UPE Standard on Heavy Copper Printed Wiring Board Design

A STANDARD DEVELOPED BY UPE CANADA INC.

TABLE OF CONTENTS

1.0 SCOPE PAGE 3
1.1 PURPOSE PAGE 3
1.2 PRESENTATION PAGE 3
1.3 DEFINITIONS PAGE 4
2.0 GENERAL DESIGN CONSIDERATIONS PAGE 5
2.1 END-PRODUCT REQUIREMENTS PAGE 5
2.2 PERFORMANCE CONSIDERATIONS PAGE 5
2.3 MATERIAL TYPE AND PROPERTIES PAGE 5
2.4 MARKINGS, COATINGS AND FINAL FINISH PAGE 6
2.5 INSPECTION AND TRACEABILITY PAGE 7
2.6 ELECTRICAL TESTING PAGE 8
2.7 BOARD SIZE AND TYPE PAGE 8
2.8 DOCUMENTATION AND FILE FORMATS PAGE 9
3.0 SPECIAL DESIGN REQUIREMENTS FOR HEAVY COPPER,
ULTRA THICK, AND PowerLink CIRCUITS
PAGE 10
3.1 BOARD STACK-UP PAGE 10
3.2 CONDUCTOR WIDTH, SPACING AND THICKNESS PAGE 10
3.3 HOLES AND INTERCONNECTIONS PAGE 12
3.4 SOLDER RESIST AND OTHER COATINGS PAGE 13
3.5 NOTATION INK AND OTHER MARKINGS PAGE 13
3.6 PowerLink TECHNOLOGY PAGE 13
APPENDIX A CHARTS AND TABLES PAGE 14
APPENDIX B ENGINEERING DATA PAGE 16

1.0 SCOPE

This standard establishes the special requirements for the design of heavy copper printed wiring boards, ultra thick copper printed wiring boards, PowerLink printed wiring boards and other forms of component mounting and interconnecting structures incorporating copper weights = 3oz/ft2. This standard applies to products manufactured by UPE Canada and is based on current process capabilities of our Carleton Place, Ontario, Canada production facility. Some sections of this standard are guidelines ONLY, and are noted as such. This document is a work in progress and new revisions will be created as our production engineering team incorporates new processes and modifies existing ones. An excellent supplement to this document is IPC-2221 Generic Standard on Printed Wiring Board Design (superseded IPC-D-275) and will be referenced throughout.

1.1 PURPOSE

The requirements contained in this standard are intended to establish design recommendations that are to be used in conjunction with the design principles laid out in IPC-2221. This standard's intended use is by printed wiring board designers who incorporate copper weights ≤ 3oz/ft2 into their products.

1.2 PRESENTATION

All dimensions and tolerances in this standard are in Standard Units unless otherwise noted.

1.3 DEFINITIONS

  • IPC-T-50 - Terms & Definitions for Interconnecting & Packaging Electronic Circuits
  • IPC-SM-840 - Qualification and Performance of Permanent Solder Mask
  • IPC-2221 - Generic Standard on Printed Board Design
  • IPC-6011 - Generic Performance Specification for Printed Boards
  • IPC-6012 - Qualification and Performance Specification for Rigid Printed Boards
  • IPC-4101 - Specification for Base Materials for Rigid Board and Multi-layer Printed Boards
  • IPC-2222 - Sectional Standard on Rigid Organic Printed Boards
  • IPC-9252 - Guidelines and Requirements for Electrical Testing of Unpopulated Printed Boards
  • PowerLink- A technology developed by UPE Canada to allow logic circuits and power circuits (whether connected or non-connected) to occupy the same circuit board layer.
  • Heavy Copper - Term used to identify copper conductors 3 oz/ft2 - 9 oz/ft2.
  • Ultra Thick Copper - Term used to identify copper conductors 10 oz/ft2 or greater.

2.0 GENERAL DESIGN CONSIDERATIONS

This section describes the general parameters to be considered before and during the design of any printed wiring board, but focuses on boards incorporating copper weights ≤ 3oz/ft2. The following parameters can and will have a major impact on reliability and performance of the end product. UPE Canada believes the parameters listed in this section are a MINIMUM to be considered. A comprehensive listing of all parameters and their design/performance tradeoffs is shown in IPC-2221.

2.1 END-PRODUCT REQUIREMENTS

The end product requirements must be known before design start-up. Servicing and maintenance of the end product can directly influence conductor routing, part placement, board size, markings, coatings and final finish.

2.2 PERFORMANCE CONSIDERATIONS

Finished printed wiring boards manufactured by UPE Canada meet or exceed the performance requirements of IPC-6011. There are three general end product performance classes that IPC-6011 has established. Class 1 is "general electronic products", Class 2 is "dedicated service electronic products" and Class 3 is "high reliability electronic products". Please see IPC-6011 or IPC-2221 for more information on the 3 classes. UPE Canada requires all products to be class specified and any exceptions or additions to the specifications to be clearly indicated on the master drawings.

