0.設定程序
Vision set-up
Calibration
Outline and grid definition
BGA parameters
Initial conditions
Illumination
Acceptance profile
1.Vision setup and Calibration
Step1 更換鏡頭
1.選擇鏡頭型態
| Lensset 1 | Lensset 2 | |
| Minimum ball size | 500 | 250 |
| 2D Lens | 50 mm | 85 mm |
| 2D Resolution | 49.5 micron | 27.5 micron |
| 3D Lens | 60 mm | 85 mm |
| 3D Resolution | 54 micron | 35.5 micron |
•2D鏡頭安裝的位置與QFP Inspection的位置一樣。
•3D鏡頭安裝的位置如下圖。
Step2 鏡頭校正
1.在LIM放上校正塊
＊Gull Wing Lead校正
用QFP校正塊
鏡頭：3D(85mm)+2D(50mm加濾鏡)
＊BGA校正
用BGA校正塊
鏡頭：
3D(85mm)
2D(50mm大球、85mm小球)
2.打開Illumination對話盒
3.按下表的值設定：
| Rough setting | Fine setting | Gain Settings | |
| 2D Calibration | 6 | 100 | N/A |
| 3D Calibration | 0 | 100 | 4 |
檢查看看是否符合下表規範
| Background | Foreground | |
| 2D Calibration | 60< | >220 |
| 3D Calibration | 60< | >220 |
Example of a good illumination:
1. In green display:
2. In pseudo color:
調整焦距及光圈setupilluminationcheck(調整sharpness至最高)
50mm(2D)光圈調至2
60mm(3D)光圈調至 8
85mm(2D)光圈調至5.6
85mm(3D)光圈調至 8
調整好後務必將之固定鎖緊。
5.將校正塊中心“＋”對準螢幕上的“＋”
按下F3可以叫出Cross position tool
若無法對準“＋”時，調整Camera
2D Camera Alignment
Y-translation adjustment:
Loosen the fixation screws A(2x), adjust the setscrews B(2x) and tighten the fixation
screws A (2x) again.
Y-tilt adjustment:
Loosen thefixation screws C (2x), adjustthe tilt by loosening one
setscrew D and sub-sequently tightening the other setscrew D. Tighten the fixation screws C (2x) again.
X-translation adjustment:
Loosen the fixation screws E(3x), adjust the setscrew F(1x) and tighten the fixation
screws E (3x) again.
X-tilt adjustment:
Loosen the fixation screws G (2x), adjust the tilt by loosening one setscrew H and sub-sequently tightening the other setscrew H. Tighten the fixation screws G (2x)
again.
3D Camera Alignment
Y-tilt adjustment:
Loosen the fixation screws A (2x), adjust the tilt by loosening one setscrew B and sub-sequently tightening the other setscrew B. Tighten the fixation screws A (2x)
again.
X-tilt adjustment:
Loosen the fixation screws C (2x), adjust the tilt by loosening one setscrew D and sub-sequently tightening the other setscrew D. Tighten the fixation screws C (2x)
again.
