Nanocrystalline silicon thin films prepared by low pressure planar inductively coupled plasma

Self-assembled nc-Si-QD/a-SiC thin films from planar ICP-CVD plasma without H2-dilution: a combination of wide optical gap, high conductivity and preferred 〈220〉 crystallographic orientation, uniquely appropriate for nc-Si solar cells

“…A highly crystalline nature of the pristine silicon thin lms is the characteristic of ICP-CVD operating at optimum parametric conditions. 27,29 However, interesting phenomena appear with the incorporation of carbon in the silicon network by increasing F. It has been shown in Fig. 2(a) that the nature of the Raman spectrum does not change signicantly for a systematic increase in CH 4 ow within the plasma up to F # 25 sccm.…”

“…On the contrary, the present investigation identies the predominant growth of Si nano-crystals along the h220i planes with intensity ratio I h220i /I h111i $ 2 within a highly crystalline network ($84%) at a low pressure and moderately low temperature. Such dominant crystalline growth along the thermodynamically preferred orientation might be attributed to the inductively coupled plasma with its specic characteristics mentioned above, 27,30 including its associated high density of atomic hydrogen arising from the dissociation of the SiH 4 and CH 4 . The highly energetic atomic hydrogen helps in promoting the thermodynamically preferred growth by means of chemical annealing on the lm's growing surface.…”

“…The RF eld (13.56 MHz) of 350 W has been feed through a low inductance (0.54 mH) four-antenna at spiral copper tube coil. 27,29 The RF antenna is separated from the vacuum region across the quartz window. Films are produced from 2 sccm SiH 4 used as the precursor gas and varying the ow rate of CH 4 from 0 to 35 sccm, as the source of C in the plasma, both being introduced through two separate circular gas rings placed sequentially between the substrate holder and the quartz plate.…”

“…11,23 Inductively coupled plasma CVD with very high density of plasma species, low plasma sheath potentials and excellent uniformity of the plasma parameters in the radial and axial directions can provide a high density of atomic hydrogen over the growing lm surface, which could be instrumental in strategic promotion of crystallization in the silicon network even with the C-inclusion. 6,9,13,[24][25][26][27] In this context, we report on the formation of self-assembled nanocrystalline silicon quantum dots in amorphous silicon carbide matrix (nc-Si-QD/a-SiC) with a high deposition rate by inductively coupled plasma CVD from (SiH 4 + CH 4 )-plasma without any hydrogen dilution, 28 and retaining the crystallinity at a high magnitude even aer inclusion of a signicant amount of carbon into the network. Extensive studies on the effect of increasing C incorporation on the structural, optical and electrical properties of the nc-Si-QD/a-SiC lms have been carried out.…”

Diamond-Like Carbon Thin Films from Low-Pressure and High-Density CH4 Plasma

“…In ICP CVD, a high ion-density in the plasma (~10 11 -10 12 ) is obtained via inductive discharges, enabling low pressure depositions [11].The formation of DLC films is achieved by the dissociation of the CH 4 molecules into lower hydrides CH x , which act as the precursor ions for film formation [12]. Here, DLC films with increased sp 3 /sp 2 content are formed at higher substrate temperatures and RF powers.…”