Visible photo- and electroluminescence from electrochemically formed nanocrystalline Si thin film

Abstract

Visible photo- (PL) and electroluminescence (EL) were observed at room temperature from nanocrystalline Si (nc-Si) thin film; nc-Si was electrochemically formed in HF aqueous solution from boron doped microcrystalline Si (μc-Si) deposited by a rf plasma chemical vapor deposition method on a glass substrate with a SnO2 transparent conductive layer. From the scanning electron microscope images, the ‘‘pore’’ structure is not found on the surface of the nc-Si thin film. PL occurs with a broadband spectrum peaking at an energy around 1.7 eV and its spectral shape resembles that of conventional porous Si made from a crystalline Si substrate. The dependence of PL intensity on crystalline volume fraction in μc-Si implies that the quantum size effects operate in the emission process in nc-Si. Visible EL emission was observed in a p-i-n heterostructured diode consisting of the nc-Si and amorphous layers with the spectral peak energy of 1.8 eV.

Blue photo- and electroluminescence of silicon dioxide layers ion-implanted with group IV elements

“…Red EL was obtained from Si-implanted SiO 2 layers [86][87][88], from sputtered or deposited Si-rich SiO 2 [89][90][91] and from nc-Si layers [92][93][94]. In [95] red PL was observed originating from a 3-nm-thick layer of natural SiO 2 .…”

Bringing Silicon to Light: Luminescence in Silicon Nanostructures

“…Visible EL has been observed, for example, from Si nanocrystals embedded in films of a-Si:H (82) and from an electrochemically-formed nanocrystalline Si thin film deposited on SnO 2 (83). In the latter case the p-i-n LED at room temperature emitted orange-red light (1.8 eV) that was readily visible to the eye.…”

“…In the latter case the p-i-n LED at room temperature emitted orange-red light (1.8 eV) that was readily visible to the eye. The light emission is ascribed variously to near surface states (84) and the quantum size effect (83). Also, infrared emission near 1.1 eV has been obtained from a room-temperature EL device comprised of Si nanocrystals embedded within a Si-rich SiO 2-x matrix (84).…”

Electrical and structural properties of nano-crystalline silicon intrinsic layers for nano-crystalline silicon solar cells prepared by very high frequency plasma chemical vapor deposition

“…The Hydrogenated nano-crystalline silicon (nc-Si:H) has attracted much attention due to its stability against lightinduced defects, high mobility and low band gap (enhanced absorption in long wavelength region) in different applications such as photovoltaics [1], thin film transistors [2], and optoelectronics [3,4]. Especially in the case of single or multijunction solar cells, nc-Si:H has shown an impressive improvement in solar cell efficiencies and in their stability [5][6][7].…”