The epitaxial growth of AlN and GaN layers is investigated using metalorganic vapor-phase epitaxy on a Si(100) substrate, on the surface of which a V-shaped nanostructure with elements of sub-100-nm size (NP-Si(100) substrate) is formed. It is shown that a corrugated surface is formed from semipolar AlN(10 $$\bar {1}$$ 1) planes with opposite axes of symmetry c during the formation of a semipolar AlN layer at the initial stage of epitaxy. Then, during the growth of the GaN layer, the transition from the symmetric state of two semipolar AlN planes to an asymmetric state with a single orientation of the c axis of the semipolar GaN(10 $$\bar {1}$$ 1) layer occurs, and the c direction in the growing semipolar layer coincides with the direction of the flow of $${\text{N}}_{2}^{ + }$$ ions to the silicon surface during the formation of a nanomask.

The epitaxial growth of AlN and GaN layers was studied by Metalorganic Vapor Phase Epitaxy, on a Si(100) substrate, on the surface of which a V-shaped nanostructure with sub-100 nm element size (NP-Si(100)) was formed. It is shown that a corrugated surface is formed from semipolar AlN(10-11) planes with opposite "c"axes during the formation of a semipolar AlN layer at the initial stage of epitaxy. Then, during the growth of the GaN layer, the transition from the symmetric state of two semipolar AlN planes to an asymmetric state with a single orientation of the "c"-axis of the semipolar GaN(10-11) layer occurs, and the "c" direction in the growing semipolar layer coincides with the direction of the flow of N2+ ions to the silicon surface during the formation of a nanomask.

AbstractSemipolar GaN layers synthesized on a nanostructured Si(100) substrate are studied. It is shown that using a Si(100) nanoprofile combined with Si_ x N_ y nanostrips on top of nanostructures can yield, via metal-organic chemical-vapor deposition, GaN(10 $$\bar {1}$$ 2) layers. An additional SiC buffer layer makes it possible to obtain GaN(10 $$\bar {1}$$ 1) layers with a full-width at half-maximum of the diffraction-curve of ω_θ ≈ 35′ arcmin. It is found that the luminescence properties of the semipolar layers are mostly due to basal plane stacking faults BSF_ S -I_1, in contrast to polar layers in which these properties are mostly due to the recombination of excitons.

Semipolar GaN layers synthesized on a nanostructured Si(100) substrate are studied. It is shown that using a Si(100) nanoprofile combined with SixNy nanostrips on top of nanostructures can yield, via metal-organic chemical-vapor deposition, GaN(10 $$\bar {1}$$ 2) layers. An additional SiC buffer layer makes it possible to obtain GaN(10 $$\bar {1}$$ 1) layers with a full-width at half-maximum of the diffraction-curve of ωθ ≈ 35′ arcmin. It is found that the luminescence properties of the semipolar layers are mostly due to basal plane stacking faults BSFS-I1, in contrast to polar layers in which these properties are mostly due to the recombination of excitons.

AbstractWe propose a new method for growing semipolar GaN films on a Si(100) substrate with an array of sub-100-nm-sized V-grooves formed on the surface. It is shown that, using such a nanostructured substrate for metalorganic hydride vapor-phase epitaxy, it is possible to obtain GaN (101̅1̇) epilayers deviating by an angle of about 62° from the polar direction and having an X-ray rocking curve with a minimum FWHM value of ω_θ ~ 60 arcmin.

We propose a new method for growing semipolar GaN films on a Si(100) substrate with an array of sub-100-nm-sized V-grooves formed on the surface. It is shown that, using such a nanostructured substrate for metalorganic hydride vapor-phase epitaxy, it is possible to obtain GaN (101̅1̇) epilayers deviating by an angle of about 62° from the polar direction and having an X-ray rocking curve with a minimum FWHM value of ωθ ~ 60 arcmin.

We report a detailed numerical simulation of the reflection of visible light from a sub-wavelength grating with a rectangular profile on the silicon surface. Simulation is carried out by the effective refractive index method and rigorous coupled-wave analysis. The dependences of the reflectance on the grating depth, fill factor and angle of incidence for TE and TM polarisations are obtained and analysed. Good agreement between the results obtained by the two methods for grating periods of similar to 100 nm is found. The possibility of reducing the polarised light reflectance to about 1 % by adjusting the depth and the grating fill factor is demonstrated. The characteristics of the Brewster effect manifestation (pseudo-Brewster angle) in the system under study are considered. The possibility of the pseudo-Brewster angle existence and its absence for both polarisations of the incident light is shown as a function of the parameters of a rectangular nanostructure on the surface.

