Inficon Transpector CPM - Dry Etching Chemistries

5–22
Transpector CPM Operating Manual
5.3.1.5 Dry Etching Chemistries
Table 5-5 lists materials to be etched, the typical chemistries used, the chemical
species that are important, and a list of masses used to monitor each specie.
Many different chemistries exist for etching any given film. Only a few of the more
common etch processes are listed in Table 5-5. The important species listed for
each process were picked for the list on the basis of their either being reagent
gases for the listed process, known reaction product gases, potentially
troublesome impurities (e.g., H
2
O), or probable by-product gases.
Table 5-5 is not an all-inclusive list. There may be other important species, such as
highly reactive intermediates, which are not included. The list of monitored masses
for each process is a general guide.
Significant spectral overlap exists (for example, COF
2
and SiF
4
or CO, CO
2
and
N
2
), which must be considered when interpreting the data. Furthermore, many
cracking patterns for the important species are very complicated because of the
molecule’s complexity and because of multiple isotope peaks. Only a few of the
more intense or unique masses are listed.
Table 5-5 Dry etching chemistries
Etched
Material
Typical
Reagents
Important
Species
Monitored
Masses
Al (and alloys) BCl
3
/Cl
2
(+N
2
)BCl
3
Cl
2
N
2
O
2
AlCl
3
Al
2
Cl
6
HCl
H
2
O
81, 83, 116, 118, 46, 48
70, 72, 74
28, 14
32, 16
134, 97, 62, 27
266, 231, 196, 161, 134, 97, 62
36, 38
18, 17