A new polarised hot filament chemical vapor deposition process for homogeneous diamond nucleation on Si(100)

Abstract

International audienceA new hot filament chemical vapor deposition with direct current plasma assistance (DC HFCVD) chamber has been designed for an intense nucleation and subsequent growth of diamond films on Si(100).Growth process as well as the If(V) characteristics of the DC discharge are reported. Gas phase constituents activation was obtained by a stable glow discharge between two grid electrodes coupled with two sets of parallel hot filaments settled in-between and polarised at the corresponding plasma potential. The sample is negatively biased with a small 10-15 V extraction potential with respect to the cathode grid.Such design allows to create a high density of both ions and radicals that are extracted and focussed onto the surface of the sample.The current density onto the sample can be finely tuned independently of the primary plasma.A homogeneous plasma fully covering the sample surface is visualized. Consequently, a high-density nucleation (>1010 cm-2) occurs

Carbon nanostructures from Fe–C nanocomposites by activated CVD methods

“…For CF32 NP nanoparticles, a complementary spin-coating method was used for the HF DC PECVD experiment (50 droplets, ~1.5 cm 3 , 10 3 min -1 spinning velocity). The samples were introduced in the reaction chamber, endowed with anode, cath- ode, two pairs of hot wires, biased substrate facility and a heating lamp described in [20] and [21]. First, an etching treatment in hydrogen was performed, followed by the introduction of C 2 H 2 in order to grow the carbon nanostructures.…”

“…The presence of these bands may be attributed to single walled CNT (SWCNT). In case of isolated SWCNT the d diameter can be estimated by using the following relation [20]:…”

An optical emission spectroscopy study of the plasma generated in the DC HF CVD nucleation of diamond

“…Although the nucleation density has been successfully increased up to 10 8 to 10 10 cm À2 and oriented diamond films could be grown by BEN-CVD, the mechanisms responsible for this highly oriented nucleation are still unknown. In previous papers, we designed a new HFCVD chamber for an intense nucleation and subsequent growth of diamond films on Si(1 0 0) [11,12]. The activation of the gas phase for the BEN step was obtained through a polarization between electrodes separate from the substrate with a couple of two parallel filaments settled in between.…”

An Investigation of the Plasma Composition in Plasma-enhanced Hot Filament Catalytic Chemical Vapor Deposition of Carbon Nanotubes

“…The negative glow discharge above the sample can be evidenced. The catalyst preparation and the experimental procedure were already described in details in previous works [19,20]. The incoming gas of molar composition of H 2 /C 2 H 2 (80/20) with an overall flow rate 100 sccm was activated by either hot filaments or by a DC electric glow discharge.…”

“…The pressure during synthesis was maintained at 10 mbar. Two tungsten filaments of 5 mm length were placed at 5 mm above the substrate and a power of P f = 150 W was used to heat them to a temperature of T f * 2,200 K. For the direct current glow discharge, an extraction power P p * 1 W (around 300 V times 3 mA) was used [20]. In addition, an infrared lamp, settled below the substrate, heated the sample to keep the substrate temperature at 973 K, regardless the gas activation mode.…”