Step3 校正設定
1.按下表來設定
| Item/Ball Size | Lensset 1 | Lensset 2 |
| Number of horizontal crosses | 11 | 9 |
| Number of vertical crosses | 11 | 9 |
| Contrast | 10 | 10 |
| Inter Cross Distance | 3000 | 3000 |
| Glass lens distance | 350000 | 350000 |
| Cross dimenstion tolerance | 2 | 2 |
| Item/Ball Size | Lensset 1 | Lensset 2 |
| 2D Width of search area | 675 | 1000 |
| 2D Height of search area | 675 | 1000 |
| 3D Width of search area | 600 | 725 |
| 3D Height of search area | 825 | 1000 |
| Item/Ball Size | Lensset 1 | Lensset 2 |
| 2D Cross Dimension | 30 | 55 |
| 3D Cross Dimension X | 26 | 38 |
| 3D Cross Dimension Y | 36 | 53 |
| Number of Crosses Vertical | 設定執行XY、BGA校正時，在水平方向及垂直方向搜尋範圍能夠含蓋”+”的個數，系統容許的最小數值為3X4，為了提高校正精確度，此數值是愈大愈好，但根據上表來設定。 |
| Contrast | 影像明暗對比分化值，預設值20%，若Crosses plate有雜質或刮痕，系統可能會誤判為”+”的位置，則可加大Contrast；若在較明亮區域的”+”無法被定位時，可減小Contrast。 |
| Inter Cross Distance | 相鄰二個”+”中心的實際距離，標準的校正塊QFP Caliber=5000 BGA Caliber=3000 microns，這項設定參照上表的規定值。此數值會影響校正的正確性，與檢測系統的精確度有密不可分的關係。 |
| Glass Lens Distance | 從鏡頭到檢測平台鏡片中心的距離，即攝影機鏡頭至45度反射鏡中心點的距離加上此中心點至檢測平台距離的和，此數值僅作參考用，與系統的精確度無關。 |
| Width of Search Area Height of Search Area | 定義在校正執行時，於影像畫面的搜尋範圍，在螢幕上會以紅色的方框表示搜尋的範圍。 |
| Cross Dimension | Vision螢幕上藍色空心“+”的大小。 |
| Cross Dimension Tolerance | Vision螢幕上藍色空心”+”尺寸旁的Toleerance. |
| X center of Search Area Y | Width of Search Area上下左右的偏移量。 Height |
Step4 XY校正
1.按下Test 2D來檢查2D的XY校正結果。
2.按下Execute來檢查3D的XY校正結果。
ICOS will automatically perform and average 5 calibrations.
The Resolution should be approximatively as follows :
| Minimum | Maximum | ||
| Lensset 1 | 2D resolution | 48 | 50 |
| 3D resolution | 54.5 | 58.5 | |
| Lensset 2 | 2D resolution | 25.5 | 27.5 |
| 3D resolution | 36.5 | 40.5 |
Below you find an overview of the minimum and maximum values for the XY calibration. If the X-tilt, Y-tilt, K-ratio or residual error are out of range, the QFP set-up (not BGA set-up) should be checked :
| Minimum | Maximum | |
| Rotation | 0 | 0.50 |
| X-tilt | -0.5 | 0.5 |
| Y-tilt | -0.5 | 0.5 |
| K-Ratio | 0.995 | 1.005 |
| Residual error | 0 | 10 |
| Angle | 40 | 45 |
查 cross dimension.
查 cross dimension tolerance.
調整燈源強弱
查 number of crosses.
查search area的大小
3.將Calibration值儲存在c:\\icos\\cal路徑內(在Job內的 calibration的路徑要符合)
Stop5 Calibration check(也可不執行此項)
Calibration Check
To check the calibration, you measure a reference component several times and the system evaluates the accuracy and the repeatability of the measurements. If these evaluations are within the specifications, that is, if they are not higher than the values stored in the specification file, the system may be considered as correctly calibrated. The specification files are stored in the c:\\icos\\cer folder.
Checking the Calibration
1. Select Calibration > BGA3D > Check to display the following dialog box:
Only the items enabled in the Acceptance profile dialog box (refer to page 5-19) will be measured, the others are grayed.
2. If the model of the reference component has not been found or if you wish to check or to change the model to be used, click on the Model button. The system displays the Load Component Model dialog box showing the models stored in the c:\\icos\\cer folder (with the model currently loaded displayed in the File Name text box).
3. Click on the Align button to display the component outline and place your reference component in it. Place it in such a way that its Pin1 indication (chamfer) corresponds to the Pin1 arrow shown on the screen. The Run button becomes available.
4. Click on the Run button. The calibration count at the top right of the dialog box is incremented and the repeatability and the accuracy values are displayed only when the full test is finished.The items for which the repeatability and the accuracy are within the specifications are flagged with a green square. The items that are out of the specifications are flagged with a red square.You could get an error message “MVS: invalid measurement” if your component is not correctly aligned or if the model does not correspond.
