Trench-Patterned Test Wafers
Trench-patterned test wafers have etched groove patterns and are used to evaluate film coverage, gap-fill characteristics, and related properties.
Typical lead time to ship is within 1 week.
Trench patterns, hole patterns, and other structures can be formed by etching, using existing masks, newly made masks, or maskless exposure with direct-write equipment. We support 4–12-inch wafers and chips.
The trench widths listed for PT063 are mask dimensions, while those for the 6-inch product are finished dimensions after processing. Mask dimensions differ from finished dimensions.
Evaluation Applications
Conformality and step coverage can be evaluated by examining cross sections of films on the top surface, sidewalls, and bottom of trenches. Structures with different widths and depths allow comparison of film deposition in high-aspect-ratio structures.
Differences in film thickness and film quality at each location can be compared under deposition conditions such as pressure, temperature, precursor supply time, gas flow rate, purge time, and plasma conditions.
The relationship between step coverage and conditions such as pressure, temperature, and input power can be examined.
Cross sections can reveal growth from the bottom, deposition on the sidewalls, seams and voids, and the fill profile inside trenches.
Evaluation Example
PVD Cu Film Coverage
A test element group (TEG) fabricated by Philtech was used.
Discuss Trench-Patterned Test Wafers
Contact Us8-inch Trench-Patterned Test Wafers (PT063)
Trenches are formed in 200mm-diameter silicon wafers by Bosch DRIE (Si etching) using an oxide hard-mask process. Mask dimensions range from 0.2µm to 10µm, with multiple pattern groups of different widths, spacings, and trench counts arranged within 1 chip. Custom fabrication with a trench depth different from the standard specification is also available for consultation.
Basic Specifications
| Item | Details |
|---|---|
| Wafer Size | 8-inch (200mm) |
| Wafer Shape | Notch |
| Mask Name | PT063 |
| Chip Size | 18mm square |
| Mask Dimension | 0.2µm–10µm |
| Trench Length | 3.5mm |
| Process | Bosch DRIE |
| Supply Format | 8-inch wafers / 18mm-square chips |
Pattern Dimensions and Layout
Mask Dimensions, Spacing, and Trench Counts
Spacing is the edge-to-edge distance between adjacent trenches, not the center-to-center pitch. For example, “0.4µm / 1.2µm” has a center-to-center pitch of 1.6µm.
| Group | Trench Width (Mask Dimension) / Spacing | Trench Count and Layout |
|---|---|---|
| Gr5 | 0.4µm / 1.2µm, 0.5µm / 1.5µm, 0.6µm / 1.2µm, 1µm / 2µm, 2µm / 2µm | 50 trenches each |
| Gr6 | 0.2µm / 1.2µm, 0.25µm / 1.25µm, 0.3µm / 1.2µm, 0.35µm / 1.4µm, 0.4µm / 1.6µm, 0.5µm / 2µm, 0.6µm / 2.4µm, 1µm / 4µm | 20 trenches each |
| Gr7 | 0.2µm / 1.8µm, 0.25µm / 2.25µm, 0.3µm / 2.7µm, 0.35µm / 3.15µm, 0.4µm / 3.6µm, 0.5µm / 4.5µm, 0.6µm / 5.4µm, 1µm / 9µm, 2µm / 11µm, 5µm / 10µm | 10 trenches each |
| Gr8 | 0.2 / 0.25 / 0.3 / 0.35 / 0.4 / 0.5 / 0.6 / 1 / 2 / 5µm | 30µm spacing |
| Gr10 | 1µm / 4µm, 2µm / 5µm, 5µm / 7µm, 10µm / 10µm | 20 trenches, 20 trenches, 10 trenches, 5 trenches / repeated 4 times |
Unit: µm
Group Layout and Shot Map
Measured Fabrication Examples
Chips from the wafer center and edge of a fabricated product were examined by cross-sectional SEM to measure depth, top width, and middle width in regions with a trench length of 3.5mm.
Measured Values (Wafer Center and Edge)
Wafer Center
| Mask Dimension | Depth | Top Width | Middle Width |
|---|---|---|---|
| 0.2 | 20.7 | 0.49 | 0.59 |
| 0.25 | 22.0 | 0.49 | 0.66 |
| 0.3 | 22.9 | 0.49 | 0.70 |
| 0.35 | 23.9 | 0.53 | 0.75 |
| 0.4 | 24.8 | 0.67 | 0.81 |
| 0.5 | 26.3 | 0.82 | 0.92 |
| 0.6 | 27.5 | 0.90 | 1.02 |
| 1.0 | 31.6 | 1.24 | 1.41 |
| 2.0 | 38.5 | 2.01 | 2.40 |
| 5.0 | 49.1 | 4.97 | 5.33 |
| 10 | 56.5 | 9.80 | 10.21 |
Wafer Edge
| Mask Dimension | Depth | Top Width | Middle Width |
|---|---|---|---|
| 0.2 | 19.6 | 0.46 | 0.57 |
| 0.25 | 20.8 | 0.44 | 0.61 |
| 0.3 | 21.8 | 0.43 | 0.65 |
| 0.35 | 22.7 | 0.44 | 0.71 |
| 0.4 | 23.5 | 0.56 | 0.75 |
| 0.5 | 25.1 | 0.71 | 0.85 |
| 0.6 | 26.3 | 0.81 | 0.93 |
| 1.0 | 30.4 | 1.12 | 1.30 |
| 2.0 | 37.3 | 1.97 | 2.23 |
| 5.0 | 47.3 | 4.92 | 5.13 |
| 10 | 54.4 | 9.85 | 9.98 |
Unit: µm
Cross-Sectional SEM (Wafer Center and Edge)
Note: The cross-sectional SEM images were taken before removal of the oxide hard mask. Product wafers are shipped after removal of the oxide hard mask.
Low Magnification
Mask Dimension 0.2µm
Mask Dimension 0.5µm
Mask Dimension 2µm
Mask Dimension 10µm
6-inch Trench-Patterned Test Wafers
Trenches with finished dimensions of 0.5µm, 1µm, and 2µm after processing are formed in 150mm-diameter silicon wafers by non-Bosch Si etching. These trenches can be used for evaluation without the periodic sidewall scalloping produced by Bosch DRIE.
Basic Specifications
| Item | Details |
|---|---|
| Wafer Size | 6-inch (150mm) |
| Wafer Shape | Orientation flat (length 47.5 ± 2.5mm) |
| Trench Width (Finished Dimension) | 0.5µm, 1µm, 2µm |
| Process | Non-Bosch Si etching |
| Supply Format | 6-inch wafers / approximately 15mm-square chips |
| Chip Layout | 3 regions each with finished dimensions of 0.5µm, 1µm, and 2µm / 9 regions in total |
Pattern Layout
The dashed red lines show an example of dicing lines for approximately 15mm-square chips. The layout of 1 chip is described in the basic specifications.
Measured Fabrication Examples
Measured Values
| Trench Width (Finished Dimension) | Depth after Processing |
|---|---|
| 0.5µm | 5.2µm |
| 1µm | 6.5µm |
| 2µm | 7.6µm |
Cross-Sectional SEM
