Microvia Checks

HDI Drill (Microvia) Analysis

Provides advanced drill analysis for HDI design. This includes more detailed drill checks with respect to the special microvia requirements. Signal layer and soldermask-related issues are checked as well.

Microvia Checks assumes that the laser drill is drilled from the outermost layer.

Definitions

Drill Type is defined according to the .drill attribute value (PTH, NPTH, Via). If a hole has no .drill attribute , the default is PTH for through drills and Via for blind/buried drills. In addition, vias can be further classified according to the .via_type attribute (Standard/Micro). If a via hole has no .via_type attribute, the default is Standard.

Check parameters are computed implicitly according to the relevant ranges. For example, the maximal PTH to Via spacing reported is the green value of the category pth2via_spacing .

All spacings are measured edge-to-edge.

Aspect Ratio (diameter-to-depth) is computed according to the .depth (drill) layer attribute, which should keep the total board thickness pierced by this drill layer (the actual drill depth). If not defined, a maximal depth for the minimal (red) aspect ratio will be reported per drill diameter/type.

Annular Ring/Missing Pad side (top/bottom) refers to the job matrix and not to the actual drill direction.

Drill-to-copper spacing is reported only when a drill does not touch copper, and annular ring is reported only when a drill is fully covered by copper. Otherwise, drill-touches-copper is reported.

Measurements reported by checks from the Drill Test list are added to input drill layers. Measurements reported by checks from Signal and SM Test lists are added to the corresponding Signal/SM layer.

Tests

Drill Test List

Drill-related checks that can be applied to drill layers.

*        Spacing - reports spacing between all drills from the input layer and all drill layers piercing at least one common board layer (including the input layer itself).

*        Overlap - reports overlap (full or partial) between all drills from the input layer and all drill layers piercing at least one common board layer (including the input layer itself).

*        Spatial Spacing - reports spacing between all drills from the input layer and all drill layers terminating on adjacent board layers and NOT piercing a common board layer (for blind/buried drills only).

*        Spatial Overlap - reports overlap between all drills from the input layer and all drill layers terminating on adjacent board layers and NOT piercing a common board layer (for blind/buried drills only).

*        Aspect Ratio - reports aspect ratio and/or maximum drill depth.

Signal Test List

Signal-related checks that can be applied to drill layers relative to signal layers pierced by input drill layers.

*        Annular Ring - reports annular ring and copper crossed by drill.

*        Copper Spacing - reports drill-to-copper spacing.

*        Missing Pad - reports missing pads for drills.

*        Registration - reports drills misregistered relative to pads.

SM Test List

Soldermask-related checks that can be applied to drill layers. Top/bottom soldermask layers will be checked only if the input drill layer pierces a top/bottom board layer. (Genesis assumes that soldermask layers are outer layers.)

*        Annular Ring - reports annular ring and soldermask crossed by drill.

*        Coverage - reports drill-to-soldermask spacing.

*        Covered Drills - reports covered drills.

 

Attributes

Attribute

Description

...min_X2Y_spacing

minimal spacing between drills (X and Y are one of PTH, NPTH, Via, Microvia)

...typ_X2Y_spacing

typical spacing between drills (X and Y are one of PTH, NPTH, Via, Microvia)

...num_X2Y_overlap

number of overlaps between drills (X and Y are one of PTH, NPTH, Via, Microvia)

...min_X2Y_spatial_spacing

minimal spatial spacing between drills  (X and Y are one of PTH, Via, Microvia)

...typ_X2Y_spatial_spacing

typical spatial spacing between drills (X and Y are one of PTH, Via, Microvia)

...num_X2Y_spatial_overlap

number of spatial overlaps between drills (X and Y are one of PTH, Via, Microvia)

...min_X_Y_ar

minimal signal annular ring (X is one of PTH, Via, Microvia, Y is one of top, bottom, inner)

...typ_X_Y_ar

typical signal annular ring (X is one of PTH, Via, Microvia, Y is one of top, bottom, inner)

...min_npth_ar

minimal signal annular ring for NPTH

...typ_npth_ar

typical signal annular ring for NPTH

...min_X2cu_spacing

minimal drill to copper spacing on signal layer (X is one of PTH, NPTH, Via, Microvia)

...typ_X2cu_spacing

typical drill to copper spacing on signal layer  (X is one of PTH, NPTH, Via, Microvia)

