Effect of hydrogen dilution on the structure of amorphous silicon alloys

Abstract

Articles you may be interested inEffects of microwave power on the structural and emission properties of hydrogenated amorphous silicon carbide deposited by electron cyclotron resonance chemical vapor deposition

From amorphous to microcrystalline silicon: Moving from one to the other by halogenated silicon plasma chemistry

“…Differently from SiH 4 -H 2 plasmas where H 2 %>90% is used to deposit microcrystalline films [15,17,[22][23][24][25][26], the a-Si to µc-Si transition in SiF 4 -based plasmas does not require a high H 2 dilution, as demonstrated by various papers. As an example, Shimizu and his group have reported [75] almost complete (400)-oriented µc-Si:H,F growth at gas flow ratios of SiF 4 /H 2 = 60/3 sccm at 300°C and 30 /14 sccm at 200°C, while at smaller SiF 4 /H 2 gas flow ratios such as 30/10 sccm, (220)-oriented µc-Si:H,F films were obtained using very high frequency (VHF: 100MHz).…”

“…However, all the above cited works deposited microcrystalline silicon at T>230°C. Nevertheless, H 2 , i.e., the hydrogen-dilution ratio R (H 2 /SiH 4 ), has been reported by other groups to be important for aiding the amorphous-to-microcrystalline silicon phase transitions [15,17,[22][23][24][25][26], defects [62,63] and electronic properties [64][65][66][67][68].…”

“…The life-motif of improving stability against photodegradation of a-Si:H led researchers to demonstrate recently that "protocrystalline Si", produced near the amorphous-to-microcrystalline silicon transition regime, exhibits a higher degree of ordering with increased stability under light illumination [14][15][16][17][18][19].…”

“…[15][16][17][22][23][24][25][26] or without H 2 dilution [27][28][29][30][31][32][33][34], in the course of years various halogenated Si gas precursors, e.g. SiF 4 [35][36][37][38][39][40], SiCl 4 [41][42][43], and SiH 2 Cl 2 [44,45] have also been investigated and reported.…”

Enhanced Growth Rate and Silane Utilization in Amorphous Silicon and Nanocrystalline-Silicon Solar Cell Deposition via Gas Phase Additives

“…The comparison of the behavior of these transitions as a function of single deposition parameters has been used to produce so-called deposition phase diagrams or growth evolution diagrams, which have guided the development of optimization principles in Si:H-based PV. 10,[21][22][23][24][25] For example, the structural evolution can be controlled by diluting reactive silicon carrying gases with H 2 during the deposition process. Films prepared at a low H 2 dilution remain amorphous throughout their total thickness, while those prepared at higher dilutions nucleate crystallites.…”