ONTRAK II CE Series Installation Manual page 152

7.2.1 Starting Material
7.2.1.1 The wafer surface should be hydrophilic. A hydrophobic wafer causes
water to bead on its surface. The thickness and thickness uniformity of
oxide layers can influence particle detection sensitivities of the measure-
ment system. Also, organic contamination on the wafer surface can effect
surface condition. Generally, a SC1 cleaning (H
solution in a 5:1:1 or 7:2:1 ratio) will remove organic contaminants and
result in a "fresh" hydrophilic surface.
7.2.1.2 Only high purity NH
purity and low particulate levels are required for all chemicals used in the
scrubbing process.
7.2.2 Contamination in starting chemicals and/or the NH
be identified by using a 3 gallon pressurized canister as an alternative delivery
source and/or an alternate source of NH
7.2.3 DIW particulate and/or bacteria problems may be determined by processing
wafers through the scrubber with the brushes "up" in both brush stations and
running a rinse, dry cycle in the Spin Station. If there are no DIW problems, this
test should result in very few adders for clean wafers (< 50 particles/wafer)
and some reduction in particle level for dirtier wafers (> 200 particles/wafer).
7.2.4 Individual Process Stations
7.2.4.1 Input Station
7.2.4.1.1 Verify that all Input Station DI water sprays are functioning
7.2.4.2 Brush Station #1
7.2.4.2.1 NH
7.2.4.2.2 DI water delivery system. If a point of use (POU) filter is used,
7.2.4.2.3 Brushes.
7.2.4.3 Brush Station #2 (See Section 6.5.)
7.2.4.3.1 NH
7.2.4.3.2 DI water delivery system. (See Section 7.2.4.2.2.)
7.2.4.3.3 Brushes (See Section 6.5.)
7.2.4.4 Spin Station
pro-4
OH such as Gigabit grade should be used. High
4
properly and that all wafers are fully covered with H
OH delivery system. Verify that the 0.1 micron point of use
4
(POU) filter is properly installed, properly wetted, and not
clogged.
verify that the POU filter is properly installed, not overdue to be
changed, not become contaminated, properly wetted (if required
- Teflon), and not clogged.
OH delivery system. (See Section 7.2.4.2.1.)
4
DSS-200 Series II CE Installation Rev. C
P/N 20-0200-018-004, 20-0200-017-004 (CR)
O + H
2 2
OH delivery system can
4
OH.
4
O + NH OH
2 4
O.
2
2/11/99