Solid phase epitaxy of polycrystalline silicon films: Effects of ion implantation damage

1984 ◽  
Vol 45 (8) ◽  
pp. 910-912 ◽  
Author(s):  
N. T. Quach ◽  
R. Reif
Author(s):  
Curtis Anderson ◽  
Lin Cui ◽  
Uwe Kortshagen

This paper describes the rapid formation of polycrystalline silicon films through seeding with silicon nanocrystals. The incorporation of seed crystals into amorphous silicon films helps to eliminate the crystallization incubation time observed in non-seeded amorphous silicon films. Furthermore, the formation of several tens of nanometer in diameter voids is observed when cubic silicon nanocrystals with around 30 nm in size are embedded in the amorphous films. These voids move through the amorphous film with high velocity, pulling behind them a crystallized “tail.” This mechanism leads to rapid formation of polycrystalline films.


1999 ◽  
Vol 587 ◽  
Author(s):  
Rosaria A. Puglisi ◽  
Hiroshi Tanabe ◽  
Claudine M. Chen ◽  
Harry A. Atwater ◽  
Emanuele Rimini

AbstractWe investigated the formation of large-grain polycrystalline silicon films on glass substrates for application in low-cost thin film crystalline silicon solar cells. Since use of glass substrates constrains process temperatures, our approach to form large-grain polycrystalline silicon templates is selective nucleation and solid phase epitaxy (SNSPE). In this process, selective crystallization of an initially amorphous silicon film, at lithographically predetermined sites, enables grain sizes larger than those observed via random crystallization. Selective heterogeneous nucleation centers were created on undoped, 75 nm thick, amorphous silicon films, by masked implantation of Ni islands, followed by annealing at temperatures below 600 °. At this temperature, the Ni precipitates into NiSi2 particles that catalyze the transition from the amorphous to the crystalline Si phase. Seeded crystallization begins at the metal islands and continues via lateral solid phase epitaxy (SPE), thus obtaining crystallized regions of several tens of square microns in one hour. We have studied the dependence of the crystallization rate on the Ni-implanted dose in the seed, in the 5×1015/cm3 - 1016/cm3range. The large grained polycrystalline Si films were then used as a substrate for molecular beam epitaxy (MBE) depositions of 1 [.proportional]m thick Si layers. Transmission electron microscopy (TEM) analysis showed a strong correlation between the substrate morphology and the deposited layer. The layer presented a large grain morphology, with sizes of about 4 [.proportional]m.


Sign in / Sign up

Export Citation Format

Share Document