Note: The loop count is fixed in the *.spe file.
Example of a good calibration check result:
If you click again on Run, new measurements are made and the statistics are updated. If you do not wish to take the previous measurements into account, first click on Reset, and then on Run.
There are 2 types of BGA golden units as follows :
| BGA40 | CSP40 | |
| Package size | 27 x 27 mm | 7.4 x 5.7 mm |
| Ball size | 800 micron | 350 micron |
| Model | 40BGAxxx.CMP | 40CSPxxx.CMP |
| Certificate | 40BGAxxx.CER | 40CSPxxx.CER |
| Specification | BGA45.SPE | CSP19.SPE |
| Lensset | Lensset 1 & 2 | Lensset 2 |
A third way to check if the calibration is fine, is to check if the 3D prestep windows are well aligned when the Z height is zero.
2. Outline and grid definition
The package and ball outline should be derived from the component CAD drawing as follows :
The general component data are stored in the *.cmp file. It contains the values you can set in the Component Outline dialog box (see below) and in the Ball level - BGA dialog box.
Component Outline
Select Teach > Edit > Component Outline to display the following dialog box:
Type
Type: Click on one of the four radio buttons. For BGA inspection, select the bga radio button.
Identification
Component ID: When the system is in host mode, the host may use this component number to load a component model automatically. This is done by using the “component change” request.
For an ICOS Component Inspector this ID is used to link the component model to a handler model.
The component identification must be unique.
Dimensions
Tip to tip X, Tip to tip Y, Standoff: These fields are grayed because they have no meaning for the BGA module.
Body Size X, Body Size Y: Enter the package body dimension in the X and Y directions respectively.
Ball Level
Click on Teach > Edit > Ball Level to get the Ball Level - BGA dialog box:
Ball definition
∙Width: The width of the balls.
∙Height: The height of the balls.
Reference
According to the JEDEC identification method, the balls of the component are referred to by a letter and number combination, for example A1.
∙Corner: Indicates the reference corner.
∙The Scan direction indicates the direction in which the numbers are indexed.
∙Nr. of grids: Enter the number of different grids of the component.
∙Grid: The number of the grid you want to define.
∙Position X, Position Y: Enter the coordinates of the reference point of this grid relative to the
center of the component.
∙Nr. rows in grid, Nr. cols in grid: Enter the numbers of rows and columns of this grid.
∙Row Pitch, Col Pitch: Enter the pitches of this grid (ball center to ball center), respectively in horizontal and vertical directions.
If the grid is not complete, that is, balls are missing on several positions, click on the Customize button to get the Ball Level BGA - Customize Grid graphical dialog box.
The graphical dialog box displays:
∙the name of the component and the number of enabled balls
∙the letters and numbers identification
∙the component outline
∙the size of the ball
Enabled positions are displayed as white filled circles and the disabled positions are displayed as black filled circles.
Using the left mouse button, you can enable or disable a single grid (ball) position. It is also possible to enable or disable multiple grids by drawing a box around the grid positions. The starting point is defined through the left mouse button. While moving the mouse a red outlined box appears. Releasing the left mouse button indicates the ending point. Next a pop-up menu appears containing the items Enable, Disable and Cancel. Select the wanted action.
To draw a box:
1. Click at one of its corners with the left mouse button.
2. Do not release the button and move your mouse: a blue rectangle appears. Extend this box to enclose the balls you want.
3. Release the button to tell the system the selection is done.
∙The Teach button teaches the grid configuration.
∙The Reset button enables back all grid positions.
3. BGA Parameters
Use grid alignment as standard. The size alignment is only used if the body size and grid offset have to be measured.
Use the full resolution for the alignment as a standard.
