the influence of a surface wave which propagates in a piezoelectric crystal, was considered in detail in the paper [47]. Figure 3 presents changes of electron attenuation in the external electric field Ed in the semiconductor.…”

“…heating in vacuum at ~600K; and (3) heating in steam at ~600K [47] In the case of the Si single-crystals at room temperature the parameter Sn is approximately equal to ~3·10 -16 cm 2 [1,6]. Therefore the surface concentration Nt of the fast surface states can be estimated in tested semiconductors.…”

“…of the drift field Ed; (SG -synchronous generator, CWG -continuous wave generator, FPS -forming packet system, AT -attenuator, OSC -digital oscilloscope) [47] The presented results concerning the plates of Si with the following parameters were obtained: …”

Photonic structures with grating couplers based on ZnO

“…Among wide band gap semiconductors, particularly zinc oxide ZnO is highly interesting [8], due to its very attractive properties and potential possibilities of applications in opto− electronic devices, especially in the range of ultraviolet and blue photonic structures including those with grating cou− plers, as well as in sensor structures [1,9,10]. Zinc oxide dis− plays the band gap of a high value E g~3 .4 eV.…”