This document is divided into the following sections.

Transcription

1 Chip Algorithm Setup S1 Purpose The purpose of this document is to assist trained 5DX programmers with setting up the Chip algorithms. In this document This document is divided into the following sections. Topic See Page Initial Chip setup 1 SPC setup with graphics 2 Threshold setup without graphics 3 Threshold setup for clear chips (optional) 5 Final Chip setup 7 Chip setup process flow 8 Initial Chip setup Follow these steps to initially set up the Chip algorithm. 1 Set the following threshold values for all subtypes. LOCATOR SEARCH_DIST 0.50 SEARCH_DIST_ACROSS 0.50 SPC MIN_BODY_THICK_PCT 50 SHORT MIN_THICK_MILS_SIDE 4 MIN_WIDTH_MILS 5 USE_LEARNED_JOINT 1 IPD_REDUC 0.9 EXCLUDE_REGIONS 48 INSUFFICIENT OPAQUE_RJT_PCT 40 CLEAR_RJT_PCT 40 MISALIGNMENT OPAQUE_LOC_ALONG 60 OPAQUE_LOC_ACROSS 60 MAX_OPAQUE_ROT 20 OPEN MAX_SOLDER_AREA 0 MIN_FILLET_SLOPE 50 MAX_GAP_EDGE 10 Note: These thresholds have been set based on the assumption that Chip is being used to test opaque chips. If there are chips that are clear in the x-ray image, these chips will initially fail. The Threshold setup for clear chips section provides steps for setting up clear chips. Ver 1.2 Page 1 of 8

2 Initial Chip setup (continued) 2 Set up the AlgSlice NDF file. Comment out Chip Short during initial setup. This will reduce false-calls during initial testing. Comment out Chip Excess to permanently exclude them from the test. Joints that have excess solder will be caught by Short. Include Chip Locator, SPC, Insufficient, Open and Misalignment in the test. SPC setup with graphics With SPC Graphics turned on, test each subtype and complete the following steps. 1 Verify the CAD body size. a. Verify that the size of the cyan box matches the body length. The body length is defined as the distance between the inside edges of the fillets. See the Agilent 5DX Approved Programming Practices CheckCAD for information on how to adjust the length. b. Verify that the width of the inner blue box matches the body width. See the Agilent 5DX Approved Programming Practices CheckCAD for information on how to adjust the length. Ver 1.2 Page 2 of 8

3 SPC setup with graphics (continued) 2 Verify the position of the background profile boxes. The background profile boxes should not overlap any adjacent objects. If they do overlap, adjust the BKGND_PROFILE_SHIFT threshold. Larger values move the profile away from the component. 3 Verify the fillet region. Verify that the green and blue boxes are approximately the size of the solder fillet. If they are not, adjust the PAD_REGION_LENGTH threshold. Larger values increase the size of the fillet region. Threshold setup without graphics With SPC Graphics turned off, test each subtype and complete the following steps. 1 Set the nominals. a. Test the Chip Joint Type, and create a Summary Data Sheet of the SPC measurements. b. Select Update Thresholds to write the nominal solder thickness values for all subtypes. Ver 1.2 Page 3 of 8

4 Threshold setup without graphics (continued) 2 Set the Open thresholds. a. Create a Raw Data Sheet of the Open Diagnostic measurements using an OPAQUE, OPEN DIAG Chip filter. Note: The filter should contain (1) Body Length. b. Chart the Body Length for each subtype. Ignoring all extreme values, record lowest value and subtract 10%. For example: 87 (10%) = (87-9 ) = 78 Note: Extreme values may represent defective solder joints or out of focus images. These can be confirmed by running a test with SPC graphics enabled. c. Set the MIN_BODY_LENGTH threshold to this value. 3 Reduce false calls. a. Retest the Chip joint type. b. Use Review Defects to examine all calls. c. Loosen the thresholds to reduce false calls. Note: If any of the defects indicate the present of a clear chip, complete the following Threshold setup for clear chips section. The default thresholds for Open are set so that if any chip is clear, it will fail. If there are no clear chips on the panel, skip to Final Chip setup on page 7. Ver 1.2 Page 4 of 8

5 Threshold setup for clear chips (optional) With SPC Graphics turned on, test each subtype that contains clear chips and complete the following steps. 1 Verify the contour. The contour should fit tightly around the fillet of each joint. If the contour is too loose, raise the CONTOUR_FRAC threshold. If it is difficult to adjust the contour because the chip is fairly opaque, it may be better to test as an opaque. Lower the MIN_BODY_THICK_PCT threshold to test it as an opaque chip. Ver 1.2 Page 5 of 8

6 Threshold setup for clear chips (optional) (continued) 2 Set the Open thresholds for clear chips. a. Turn off SPC graphics and retest all subtypes that have clear chips. b. Create a Raw Data Sheet of the Open Diagnostic measurements using a CLEAR, OPEN DIAG Chip filter. Note: The filter should contain (1) Pad Area and (2) Pad Slope. c. d. Chart the Pad Area for each subtype. Ignoring all extreme values, identify highest value for an acceptable joint and add 10%. e. Set the MAX_SOLDER_AREA threshold to this value. f. Chart the Pad Slope for each subtype. Ignoring all extreme values, record lowest value for an acceptable joint and subtract 10%. g. Set the MIN_FILLET_SLOPE threshold to this value. Note: Use of an "opens" panel is strongly recommended for setting open thresholds for clear chips. Complete the following steps if you have an "opens" panel available. a. Chart the Pad Area and Pad Slope using tests of both the loaded and unloaded panels, sorted by run. There should be a clear gap between measurements taken on the loaded panel (assuming all joints are good) and unloaded panel. b. Choose a value for MAX_SOLDER_AREA below the values for the unloaded panel and above the values for good joints. c. Choose a value for MIN_FILLET_SLOPE above the values for the unloaded panel and below those for good joints. d. If there is not complete separation for slope, you could change the algorithm to look at the inner pad slope rather than outer (set FILLET_EDGE_LOC to 1) and test again. Note: Another cause of an incomplete separation between good and open joints when using an "opens" panel is poor focus. Check for proper Z-height. Ver 1.2 Page 6 of 8

7 Threshold setup for clear chips (optional) (continued) 3 Reduce false calls. a. Set non-populated chips in the Component NDF to true to test the effectiveness of the Open thresholds. b. Retest the subtype. c. Use Review Defects to examine all calls. d. Loosen the thresholds to reduce false calls. e. Verify that you can catch both pins of the missing chip. Final Chip setup Use the following steps to complete the Chip setup. 1 Set up Short. a. Remove the comment from Chip Short in the AlgSlice NDF file. b. Turn on joint learning for Chip Short. c. Test the Chip joint type on one or more panels that do not have shorts. d. Turn off joint learning for Short. e. Retest the joint type and check for false calls. Note: To save setup time, joint learning for Short can be postponed until all algorithm families have been adjusted up to that point. Joint learning can then be done for the entire application. Ver 1.2 Page 7 of 8

8 Chip setup process flow Ver 1.2 Page 8 of 8