Use the following standard values for the 2D parameters
| Item/Ball Size | 750 | 500 | 350 |
| 2D contrast | 20 | 20 | 20 |
| Search tolerance | 300 | 250 | 200 |
| Number of point pairs | 32 | 32 | 32 |
| Width tolerance | 25 | 20 | 15 |
| Resolution | Full | Full | Full |
| Diameter Illum. Comp. | 95 | 95 | 95 |
| Width Shape Factor | 58 | 58 | 58 |
| Contrast Window Factor | 105 | 105 | 105 |
By increasing the number of point pairs, it is possible to improve the GR&R. Also the diameter illumination compensation has some effect on the GR&R.
The inspection time can be improved by reducing the search tolerance as well as the number of point pairs. Please note that the probability of invalids is higher if the search tolerance is decreased. Reducing the number of point pairs will affect the repeatability.
Use the following standard values for the 3D parameters
| Item/Ball Size | 750 | 500 | 350 |
| Advanced Prestep | Off | Off | Off |
| 3D prestep contrast | 30 | 30 | 30 |
| 3D measurement contr. | 10 | 10 | 10 |
| Search tolerance | 300 | 250 | 200 |
| Number of point pairs | 31 | 31 | 31 |
| Diameter tolerance | 25 | 20 | 15 |
| Segment Angle | 180 | 180 | 180 |
| Segment diameter hor. | 620 | 410 | 270 |
| Segment diameter ver. | 690 | 460 | 320 |
| Hysteresis | 0 | 0 | 0 |
The inspection time can be improved by reducing the search tolerance as well as reducing the number of point pairs. Please note that the probability of invalids is higher if the search tolerance is decreased. Reducing the number of point pairs will affect the repeatability.
The advanced prestep is necessary in the following 2 cases :
1.Interference of the pin-1 on the bottom of the package with the corner balls.
2.Too many missing corner balls (e.g. O2 or SIS device).
| Contrast | 當評估球體的品質時，此值被表示成%，相對於灰諧程度(0表示黑色－＞255表示白色) contrast of 20% 相當於灰諧值的51 可以輸入一個正數去量測球體在暗的背景下的亮度。 |
| Search Tolerance | 藍框的大小。 |
| Number of Point Pairs. | 小”+”、”-“的對數，對數愈多愈準確。 |
| Width Tolerance | Point pairs的”+”與”+”之間的距離。 |
| Diameter Illum Compensation | 若定藍框為100%，此值即為定義白框(在藍框)的大小。 |
| Width Shape Factor | 用灰諧度搜尋球體的大小，值愈小，找到的值愈大；值愈大，找到的值愈小。 |
| Contrast Window Factor | 對比window |
| 3D | |
| Number of Point Pairs. | 3D的會比2D的少一組，因為3D的影像是橢圓形。 |
| Diameter Tolerance | Point pair的”+”與”-“之間的距離。 |
| Segment Angle | Point pair的”+”與”-“分佈的範圍。 |
| Segment Diameter Horz Segment Diameter Verti | 水平及垂直方向藍色”+”偏移的量。 |
| Hysteresis | 磁滯，對Gull Wing Lead較具影響性，愈大，檢測值愈穩。 |
2D Measurement
Ball Measurement
∙Contrast: Defines when a point pair is considered good or bad. When too many point pairs are considered bad, the ball quality becomes low and you will get an invalid for that ball.
This typically happens for damaged balls, where the doughnut is incomplete at the right side. You can decrease the contrast to reduce the number of invalids. A good default value for contrast is 15%.
∙Search Tolerance: A good default is 250-300 microns (10-12 mils) for BGAs, 200 microns (8 mils) for CSPs. A lower value yields higher speed but may cause invalids if there is some variation on ball positions. If the Size module is used for alignment, the ball tolerance may need to be higher (for example 300-400 microns).
∙Number of point pairs: This value is used for the ball position measurement. The default value is 16 and gives a good result for most common cases. Grid alignment uses 16 point pairs (in full resolution) and the ball quality measurement uses point pairs.
∙Width Tolerance: Tolerance on the ball width. It determines the distance between the plus and the minus points.