...num_X_missing_Y_pad

number of drills with no pads on the corresponding signal layer 

(X is one of PTH, Via, Microvia; Y is one of top, bottom, inner)

...num_npth_missing_pad

number of NPTHs with no pads on signal layer

...num_X_crosses_cu

number of drills crossing copper  (X is one of PTH, NPTH, Via, Microvia)

...min_X_reg

minimal drill misregistration relative to the signal layer (X is one of PTH, NPTH, Via, Microvia)

...typ_X_reg

typical drill misregistration relative to the signal layer (X is one of PTH, NPTH, Via, Microvia)

...min_X_sm_ar

minimal soldermask annular ring (X is one of PTH, Via, Microvia)

...typ_X_sm_ar

typical soldermask annular ring  (X is one of PTH, Via, Microvia)

...num_X_crosses_sm

number of drills crossing soldermask (X is one of PTH, NPTH, Via, Microvia)

...num_X_covered

number of drills covered by soldermask  (X is one of PTH, Via, Microvia)

...min_X_coverage

minimal drill to soldermask opening spacing on soldermask layer

(X is one of PTH, NPTH, Via, Microvia)

...typ_X_coverage

typical drill to soldermask opening spacing on soldermask layer (X is one of PTH, NPTH, Via, Microvia)

...min_X_aspect_ratio

minimal aspect ratio (X is one of PTH, Via, Microvia)

...typ_X_aspect_ratio

typical aspect ratio (X is one of PTH, Via, Microvia)

...min_X_max_depth

minimal max depth (X is one of PTH, Via, Microvia)

  

Categories

X-to-Y Spacing (Drill Test List / Spacing)-X and Y are one of: PTH, NPTH, Via, Microvia .

Item

Details

Full Name

X-to-Y Spacing

Internal ERF Name

X2Y_spacing

Measurement Shape

Segment

Measurement ID(s)

Pads representing two drills

Layers Displayed

Drill layer(s)

Picture

 

Purpose

To ensure sufficient drill-to-drill spacing on a board layer.

Function

Report spacing between all drills from the input layer and all drill layers piercing at least one common board layer (including the input layer itself). Max spacing to search is defined by the green range value of the category.

Activation

Spacing check in Drill Test List is selected.

Known Limitations

 

 

X-to-Y Overlap (Drill Test List / Overlap)-X and Y are one of: PTH, NPTH, Via, Microvia .

Item

Details

Full Name

X-to-Y Overlap

Internal ERF Name

X2Y_overlap

Measurement Shape

Segment

Measurement ID(s)

Pads representing two drills

Layers Displayed

Drill layer(s)

Picture

 

Purpose

To find overlapping drills on a board layer.

Function

Reports overlaps (full or partial) between all drills from the input layer and all drill layers piercing at least one common board layer (including the input layer itself).

Activation

Overlap check in Drill Test List is selected.

Known Limitations

 

X-to-Y Spatial Spacing (Drill Test List / Spatial Spacing) - X and Y are one of: PTH, Via, Microvia ..

Item

Details

Full Name

X-to-Y Spatial Spacing

Internal ERF Name

X2Y_spatial_spacing

Measurement Shape

Segment

Measurement ID(s)

Pads representing two drills

Layers Displayed

Drill layer(s)

Picture

 

Purpose

To ensure sufficient drill-to-drill spacing on adjacent board layers where the drills terminate.

Function

Reports spacing between all drills from the input layer and all drill layers terminating on adjacent board layers and NOT piercing a common board layer. Max spacing to search is defined by the green range value of the category.

Activation

Spatial Spacing check in Drill Test List is selected and both drill layers are blind/buried.

Known Limitations

 

X-to-Y Spatial Overlap (Drill Test List / Spatial Overlap) - X and Y are one of: PTH, Via, Microvia .

Item

Details

Full Name

X-to-Y Spatial Overlap

Internal ERF Name

X2Y_spatial_overlap

Measurement Shape

Segment

Measurement ID(s)

Pads representing two drills

Layers Displayed

Drill layer(s)

Picture

 

Purpose

To find overlapping drills on adjacent board layers where the drills terminate.

Function

Reports overlaps (full or partial) between all drills from the input layer and all drill layers terminating on adjacent board layers and NOT piercing a common board layer.

Activation

Spatial Overlap check in Drill Test List is selected and both drill layers are blind/buried.