2.3 MATERIAL TYPE AND PROPERTIES

There are several material choices available to the designer, ranging from standard printed wiring board epoxy resins to sophisticated dielectrics with specialized properties. There are a number of properties the designer must consider, including but not limited to; temperature (soldering and operating), electrical properties, structural strength, flame resistance, machinability, CTE, thermal conductivity and thermal stability. Laminate materials should be selected from materials listed in IPC-4101. It is important to note that for high current designs the temperature rise due to current flow in the conductor, when added to all other sources of heat at the conductor/laminate interface, do not exceed the maximum operating temperature specified for the laminate or the assembly. See IPC-2222 for maximum operating temperature for laminate materials. Materials used (prepreg, copper-clad, copper foil, heatsink, etc.) and minimum dielectric thickness/spacing must be specified on the master drawing.

See SECTION 3.1 for more information on build specifications for printed wiring boards incorporating ≤ 3 oz/ft2 copper.

A number of laminate materials and their engineering properties are listed in Appendix B. All of the laminate materials listed in Appendix B are stocked by UPE Canada and are approved by UL for use by UPE Canada. This listing does by no means limit us to their use; please do not hesitate to contact us about your material requirements.

2.4 MARKINGS, COATINGS AND FINAL FINISH

Solder mask is used to provide a hard, durable solder resistant coating that also has electrical insulation properties. UPE Canada applies solder mask coatings in accordance with IPC-SM-840. Solder mask can be used to protect (tent) vias from process solutions and soldering. The maximum finished hole diameter that can effectively be tented is 0.025". Larger hole diameter tenting must be agreed to between the end user and supplier. The electrical insulation properties of solder mask depend on the thickness applied and the type of mask used.

UPE Canada has developed a "capping" process that provides greater electrical insulation properties than regular solder mask. This process involves bonding a thin layer of epoxy resin to specified areas of the completed printed wiring board. Designers must specify how much insulation is required and where the "cap" is to be placed. Please note that surfaces under the "cap" will not be available for soldering.

Designs using copper weights ≤ 3oz/ft2 must meet the design requirements outlined in SECTION 3.4.

All markings and/or legends required by the end user must be specified on the master drawings. The type of marking (non-conductive ink, etched characters, or other methods) must be clearly specified. Markings should be placed to avoid being covered by components and should never be on conductive surfaces. Whenever practical, part number, revision, layer number and orientation markings should be incorporated on the master artwork. Most non-conductive inks are liquid screened and require 0.020" clearance from any solderable surfaces. Please note that liquid screened marking's legibility is affected by high surface irregularities.

Designs using copper weights ≤ 3oz/ft2 must meet the design requirements outlined in SECTION 3.5.

UPE Canada has 4 primary final finishes (3 metallic & 1 organic) that offer corrosion prevention, wear resistance and long-term solderability. Electroplated tin is not included in these four finishes but is used to contribute to the formation of the conductive pattern and in some cases may be used as a final finish.

LISTING 2.41 - FINAL FINISHES

  1. Solder - Applied to the board surface thermally.
  2. Hard Gold - Electroplated gold (cobalt hardener) over electroplated nickel. Primarily used for edge board contacts.
  3. Soft Pure Gold - Immersion (chemically applied) pure gold over electro less (also chemically applied) nickel. Primarily used for wire bonding or to prevent oxidation of the underlying plating.
  4. OSP - Immersion process. Clear, thin organic solderability protective coating (OSP) that protects the underlying plating from oxidation. Useful where flatness is required on surface mount lands. When OSP coatings are used, solderability retention and storage life must be agreed to and documented.

2.5 INSPECTION AND TRACEABILITY

All products manufactured by UPE Canada Inc. are subject to in-process inspections and final inspections in accordance with the performance class specified on the master drawings (See SECTION 2.2). Quality assurance evaluations on finished product normally consist of the following: material, conformance inspections and process control evaluations. Test specimens (coupons) are used as representatives of the printed wiring boards fabricated on the same panel. Coupons are used for most destructive quality evaluations and evaluations that require a specific design that doesn't exist on the printed wiring board. UPE Canada uses coupons on each panel processed for process control evaluation purposes. Layer to layer registration, copper thickness on each layer and in plated through holes, plating adhesion, solderability, soldermask thickness and soldermask adhesion are some of the process parameters evaluated. Material quality assurance is based on statistical sampling normally performed by the material manufacturer. All material that becomes part of the finished product is certified to be in accordance with the master drawing and/or procurement documentation. Conformance evaluations required by the end user must be outlined on the master drawing. The master drawing must include a configuration of the coupon to undergo conformance evaluation. When feasible, coupons are always located in the center of each panel to best reflect plating characteristics. All coupons (whether for conformance or process control evaluations) are identified by board part number, revision, lot number, manufacturer's cage code or logo, and date code.

2.6 ELECTRICAL TESTING

There are several types of bare board electrical testing. Continuity (testing for opens or shorts), insulation resistance (assures sufficient conductor spacing), dielectric withstanding voltage (assures sufficient dielectric thickness), conductor resistance (assures correct conductor cross-sectional area) and capacitance (assures correct dielectric thickness) are some of the electrical tests available. UPE Canada performs all bare board testing according to IPC-9252. There can be a significant cost associated with electrical testing (especially 100% testing), which must be weighed against assembled board price. Some electrical testing (such as conductor resistance) is difficult to perform and is normally only performed on certain customer specified conductors that have a tight operational range.