∙Resolution: Use Full resolution. Half resolution yields more quickly but generates
inaccurate results.
∙Diameter Illumination Compensation: Reduces the size of the ball model to a percentage of the ball width.
∙Width Shape Factor: Width measurement uses the Profile Match algorithm and has its own graphics. The Width Shape Factor parameter only works with the profile method, not with the gradient method. When you use the normalized setting for the width measurement (select Setup > Data Format > BGA > Items) you will not see any influence.In that case the width results are normalized to the average result for all balls. If you use
Not normalized you will need to specify a Width Shape Factor parameter of about 58-60%.The actual value depends on the illumination level. Use the average width result to tune this parameter.
∙Contrast Window Factor: Defines the part of the balls used for the contrast measurement and specifies a correction on the ball perimeter.
Component Model
CyberSTEREO II/1.3/Dec-1999 5-15
3D Measurement
Alignment
The Prestep Contrast parameter influences the pre-step. A lower contrast causes the pre-step to find more candidates. The 3D pre-step will always select the outermost match positions as the corner balls, independent of the quality of the match, as long as a minimum quality is reached based on the pre-step contrast. This means that the pre-step may trigger on things like a Pin1 mark. By increasing the contrast you can avoid this, but when contrast is set too high, it may reject a less illuminated corner ball and select another one with better quality. A good default value is 30%.
Sampling Rate
Sampling rate: Specifies the sampling rate for the 3D measurement. This yields a faster inspection (only a 2D camera image is taken and only the 2D items are measured) with the 3D measurement used for process control. A sampling rate of 5 specifies that 1 in 5 components is inspected in 3D.
Optionally the MMI software can switch to 100% 3D measurement after a reject or invalid. Enable the Switch3DSampleFrequency in the pool.txt file.
Ball Measurement
∙Contrast: Defines when a point pair is considered good or bad. When too many point pairs are considered bad, the ball quality becomes low and you will get an invalid for that ball. This typically happens for damaged balls, where the doughnut is incomplete at the right side. You can decrease the contrast to reduce the number of invalids. A good default value for contrast is 15%.
∙Search Tolerance: Defines the tolerance on the ball positions. This parameter has to be larger when BGAs are warped and/or large. For CSPs it may be set to 200 microns (8 mils), for a 27 x 27 BGA to 250-300 microns (10-12 mils), for warped BGAs to 350-400 microns (14-16 mils). A larger tolerance has but a little influence on the speed.
∙Number of Point Pairs: 15 is a good value for the 3D match. Changing this parameter has not much influence on speed or accuracy (unless it becomes too low).
∙Diameter tolerance: Defines the tolerance on the ball model. A low value is advised, for example 20 microns (0.8 mils).
∙Segment Angle: Defines the part of the elliptical donut section that will be used. A good default value is 140°. In case of damaged balls the number of invalids can be reduced by increasing this angle to 180°.
∙Segment Diameter Horizontal and Vertical: Define an ellipse, which is matched to the right hand side of the balls in the 3D image. Look at the graphics in the 3D image to tune the model. Make sure the model fits the pre-step (also refer to Section BGA3D Ball Model on page 9-19). Better tuning yields better repeatability. The curvature of the ellipse should fit well around the balls, but different balls will appear somewhat differently. Tune the parameters to the average ball shape.
Usually you have to take a value that is 10-15% smaller than the ball diameter (because there is no Diameter Illumination Compensation for the 3D measurement).
The 3D pre-step uses a circular model, with a radius equal to the average of the Segment Diameter Horizontal (2x a) and Segment Diameter Vertical (2x b) parameters. This means that Segment Diameter Horizontal and Segment Diameter Vertical parameter first need to be set to make the pre-step succeed, followed by more detailed tuning for the actual ball measurement.
∙Hysteresis: Use 0 until further notice. Repeatability decreases with higher values.
