Light-emitting porous silicon: materials science, properties, and device applications

Porous Si(111) and Si(100) as an intermediate buffer layer for nanocrystalline InN films

“…In general, the InN Reststrahlen region lies between 400 cm −1 and 600 cm −1 whereas the Si is inactive in IR region. For InN thin films, the features corresponding to the TO [E 1 (TO)] phonon modes of the InN are clearly seen at 472 cm −1 and 470 cm −1 for porous Si(1 1 1) and Si(1 0 0) substrate, respectively, which is comparable to the reported values for wurtzite InN [17]. However, we did not observe the feature (dip) due to the LO [A 1 (LO)] phonon mode of the InN (located at around 580-590 cm −1 ).…”

“…When porosity is formed, these materials exhibit various special optical features, for instances, the shift of bandgap [14], luminescence intensity enhancement [15], as well as photoresponse improvement [16,17]. Among porous semiconductors, porous silicon (PSi) is a material creating great scientific and technological interest because of its ample range of application; it has recently been used as an active element and as an anti-reflective film in solar cells.…”

Mechanical strength of porous silicon and its possible applications

“…Unusual electrical and optical properties have been discovered due to its nanosized structure. Much work has been done on photoluminescence and electroluminescence properties [3]. Meanwhile still there are "forgotten" applications of PS exploiting it from "non-semiconductor" point of view.…”

Porous GaN prepared by UV assisted electrochemical etching

“…The unique physical properties of the porous layer such as, high surface area, shift of bandgap and efficient luminescence are among the special features which show promise in some of the sensing applications [1,2]. Among porous semiconductors, porous silicon receives enormous attention and has been investigated most intensively; however the instability of physical properties has prevented it from large scale application [3]. This leads to the development of other porous semiconductors, for instance, the conventional III-V compounds such as GaAs [4][5][6][7], GaP [8][9][10] and InP [11,12]; and the wide bandgap materials such as SiC [13][14][15] and GaN [16][17][18][19][20][21][22][23].…”