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GBIC >> MCM >> Online MCM Design
Design your own MCM by editing the information below, then press "View 3D Image" to see your design!
Full Instructions    MCM Cross-section    Design Features   
Part Data    Display Options    STL
Parts List:
Package Design:
Total I/O
View MCM Design

Size   Place   4up  Shaded  Rotate  White 

Constrain  I/O  Lid  STL   Aspect

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Full Instructions

The design results of this page are approximate. Review your specific MCM needs with the professional MCM design center of your choice.

To design an MCM using this site, you must select a list of parts for your MCM and enter some very basic package design requirements. With that information this site can generate some very detailed MCM design information - including size, weight, power and thermal analysis.

In addition to the basic parts list/package design information, there are approximately 160 additional design parameters or materials properties which you can modify to adjust the MCM design. The details of those adjustments are provided further down on this page.

Parts List:

  • Edit the part descriptions as required. Up to 8 part types are supported.
  • Using the drop-down lists, select the number of components to be used in the MCM.

Package Design:

  • Enter the number of external I/O your package requires
  • Select the type of package interface to be used in the design (leads, perimeter pads, BGA pads)
  • Select the type of interconnect to be used in the package (drop-in or integrated)

View MCM Design:

  • Press the "View 3D Image" button to view the 3D image of the MCM using the Parts List and Package Features you've chosen. The server should respond within 2-5 seconds with the results.
  • Rotate and resize the MCM 3D graphic by dragging the image with the left mouse. The buttons on the 3D image windows allow you to rotate, resize, and re-position the 3D image. You can also alternate the display between wireframe and shaded format.
  • Read the additional notes provided beside and below the 3D image. Size, weight, power, and parts list information is displayed at the side of the image. Additional information, including weight analysis and thermal analysis is provided below the image.
  • To make changes to your inputs, simply press the browser "back" button, edit the page, and again press the "View 3D Image" button.
  • To maintain a copy of a quote, press the "Save" button. This puts all of the data from the page into a cookie on your PC. You can retrieve the data at any time by pressing the "Restore" button. Only a single cookie is supported at this time.
  • All entries may be returned to their default values by pressing the "Reset" button. The "Reset" button does not clear the Saved data - it resets only the displayed values.
  • All of the designs generated by this page are deleted from the server after 24 hours. You can use the Save feature to save a specific design (only one Saved design is supported), or you can use the Save As feature of your browser to save any number of designs.

Miscellaneous Options

Along the bottom of the input screen is a list of options which will affect the design of the MCM or the way in which the 3D image is displayed.
  • Size
    The window containing the 3D image is square. You may set its width using this drop-down list. Size is given in pixels.
  • Place
    Three parts placement algorithms are available. The standard placement algorithm places parts in order of their width. The random algorithm selects parts randomly before placement. The optimized algorithm attempts to intermingle parts, alternating between large and small parts. This simulates the extensive use of passive components (resistors and capacitors) between semiconductor components.
  • 4up
    Normally a single 3D image of the MCM is displayed. Select this option to display four 3D images of the MCM design (in a 2x2 matrix). Each image can be separately controlled.
  • Shaded
    The default is to display the 3D image as shaded (solid, within lighting effects). Unchecking this option will change the image to a wireframe display.
  • Rotate
    The 3D image can be set to rotate continuously with this selection. By default, the image does not automatically rotate.
  • White
    The default image background is black. Selecting this option will change the background image to white.
  • Constrain
    An MCM body size is determined by the larger of the area needed for components or the area needed for the package I/O. By default, the MCM is sized according to the area needed to place the components. Uncheck this option to allow the package to grow to the size defined by the larger of the component or I/O requirements. The MCM graphic is accompanied by a message showing which condition was used to generate the graphic image.
  • I/O
    By default, the package I/O (leads, pads, solder balls) are displayed. Unselected this option to inhibit the display of the I/O. This will not affect the weight calculations. Displaying a large number of solder balls (several hundred) can significantly slow the time initially display the 3D image.
  • Lid
    The lid of the MCM is not normally shown in the 3D image. This allows the internal features of the MCM to be shown. Select this option to have the lid displayed. The lid may also be positioned above the body of the MCM to give an exploded view (see details further down this page).
  • STL
    Selection this option generates a file which can be used to manufacture a mechanical sample of the MCM using stereolithography. This is a very useful option! If you haven't been exposed to stereolithography, read my short STL introduction
  • Aspect
    The placement algorithms typically provide a design which has an aspect ratio of about one. Increasing/decreasing the Aspect value will have a corresponding effect on the aspect ratio of the MCM package dimensions. The effect is not linear, so some experimentation with the setting may be necessary to achieve the results you want.