Guidelines:
∙For optimal speed: Use grid alignment in full resolution, use the Size module for alignment (especially for CSPs), reduce XY tolerances (especially for CSPs), reduce the 2D ball tolerance, increase the contrast, reduce Number of point pairs parameter for 2D. 3D parameters (for example ball tolerance, Z tolerance) have a rather limited influence on overall speed. For CSPs the Z tolerance can have more influence.
∙For optimal repeatability: Small width/radius tolerances (20-30 microns), reduce the Diameter Illumination Compensation parameter to bring plus points well in the doughnut and minus points just outside, tune 3D X- and Y-diameter, increase illumination. When you see a coplanarity repeatability problem, first check the X and Y offset results. Bad repeatability in offset directly translates into bad coplanarity and repeatability.
2D
增加number of point pairs 至32, 會增加GR&R的穩定度.
Diameter illumination compensation 對GR&R也會有影響.
減少檢測的時間可減小 Search tolerance 和 Number of point pairs的值.
減小 Search tolerance 的值可能會有Invalid的情況產生.
3D
˙增加Number of point pairs至30 可增加GR&R的重複性
˙修改horizontal 和 vertical segment diameter 也會影響 GR&R.
∙減少檢測的時間可減小 Search tolerance 和 Number of point pairs的值.
∙減小 Search tolerance 的值可能會有Invalid的情況產生.
3.校正BGA在LIM的高度
You can use the special height tool MC2279 to make sure the handler places the components at the correct height. Place the height tool in the inspection module, attach a component to the nozzle of the handler and lower it on the height tool until the balls touch the surface. This defines a good Z-position value for the handler.
Step1.Use the black height tool for setting up the “Down at LIM”z1 level.
Step2.Use the flat idle station and switch on the “no clamping at idle station”option
Step3.If handler ver.P5.3,it is also possible to switch off the z stroke at the LIM.
4. Initial conditions
Use a standard X and Y tolerance of 1000 micron, and a Z tolerance of 500 micron. The rotation tolerance can be standard 2 degrees.
For large BGAs or on a 8450, a tolerance of 750 micron could be necessary.
Most invalids measurements are due to bad initial conditions settings. Following items can be checked :
X and Y position in case of BGA-2D invalid.
Z position in case of BGA-3D invalid.
Increasing the X and Y tolerances as well as the rotation tolerance will help for reducing the 2D invalids, but it will also slow down the machine.
Increasing the Z tolerances will help for reducing the 3D invalids, but it will also slow down the machine.
∙將X and Y的 tolerance 設為 1000, Z 的tolerance 設為 500,rotation tolerance 設為 3 degrees.
∙很多的Invalid是由於initial condition的設定有問題,請查察以下的設定 :
X 和 Y 位置設的不恰當 會造成 BGA-2D的 invalid.
Z 位置設的不恰當 會造成 BGA-3D 的invalid.
增加tolerances的值 將會有幫助, 但會減緩機器的速度
5. Illumination
For the 2D illumination, the width of the donut should be equal or a bit larger than the width of the centre.
For the 3D illumination, the width of the right donut segment should be equal or a bit larger than the width of the centre, and double the width of the left donut segment.
An illumination contrast check is available as follows :
The rough settings should be fixed as follows :
| Rough setting | Gain settings | |
| 2D Illumination | -3 dB | N/A |
| 3D Illumination | -3 dB | 4 |
The fine settings should be tuned with the illumination contrast check until the following values are reached (GV Range = GV Maximum – GV Minimum) :
| GV Average | Maximum GV Range | |
| 2D Illumination | 215 GV | 50 GV |
| 3D Illumination | 190 GV | 70 GV |
There is quite some variance on the value for the fine settings. Especially for the 2D illumination, the fine settings will vary quite a bit depending on the ball size. The fine settings for the 3D illumination is more stable.
If the 2D illumination is too low, the system will overkill on CT and QU, and vice versa. At this moment there is no set-up that garantees 0% underkill without having a serious overkill problem.
If the 3D illumination is too high, the CO will be too high. If the 3D illumination is too low, there will be many 3D invalids.
6. Acceptance profile
