Study of birefringence in porous silicon layers by IR Fourier spectroscopy

Anisotropy of infrared absorption in (110) porous silicon layers

“…For the films investigated α o /α e ranges from 1.3 to 2. The larger ratio is observed for the samples prepared at larger j and then characterized by stronger birefringence [3]. …”

“…PSi layers electrochemically prepared on (110)-oriented p-type Si wafers reveal strong in-plane birefringence [1][2][3]. The largest birefringence was observed for PSi layers formed from heavily doped p-type substrates [3,4] when the pores alignment is stronger [2].…”

“…The largest birefringence was observed for PSi layers formed from heavily doped p-type substrates [3,4] when the pores alignment is stronger [2]. Birefringent PSi layers demonstrate properties of an uniaxial negative crystal whose optical axis lies along the [001] in-plane crystallographic direction [3].…”

“…Birefringent PSi layers demonstrate properties of an uniaxial negative crystal whose optical axis lies along the [001] in-plane crystallographic direction [3]. The birefringence of (110) PSi was found to originate from the form anisotropy of Si nanocrystals assembling PSi [3,4]. Therefore, one can expect the optical absorption anisotropy (dichroism) in birefringent PSi [4].…”

Impedance spectroscopy of in‐plane anisotropic porous silicon films

“…The most of the studies of birefringent PS were devoted to the linear [3,4] and non-linear [5] optical properties of this material as well as to its possible applications in sensors [6] and photonic devices [7]. Recently it was established the strong anisotropy of the DC conductivity and photoconductivity in birefringent PS films [8].…”