Sequential layers of magnetic / non-magnetic material in pores:

XRD spectrum of Ni-Cu layers formed in pores of SiO₂ layer. Reflects are registered which are attributed to the FCC-phase of nickel (unit cell parameter a = 0,352 nm), FCC-phase of copper (a = 0,362 nm) and solid solution phase of  Ni_0,5Cu_0,5 compound with the unit cell parameter а = 0,357 nm (fig. 1).

Fig.1. Radiographs of the nickel-copper layers formed in the pores of the layer SiO₂.

The surface has been studied of a scanning electron microscope p-Si/SiO₂(Ni-Cu) heterostructure (fig. 2).

Fig.2. SEM image of the surface of p-Si/SiO₂(Ni-Cu) heterostructure.

This concept is possible to obtain controlled electronic material with pores in oxide on semiconductors (TEMPOS). Behavior TEMPOS-structures depends on:

• Material and thickness of the dielectric layer;
• The type semiconductor substrate;
• Sizes, shapes and spatial distribution of the tracks;
• The type and distribution of the material deposited in the pores.

Prospects of further work with Si/SiO₂/(Cu/Ni) with the goal of an amplification of the magnetoresistive effect and broadening of temperature range of its existence are concerned with a creation of sequential layers of metals in pores. For the two-layer metallic structure one can observe the MR effect (up to 40%) around room temperature (fig.3).
Application of this structure should simplify engineering of electronic circuitry  by means of the decrease of the number of peripheral elements which leads to an advantage in operation rate and higher reliability of the overall system.

Fig.3. Temperature dependence of magnetoresistance for the Si/SiO₂/(Cu/Ni) structure.

The concept allows you to create carbon nanotubes (CNTs) on nickel clusters in the pores of the layer SiO₂. On the basis of the structures of CNTs Si/SiO₂/Ni possible construction of various electrical and electronic devices.