TEMScripts Auto Image Measurement (Pattern) Manual. TEMScripts LLC. Last updated: 12/5/2016

Transcription

1 TEMScripts Auto Image Measurement (Pattern) Manual TEMScripts LLC. Last updated: 2/5/206

2 Close Digital Micrograph TS EasyMetro Installation Copy following files to \\Gatan\DigitalMicrograph\PlugIns (normally under C:\Program Files (x86)\ or C:\Program Files\) TEMScriptLicense.dll TS EasyMetro.gtk HREMMouse.bmp (freeware from HREMReserch Inc.) HREMMouse.gtk (freeware from HREMReserch Inc.) Restart Digital Micrograph Select TS Image Analysis under DM menu Windows Floating Windows TS Image Analysis palette should be visible. Select Pattern to initiate TS EasyMetro

3 Open images This is to open all images for measurements. Click Open Images button () near the top-right corner. A dialog will be popped up (2), which allows you to specify the directory containing all the images. After the path is chosen, a file name filter (3) is available so that you can select some images to process. If the filter is empty, all images under the directory will be chosen. 2 3

4 Load Front Image This is to select the font image for training and auto-measurement. This image will be used as the recipe for batch process. Click one image which can be used as a recipe. After the click, the image should stay front. Click Load Front Image () near the top-left corner of the dialog. If a sampleid has been assigned to this image, it will be shown up near the right side of the button. Following image training and measurements will be processed upon this image once the Load Front Image has been pressed. We can always select another image from here.

5 Set up CDs This is to set up the CDs for the measurements. The recipe image will pass down all the CDs to all other images during following Run Batch process, so make sure that you have a complete list of measured CDs. Input CD in the dialog (). Click Add CD (2). The input CD will be added in the CD list. 2

6 Step I: Recipe Image Training

7 . Auto Edge Detect Both the image measurement and feature identification through the pattern recognition are based on the edge detection. Click Auto Edge Detector and wait for seconds. The recipe image with edges overlapped on is shown up. The red line indicates major edge, while green line shows weak edge. The measurements and pattern recognition only use major edges. The weak edges are shown as a reference to adjust the threshold.

8 .2 Edge Tuning The purpose of edge tuning is to maximize the edge signals and minimize the noise. Strong edge: any pixel above the strong edge threshold will be marked as major edge marked as red in color. Weak edge: any pixel between weak edge and strong edge thresholds will be marked as weak edge (green in color). Pixels below weak edges will be considered as the background. Pixel ratio and difference: which provide additional approaches to enhance the signal/noise ratio. When the edge detection is acceptable, click ON/OFF Edge (2) to hide the edge. 2

9 .3 Reference line (orientation) The reference line indicates the reference orientation. Most semiconductor devices are fabricated on Si substrate, and the reference line is parallel to the Si surface. This is important for CD measurements, and also for program to handle images with different rotation angles. Click ON/OFF Reference Line (). The program will shows a reference line on the image. You can also manually draw a ROI line, and click Manually Set Reference Line (2) to set the orientation. Click ON/OFF Reference Line () again to hide or show this reference line. The reference orientation has a resolution about 0. degree. 2

10 .4 Number of Patterns The feature is identified through pattern recognition. The number of patterns need to be specified. In the image below, for example, we have four patterns. It is expected that different images have similar number of patterns

11 .5 Train ROI ROI training is to specify a region containing a reference feature with auto measurements. This reference feature will be used during pattern recognition to identify other features in the same image and in batch images. Draw a rectangular ROI to select the reference feature, and then press Set Train ROI (). Click ON/OFF Train ROI (2) to show or hide the ROI again. 2

12 Step II: Define Recipe Measurement

13 2. General procedures Generally there are three steps: () select a CD; (2) select a suitable measurement type; (3) follow the instruction to complete the measurement. There are five different measurement types, namely, () Auto CD; (2) Line CD; (3) Trench and recess; (4) Angle measurement; (5) Multiple CDs. Specific examples will be given to demonstrate how to conduct measurement for each type. 2

14 2.2. Auto CD This function is to measure the CD of very thin layers, maybe with irregular orientation. The program will determine the orientation and edges in the selected region. Make sure there is no other strong edges in the area.. Select a CD in the list. In this case, Nitride thickness. 2. Select Auto CD (rectangular ROI) 3. Select rectangular ROI from DM toolbar. 4. Draw a rectangular ROI surrounding Nitride liner. 5. The Nitride thickness was measured and marked in the image automatically. 6. Click END M when it is done

15 2.2.2 Line CD 3 This function is to measure the CD through a line. It might be one of the most popular measurement approach.. Select a CD in the list. In this case, W CD. 2. Select Line CD Select line orientation: which can be parallel or perpendicular to the reference line, or any direction if Set by user is chosen. Gradient means new edge with maximum gradient. B/E will connect to other line end either at the beginning or end side. Both will connect to other line ends at both sides. 3. Select a line ROI from DM toolbar. 4. Draw a line ROI near the interested area 5. The thickness will be measured and marked in the image automatically. 6. Click END M2 when it is done. 2

