Elastic properties of porous silicon layer of hybrid SiC/Si substrates

Elastic properties of porous silicon layer of hybrid SiC/Si substrates grown by the atomic substitution method are investigated. The feature of the growth method is the formation of the macroporous silicon layer at the SiC/Si interface during growth. The elastic properties of the layer are studied using the finite element method. The biaxial modulus of the porous silicon is obtained as a function of porosity considering the different shape of the pores and presence of thin SiC boundary layer. The presence of the pores in the silicon layer adjacent to SiC results in the decrease of the elastic moduli by about 35%. However, this leads to a negligibly small change of the substrate curvature.

The Effect of Etching Time On Structural Properties of Porous Quaternary AlInGaN Thin Films

Using photo electrochemical etching technique (PEC), porous silicon (PS) layers were produced on n-type silicon (Si) wafers to generate porous silicon for n-type with an orientation of (111) The results of etching time were investigated at: (5,10,15 min). X-ray diffraction experiments revealed differences between the surface of the sample sheet and the synthesized porous silicon. The largest crystal size is (30 nm) and the lowest crystal size is (28.6 nm) The analysis of Atomic Force Microscopy (AFM) and Field Emission Scanning Electron Microscope (FESEM) were used to research the morphology of porous silicon layer. As etching time increased, AFM findings showed that root mean square (RMS) of roughness and porous silicon grain size decreased and FESEM showed a homogeneous pattern and verified the formation of uniform porous silicon.

Porous Silicon Gas Sensors: The Role of the Layer Thickness and the Silicon Conductivity

We studied the influences of the thickness of the porous silicon layer and the conductivity type on the porous silicon sensors response when exposed to ethanol vapor. The response was determined at room temperature (27 ∘C) in darkness using a horizontal aluminum electrode pattern. The results indicated that the intensity of the response can be directly or inversely proportional to the thickness of the porous layer depending on the conductivity type of the semiconductor material. The response of the porous sensors was similar to the metal oxide sensors. The results can be used to appropriately select the conductivity of semiconductor materials and the thickness of the porous layer for the target gas.