A new regime of secondary ion mass spectrometry (SIMS) is proposed, which allows a depth resolution of λ=1.4 nm to be achieved. The profiles of arsenic implanted into silicon, measured using this regime on a Cameca IMS-4f microprobe, were close to the true distributions. SIMS profiling of the samples of silicon implanted with 30-keV As+ ions to a total dose of (1.25–3.13)×1013 cm−2 through a 20-nm-thick thermal oxide layer showed the presence of a sharp peak of arsenic accumulated at the oxide/silicon interface, which is explained by the diffusion of arsenic to this interface as a result of annealing.

A self-forming nanostructure-a wave-ordered structure with a controllable period (20-180 nm)-results from the off-normal bombardment of amorphous silicon layers by low-energy (similar to1-10 keV) nitrogen ions. The nanostructure has been modified by reactive-ion etching in plasma to form a periodic nanomask on the surface of the channel region of a metal-oxide-semiconductor field-effect transistor (MOSFET). Implantation of arsenic ions through the nanomask followed by the technological steps completing the fabrication of the MOSFET resulted in a periodically doped channel field-effect transistor (PDCFET), which can be considered as a chain of short-channel MOSFETs with a common gate. Having worse subthreshold characteristics, PDCFETs show greater drain current and transconductance than to MOSFETs without a periodically doped channel. This improvement in device performance is attributed to the fact that the channel length is cut by the length of high-conductivity doped areas in the channel and that the voltage is distributed between the areas, depressing the scaling, rules for short-channel MOSFETs and allowing the channel to be less doped between the areas, thus keeping drift mobility high.

A wavy nanorelief is formed on the ion-bombarded surface of amorphous silicon. The nanorelief can be transferred from these films to the surface of various materials (glass, polyimide, fianite, and GaAs) by means of ion sputtering. The transferred nanorelief geometry is retained to within a depth equal to the initial relief amplitude in amorphous silicon. In the course of subsequent sputtering, evolution of the nanorelief amplitude is determined by various processes accompanying ion bombardment, rather than by the sputtering alone as characterized by the sputtering yield.

Wavy nanostructures are formed on the ion-bombarded surface of single-crystal and amorphous silicon films prepared by various methods. The period and depth of this structure have been determined as functions of the angle of incidence and the energy of nitrogen ions used for the surface sputtering. A comparative analysis of SEM images of the wavy surface nanostructures on various silicon films has been performed using a two-dimensional Fourier transform. The films of amorphous silicon obtained by electron beam deposition and magnetron sputtering techniques are closest to single-crystal silicon films with respect to the wavy surface nanostructure formation.

Wave-ordered structure (WOS) with controllable period ranging from 30 to 150 nm is self-formed under off-normal bombardment of amorphous silicon layer (a-Si) by low-energy (similar to1-10 keV) nitrogen ions. The nanostructure has been modified by anisotropic reactive-ion etching in Ar-Cl-2 plasma to form a periodic array of nanotrenches having width down to 18 nm.

The dependence of wave-ordered structure (WOS) formation during low-energy ion bombardment of silicon upon the main experimental parameters (ion type, (e.g., N2+ or O2+), ion energy, incidence angle and wafer temperature) and WOS formation dynamics have been studied. WOS in N2+/Si system are uniform, stable and their wavelengths are on the order of nanometers. The geometry and internal structure of individual waves in the N2+/Si system have been determined. We show that WOS formation on SOI using ion beams can be controlled.

The surface composition of silicon irradiated with N-2(+) ions was studied by Auger electron spectroscopy as a function of the angle of incidence and ion energy. The bombardment conditions under which ripple formation occurs were determined, and the depth at which ripples begin to form was evaluated as a function of ion energy in the range 2-10 keV for two angles of incidence. The results obtained are of practical interest in choosing conditions for SIMS depth profiling of silicon-based structures.

A new technique has solved the problem of Auger analysis of high-aspect ratio pits. The nondestructive analysis of these micron-size pits is important for the development of gigabit memory chips. Very suitable for the analysis is the coaxial scanning Auger microprobe (SAM), the electron gun of which is coaxial with the cylindrical-mirror analyzer (CMA). However, this SAM could not probe the bottom of a high-aspect ratio pit because the Auger signal is trapped in the pit. The solution to the problem was the use of an electrostatic deflector attached to the sample mount in front of the CMA. Theory and experiments proved the advantage of this technique.