Multimedia
| Images (Click the thumb to view image) | ||
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Figure
1: Two-dimensional feature with overhang. The quad-tree mesh
is constructed so the cells are concentrated around the interface.
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Figure
2: Growth rate versus view factor for growth of silicon from
silane (SiH4) and SiH2. The growth rate of the feature surface (Figure
1) is shown as a function of the view factor that the surface has
with the reactor. Where the view factor equals zero, the feature surface
has no line-of-sight view of the reactor, e.g. at a point
in the corner under the overhang in Figure 1. Conversely, at a point
where the view factor equals one, the feature surface has a line-of-sight
view at the only reactor, e.g. a point on top |
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Figure
3: Successive contours of the feature surface as silicon
is deposited from pure silane. Deposition is very uniform. As a result,
a large void is formed when the feature closes off at the top. |
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Figure
4: Deposition of silicon dioxide (SiO2) from Tetraethoxysilane
(TEOS) into a pin-joint feature. Note the relatively uniform thickness
of the deposited film. |
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Figure 5: Cryo Scanning Electron Micrograph (SEM) of SiO2 deposited from TEOS into a pin-joint; cf. the theoretical prediction in Figure 4. Note that the film under the overhang is thinner than on than on the top. i.e. it is not uniform. Note also that the bulbous features on the sides of the pin joint are a result of depositing SiO2 on top of SiO2 left over from a previous step and NOT from the non-uniform film growth. |
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Figure
6: Deposition of SiO2 from TEOS into a region between two
pin-joint features (cf. Figure 4) |
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Figure
7: CryoSEM if SiO2 film deposited between two pin-joint features
(cf. Figure 6) |
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Movies
(Click the thumb to view movies)
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180
KB |
Movie
1: Deposition of polycrystalline silicon from 100% silane
into a circular hub feature. |
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703
KB |
Movie
2: Deposition of polycrystalline silicon from a mixture of
99.9% mol silane and 0.1% mol SiH2. Note the profound difference in
uniformity from that seen in Movie 1. |