Known Limitations

 

X Aspect Ratio (Drill Test List / Aspect Ratio) - X is one of: PTH, Via, Microvia .

Item

Details

Full Name

X Aspect Ratio

Internal ERF Name

X_aspect_ratio

Measurement Shape

Circle

Measurement ID(s)

Pads representing drill

Layers Displayed

Drill layer

Picture

 

Purpose

To ensure that the aspect ratio fits the process requirements.

Function

Reports aspect ratio for all drills if v_compute_typ_aspect_ratio = yes, and for one drill of each symbol of the given type if
v_compute_typ_aspect_ratio = no.

Activation

Aspect Ratio check in Drill Test List is selected and the .depth attribute is defined for the drill layer.

Known Limitations

 

X Max Depth (Drill Test List / Aspect Ratio) -X is one of: PTH, Via, Microvia .

Item

Details

Full Name

X Max Depth

Internal ERF Name

X_max_depth

Measurement Shape

Circle

Measurement ID(s)

Pads representing drill

Layers Displayed

Drill layer

Picture

 

Purpose

To ensure that the aspect ratio fits the process requirements.

Function

Reports max depth for drill according to the min allowed (red) aspect ratio for all drills if
v_compute_typ_aspect_ratio = yes , and for one drill of each symbol of the given type if
v_compute_typ_aspect_ratio = no.

Activation

Aspect Ratio check in Drill Test List is selected and the .depth attribute is not defined for the drill layer, or
v_always_check_max_depth = yes .

Known Limitations

 

X Y Annular Ring (Signal Test List / Annular Ring) -X is one of PTH, Via, Microvia, Y is one of: Top, Bottom, Inner .

Item

Details

Full Name

X Y Annular Ring

Internal ERF Name

X_Y_ar

Measurement Shape

Segment

Measurement ID(s)

Signal Layer shape and Pad representing a drill.

Layers Displayed

Signal Layer and Drill layer

Picture

 

Purpose

To ensure sufficient annular ring.

Function

Reports drills where the annular ring on the corresponding signal layer is less than the green range value of the category. The side of the layer (top/bottom/inner) is relative to the drill layer as defined in the job matrix.

Activation

Annular Ring check in Signal Test List is selected.

Known Limitations

 

NPTH Annular Ring (Signal Test List / Annular Ring)

Item

Details

Full Name

NPTH Annular Ring

Internal ERF Name

NPTH_ar

Measurement Shape

Segment

Measurement ID(s)

Signal Layer shape and Pad representing an NPTH

Layers Displayed

Signal Layer and Drill layer

Picture

 

Purpose

To ensure sufficient annular ring

Function

Reports non-plated drills where the annular ring on the corresponding signal layer is less than the green range value of the category.

Activation

Annular Ring check in Signal Test List is selected.

Known Limitations

 

 

X Crosses Copper (Signal Test List / Annular Ring -X is one of: PTH, NPTH, Via, Microvia .

Item

Details

Full Name

X Crosses Copper

Internal ERF Name

X_crosses_cu

Measurement Shape

Circle

Measurement ID(s)

Signal Layer shape and Pad representing a drill

Layers Displayed

Signal Layer and Drill layer

Picture

 

Purpose

To find drills crossing copper on a signal layer.

Function

Reports drills partially covered by copper.

Activation

Annular Ring check in Signal Test List is selected.

Known Limitations

 

X Missing Y Pad (Signal Test List / Missing Pad)- X is one of: PTH, Via, Microvia ; Y is one of: Top, Bottom, Inner .

 

Item

Details

Full Name

X Missing Y Pad

Internal Name

X_missing_Y

Measurement Shape

Circle

Measurement ID(s)

Pad representing a drill

Layers Displayed

Signal Layer and Drill layer

Picture

 

Purpose

To ensure that drill is covered by pad/copper.

Function

Reports drills with no pad in the corresponding signal layer.
If
v_require_pad_X = no , only drills which are not covered by copper will be reported. Also, the value of v_missing_pad_X_mode is considered with respect to the layer side relative to the drill layer as defined in the job matrix.

Activation

Missing Pad check in Signal Test List is selected.

Known Limitations

 

NPTH Missing Pad (Signal Test List / Missing Pad)

Item

Details

Full Name

NPTH Missing Pad

Internal ERF Name

npth_missing

Measurement Shape

Circle

Measurement ID(s)

Pad representing a drill

Layers Displayed

Signal Layer and Drill layer

Picture

 

Purpose

To ensure that drill is covered by pad/copper.