16 2.2.2 Line CD 3 Example below shows the measurement of W CD. When Parallel to reference line is chosen, the line is fixed to this direction. Two windows are visible when a line is drawing. Make sure that the edge is within the window at both ends. The edges will be identified automatically when the mouse is released, and the line is shown on the image. 2

17 2.2.2 Line CD 3 Example below shows the measurement of W thickness with orientation perpendicular to reference line. Two windows are shown when a line is drawing. Make sure that the edge is within the window at both ends. The edges will be identified automatically when the mouse is released, and the line is shown on the image. 2

18 2.2.3 Trench and recess 3 This function is to measure the recess or depth of a trench. There are mainly two steps for this type of measurement. First we need to define a reference line, and then perform the measurement.. Select a CD in the list. In this case, Nitride recess. 2. Select Trench and recess 3. Select a line ROI from DM toolbar. 4. Draw a line to set up the reference. Two windows will be shown when a line is drawing. Again make sure that the reference edge is within the window. 5. The reference line will be shown when the mouse is released. The line end points have been adjusted to the strong edge in the windows

19 2.2.3 Trench and recess 6 6. Select a rectangular ROI from DM toolbar. 7. Draw a rectangular ROI containing the end point of recess. 8. Release the mouse, and the recess measurement will be shown automatically in the image. Again the recess point was determined automatically based on the maximum gradient. 9. Click END M3 when the measurement is done

20 2.2.4 Angle measurement This angle measurement requires the specification of 4 points, 2 at each sides of the angle.. Select a CD in the list (). In this case, Side wall angle. 2. Select Angle measurement setup: two points on each side (4) and enable the DM Mouse (2). 3. Click on the image to set up four points, two on each side of the measured angle (3). 4. Select Measurement. The angle will be measured and shown up in the image in degree. The angel edges have been adjusted to align to the strong edges before the measurement (5). 5. Turn off the Mouse mode when it is done (6)

21 2.2.5 Multiple CDs 3 This function can be very helpful when multiple CDs need to be measured stimulatingly along the same direction.. Press Multiple CDs (), and select line orientation (i.e., parallel, perpendicular to the reference line, or any orientation). A message box (2) will be popped out to request the number of CD. Click OK when it is done. 2. Select a line ROI from DM toolbar (3). 3. Draw a ROI line, make sure that the starting and ending edges are within the windows (4)

22 2.2.5 Multiple CDs 4. After the ROI line is drawn, an edge profile is shown up (5). As exemplified below, the ROI line was divided into 5 sections, which is the total CD number specified. If some adjustment is necessary, select a ROI (e.g.,, 2, 3, 4, or 5) in the edge profile and perform the adjustments. At the same time, you can notice that ROI line on the image is changing stimulatingly along with the edge profile adjustment. 5

23 2.2.5 Multiple CDs 5. When the ROI line is okay, next step is to assign CD Select CD assign (6). The image shows the first CD (7). Select the CD from the list. In this case Nitride liner left. Click CD assign (6) again. The image will show the second CD (8). Select the CD from the list accordingly. In this example, Ox spacer left. Repeat the process above until all the CDs have been assigned. The edge profile will disappear when it is done

24 2.2.5 Multiple CDs 6. Below shows the image after all the CDs have been assigned (9)

25 2.2.5 Multiple CDs 3 7. This process can be simply duplicated. Click Duplicate (0). Select line ROI (3) Draw a ROI line () Release the mouse. All the edges will be identified and the measurement is completed (2). 0 2

26 Step III: Run Batch

27 3 General Procedures When the measurements for the recipe feature have been completed, it is time to run the batch process. Make sure all the images are open in Digital Micrograph.. Press Save Current Image as Recipe (), which will save all the parameters, set up and measurement. 2. Press Select Current Image as Recipe (2), which officially specify the current image as the recipe image. 3. Press Run Batch (3). All the open images in DM will be process and measured. A message box showing batch completed will be popped out when it is done. Depending upon the number of images, the time can be different. Generally each image may take about 20~30 seconds, again depending upon the computer configurations. 2 3

28 3 General Procedures 4. A Copy Batch function is provided to deal with cases where the feature is not suitable for pattern recognition. This function simply copies all the information (including CD list, measurements) from the recipe image to all open images. Generally it requires manually adjustment after the Copy Batch. Most semiconductor devices are suitable for pattern recognition and Batch run, but material structure images, such as the grain boundaries, may have to be handled manually through the Copy Batch. 4

29 Step IV: Post Processing

30 4. Turn ON/OFF line ends The line ends are good to visualize the CD, but if you would like to manually adjust the CD, it is much convenient to turn it off. OFF ON

31 4.2 Quality check of the measurement It is highly recommended to have a quality check after the auto measurement. Some factors may induce falsepositive. When identified, it is convenient to have a manual adjustment.

32 4.3 Turn ON/OFF CD labels If too many measurements are performed on the same image, it may look busy with all the CD labels ON. Otherwise, it is always a good practice to turn ON the CD labels.

33 4.4 Save Images When this button is pressed, all images will be saved automatically. It is worth noting that all images should be saved before we perform the Data Collection. 4.5 Data Collection Click Data Collection (2). A dialog (3) will be popped out requesting the directory. Select one, and click Okay. The measurement results will be saved under the same folder in a format of TSV text file, which can be conveniently processed through Excel or JMP. 3 2