The rest of this page contains all of additional design and material assumptions that are used to generate the MCM graphics. You may make changes to these values as required by your specific MCM design requirements.

General Comments

  • Integrated Package
    As you can see in the graphics below, an integrated package form factor is supported by this site. Normally this would mean that no substrate is used and that the interconnect is built into the package base. However, this is not always the case. For example, sometimes a thin film interconnect is fabricated on the top of a ceramic package base. To support this case,the interconnect is allowed to have a non-zero thickness value when the "integrated" form factor is used. If the MCM design is truly integrated (i.e., the interconnect fabricated within the package), simply set the interconnect thickness to zero so that the generated 3D graphic will be accurate.
  • Graphics generation time
    Be aware that BGA solder joints for large I/O counts can significantly add to the time required for the server to return a solution. For large solder joint counts the http connection may time out before receiving the solution.
  • Revision levels
    • Ver. 7.0 Placement options, additional sizing options, uers manual update
    • Ver. 6.0 Binary STL export
    • Ver. 5.0 ASCII STL export (text), optional 4-up graphics display
    • Ver. 4.0 Thermal analysis, exploded view, separation of interconnect from substrate, option to constrain package by parts or I/O, 50% reduction in speed of graphics generation (hidden face elimination)
    • Ver. 3.0 User defined part names, weight analysis, BGA package with solder ball display, multiple display resolutions (550 to 1000 pixels)
    • Ver. 2.0 Color display with user defined colors, integrated package construction, online instructions, option to save design (cookie)
    • Ver. 1.0 Initial release, 3D Graphics, fixed parts list, size/power analysis, leaded drop-in package

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MCM Cross-section

The first drawing below shows a cross-section of an MCM, giving the location of the primary MCM features (drop-in construction style). The remaining images show various construction options which this Online MCM Design Center supports.


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MCM Design Features

Typical MCM feature sizes are provided in the following table. Not all features apply to all MCM construction types. All dimensions are in inches.
Solder Balls
Perimeter Pads
  Material Kovar Copper
  Wirebond pitch
  Wirebond keepout
  Assembly keepout  
  Bond pad keepout
  Material Thick film Thin film
Laminate  RDL
  Substrate thickness
  Substrate material Silicon Ceramic
Aluminum nitride 
  Dropin keepout
  Wirebond ledge width   
  Wirebond ledge height   
  Seal ring width
  Seal ring keepout
  Lead ledge width
  Corner keepout
  Display wires
  Seal ring material Kovar Nickel
Aluminum Plastic
  Package material Ceramic Kovar
Laminate  RDL
  Material Kovar Aluminum
Thermal model
  Part attach: Epoxy Epoxy (cond) Solder
  Part attach thickness
  Substrate attach: Epoxy Epoxy (cond) Solder
  Substrate attach thickness
  Package attach: Epoxy Epoxy (cond) Solder
  Package attach thickness

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Part Data

The following list contains typical components used in the design/manufacture of MCMs. Parameters given are typical and may vary according to the customer's design.

Components Power 
 I/O Thermal

Description Thermal
  Description Thermal
Epoxy Epoxy (conductive)
Thick Film Thin Film
Cofired Ceramic Laminate
RDL Encapsulation
Thermal spray Kovar
Aluminum Aluminum nitride
Copper Plastic
Solder Silicon

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Display Options

The following options give you additional control over the display of the MCM design. Color values are in RGB format.

Mono Color
Custom Colors
   Parts 1-4    Perimeter pads
   Parts 5-8    Solder balls
   Package    Leads
   Substrate    Wires
   Interconnect      Ledge
   Lid    Seal ring

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In addition to displaying the graphical image of the MCM this site can generate a file that can be used to directly fabricate a mechanical mockup of the MCM design. The file supports a rapid prototyping manufacturing technology called stereolithography. The file, which has an .stl extension, is ASCII text and consists of the coordinates of the polygons (triangles) which make up the surface of the design.

Manufacturers with stereolithography fabrication equipment can build mechanical mockups of your MCM design in under 24 hours at very reasonable prices! It's an excellent way to go from concept to sample in just a single day! Here are a few links to STL vendors.

For those of you who are not familiar with stereolithography, here are a couple of links to bring you up to speed:

And finally, there are free viewers of STL files at these locations:

Note: the STL file generated by this page includes only the body of the MCM. The I/O (leads, solder balls or perimeter pad) are not included in the STL file that is generated by this page.

Also note that if the display lid option is selected, the STL will still not include the components since they would be covered by the lid. In that case, the interior cavity of the MCM will be filled. If the display lid option is not selected, then the MCM cavity will be open and the components will be included in the STL file (as soon as that feature is completed).