SPECIFICATIONS FOR IRON OXIDE PHOTOPLATES

1.0    GLASS PLATES

1.1    Plate Size:

GROUP A: 1.952" x 1.952" to 7.0" x 7.0" (+0 -.030")

GROUP B: 7.5" x 7.5" to 24" x 32" (+0 -.080")

1.2    Plate thickness available:

Plate Size	Glass Thickness Available
up to 4.0" x 4.0"	.060" & .090"
5.0" x 5.0"  to 6.0" x 6.0"	.060", .090", & .120"
7.0" x 7.0"	.060", .090", .120", & .190"
8.0" x 8.0" and larger	.090", .120", & .190"

1.3    Plate thickness tolerances: ±.005"

1.4    Plate flatness: .000150 inches per linear inch

1.5    Plate Quality

1.5.1    Group A (Small Plates)

Maximum number of glass seeds (bubbles) per plate: ZERO

1.5.2    Group B (Large Plates)

Maximum of glass seeds (bubbles) per 100 sq. inch area: 0.6

Seeds smaller than .002" will not be considered as defects.

Maximum size seed will be less than .020".

1.6    Glass Type - Clear, float, soda-lime silica, sheet-glass.

2.0    IRON OXIDE COATING

2.1    Thickness - two coating thicknesses are available.

3,100 angstroms ± 5% (or less) (Standard thicknes)

4,300 angstroms ± 5% (or less) (Optional thickness)

2.2    IRON OXIDE coated areas

Sheet sizes 21" x 29" or smaller - coated edge to edge.

Sheet size larger than 21" x 29" - coated to within 1" of all edges.

2.3    Usable IRON OXIDE pattern areas.

Sheet sizes 21" x 29" or smaller - usable to within ½" of all edges.

Sheet size larger than 21" x 29" - usable pattern area to within 2" of all edges.

2.4    IRON OXIDE coating defects (pinholes)

2.4.1    GROUP A: (Small Plates)

DEFECT SIZE DEFECTS PER PLATE

.001" to .003" None

> .003" to .010" None

Larger than .010" None

2.4.2    GROUP B: (Large Plates)

DEFECT SIZE DEFECTS per 100 Sq. inches

.001" to .003" 1.2

> .003" to .010" 1.2

Larger than .010" None

2.5    Inspection procedure:

IRON OXIDE coated sheets are inspected using a PIN HOLE SCANNER with the capability of detecting .001" or larger pin holes in the coating.

3.0    PHOTORESIST

3.1    Type

Standard is Shipley S 1400-30 or S 1800 (positive).

Rohm & Haas S1800 series.  (Positive working)

3.2    Method of coating:  --  Spin-coating. 

3.3    Thickness of Photoresist

Plate size	Standard	Available
up to 3.5" x 3.5"	0.5 microns	0.4 to 1.0 micron
4" x 4"	0.5 microns	0.5 to 1.5 microns
5" x 5"	0.75 microns	0.5 to 1.5 microns
6" x 6"	0.75 microns	0.75 to 1.5 microns
7" x 7"	0.75 microns	0.75 to 1.5 microns
8" x 8" to 10" x 10"	1.5 microns	1.2 to 2.4 microns
12" x 12"	1.5 microns	1.5 to 2.4 microns
14" x 14" to 15" x 15"	2.4 microns	2.4 microns
18" Octagonal	2.4 microns	2.4 microns

 

3.4    Inspection procedure

A safe light (absence of U.V.) is projected over the photoresist coated plate at an angle. Any defects will be easily observed by the inspector.

3.5    Defects

Any plate having a defect visible to the unaided eye is not shipped.

NOTE: All coating and preparation operations (IRON OXIDE and Photoresist) are

carried out under CLASS 100 conditions.

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