Function

Reports NPTH drills with no pad in the corresponding signal layer.

Activation

Missing Pad check in Signal Test List is selected and v_check_missing_pad_npth = yes .

Known Limitations

 

X-to-Copper Spacing (Signal Test List / Copper Spacing) - X is one of: PTH, NPTH, Via, Microvia .

Item

Details

Full Name

X-to-Copper Spacing

Internal ERF Name

X2cu_spacing

Measurement Shape

Segment

Measurement ID(s)

Pad representing a drill and Signal Layer shape

Layers Displayed

Signal Layer and Drill layer

Picture

 

Purpose

To ensure sufficient spacing from drill to (unconnected) copper.

Function

Reports drills close to the copper which do not cover it. Max spacing to search is defined by the green range value of the category.
If
v_report_all_spacings = yes , then all spacing violations (less then max) are reported. Otherwise only the smallest spacing violation is reported.

Activation

Copper Spacing check in Signal Test List is selected.

Known Limitations

 

  

X Registration (Signal Test List / Registration) - X is one of: PTH, NPTH, Via, Microvia .

Item

Details

Full Name

X Registration

Internal ERF Name

X_reg

Measurement Shape

Segment

Measurement ID(s)

Pad representing a drill and Signal Layer pad

Layers Displayed

Signal Layer and Drill layer

Picture

 

Purpose

To ensure drill registration relative to the corresponding signal layer pad.

Function

Reports drills misregistered relative to the corresponding pad in the signal layer (drill and pad have different centers). Max misregistration to search is defined by the green range value of the category.

Activation

Registration check in Signal Test List is selected.

Known Limitations

 

X SM Annular Ring (SMTest List / Annular Ring) - X is one of: PTH, Via, Microvia .

Item

Details

Full Name

X SM Annular Ring

Internal ERF Name

X_sm_ar

Measurement Shape

Segment

Measurement ID(s)

SM Layer shape and Pad representing a drill

Layers Displayed

SM Layer and Drill layer

Picture

 

Purpose

To ensure sufficient annular ring.

Function

Reports drills where the annular ring on the corresponding sm layer is less than the green range value of the category.

Activation

Annular Ring check in SM Test List is selected and the drill layer pierces (at least one) outer layer.

Known Limitations

 

X Crosses SM (SM Test List / Annular Ring) - X is one of: PTH, NPTH, Via, Microvia .

Item

Details

Full Name

X Crosses SM

Internal ERF Name

X_crosses_sm

Measurement Shape

Circle

Measurement ID(s)

SM Layer shape and Pad representing a drill

Layers Displayed

SM Layer and Drill layer

Picture

 

Purpose

To find drills crossing solder.

Function

Reports drills partially covered by soldermask.

Activation

Annular Ring check in SM Test List is selected.

Known Limitations

 

Covered X (SM Test List / Covered Drills) - X is one of: PTH, Via, Microvia .

Item

Details

Full Name

Covered X

Internal ERF Name

X_covered

Measurement Shape

Circle

Measurement ID(s)

Pad representing a drill

Layers Displayed

SM Layer and Drill layer

Picture

 

Purpose

To ensure that the drill which pierces the outer layer is exposed by the corresponding soldermask.

Function

Reports drills which are covered by the soldermask (there are no shapes covering the drill in the corresponding sm layer).

Activation

Covered Drills check in SM Test List is selected and the drill layer pierces (at least one) outer layer.

Known Limitations

 

 

X Coverage (SM Test List / Coverage) - X is one of: PTH, NPTH, Via, Microvia .

Item

Details

Full Name

X Coverage

Internal ERF Name

X_coverage

Measurement Shape

Segment

Measurement ID(s)

Pad representing a drill and SM Layer shape

Layers Displayed

SM Layer and Drill layer

Picture

 

Purpose

To ensure sufficient spacing from drill to the soldermask opening.

Function

Reports drills close to the soldermask opening which do not expose that drill. Max spacing to search is defined by the green range value of the category.
If
v_report_all_coverages=yes , then all spacing violations (less then max) are reported. Otherwise only the smallest spacing violation is reported.

Activation

Copper Spacing check in Signal Test List is selected.

Known Limitations