2.7 BOARD SIZE AND TYPE

There is a limit to the size of board that can be produced. This limitation is mainly due to equipment factors. UPE Canada uses several different panel sizes in order to maximize manufacturability and minimize costs. A larger panel size will decrease labor cost per unit but can have a detrimental effect on yield due to difficulties in achieving fine lines and positional accuracy. The panel size used depends on a number of factors including: circuit complexity, pallet size or board size, number of layers, copper weight, and process parameters. The engineering department of UPE Canada chooses the production panel size during contract review.

The maximum board sizes that UPE Canada can currently process are shown in TABLE 2.71.

TABLE 2.71 - MAXIMUM BOARD SIZE

Board Type Maximum Dimensions (inches)
Single-Sided / Double-Sided 16.60" X 22.60"
Multi layer 16.30" X 22.30"

The decision for board type (single-sided, double-sided, or multi-layer) should be based on electrical performance, circuit density, and mechanical requirements.

Balanced circuitry distribution on each copper layer and symmetrical construction are important to minimize the degree of bow and twist of a circuit board (See IPC-6011 for values and measurement parameters). The cross-sectional layout, which includes core thickness, dielectric thickness, inner layer planes, and individual copper layer thicknesses, should be kept as symmetrical as possible about the center of the board. When tighter tolerances for bow and twist are required to meet assembly or performance criteria, some sort of support hardware may be necessary.

Designs using copper weights ≤ 3oz/ft2 must meet the design requirements outlined in SECTION 3.2.

2.8 DOCUMENTATION AND FILE FORMATS

Documentation packages should consist of a master drawing and copies of the artwork masters. The package may be provided in either hard copy or electronic data. The layout should always be drawn as viewed from the primary side of the board. All drawings and electronic files should be identified with the board part number and revision status. Notes are especially important for the engineering review; outlining non-standard tolerances, plating requirements, board stack-up, and inspection criteria.

UPE Canada prefers that all master artwork be sent in Gerber RS-274X (with embedded apertures) electronic file format. Note that we support direct input from various design packages in addition to Gerber. Please contact us with any special electronic file requirements. All other electronic data (drawings, specifications, assembly part lists, etc.) may be sent in a variety of file formats although some (such as DXF and DWG) are preferred.

3.0 SPECIAL DESIGN REQUIREMENTS FOR HEAVY COPPER, ULTRA THICK, AND POWERLINK CIRCUITS

This section describes the unique design requirements for printed wiring boards incorporating copper weights ≤ 3oz/ft2. Most of the requirements in this section relate directly to printed wiring boards manufactured by UPE Canada. Designs using copper weights ≤ 3oz/ft2 will be subject to these requirements due to the nature of the production processes involved and the impact these requirements have on the end product's performance and reliability.

3.1 BOARD STACK-UP

A cross-sectional build diagram showing dielectric thicknesses and copper thicknesses is called a board stack-up. The board stack-up should be included on the master drawing along with any special build requirements. See Diagram 3.11 for reference. Note that the board stack-up must include a nominal value with tolerances for each separation and copper thickness. A minimum value may be used alternatively. The total board thickness tolerance is a cumulative total of all internal tolerances. In certain situations where a component or mounting point has a specific thickness requirement different than the rest of the board, please note it in the engineering notes on the master drawing.

Diagram 3.11 - Build Diagram Example

3.2CONDUCTOR WIDTH, SPACING AND THICKNESS

The minimum width and thickness of a conductor is determined primarily on the basis of the current carrying capacity required and the maximum permissible conductor temperature rise. The minimum conductor width and thickness should be in accordance with FIGURE A.2 in Appendix A. The conductor's permissible temperature rise is defined as the difference between the maximum safe operating temperature of the laminate material and maximum temperature of the thermal environment to which the board is subjected.

The conductor thickness of copper layers (internal or external) includes a copper foil thickness and a plated copper thickness (in most cases) deposited during the plate through hole process. If conductor thickness is critical, a minimum finished conductor thickness on each layer and in holes must be specified on the master drawing. There is a maximum thickness of 6 oz/ft2 for internal copper layers when using epoxy based laminate material. The reason for this limitation is an inability of the epoxy resin to completely encapsulate all internal conductors of thickness greater than 0.0085".

Conductors should be spaced out as much as possible on individual layers provided there is space available. There is a minimum allowable conductor spacing (this includes layer to layer) requirement for all printed wiring boards when a certain voltage is applied. See FIGURE 3.22 for minimum conductor spacing versus voltage. When a minimum conductor spacing requirement arises due to a voltage constraint; it must be defined on the master drawing.

Producing printed wiring boards incorporating copper weights ≤ 3 oz/ft2 require specialized processes that have been developed by UPE Canada. These processes have tolerances and limitations associated with them. Our experience has shown that there are minimum conductor widths and spaces that can be processed for specific copper weights. CHART A1 (in Appendix A) shows these minimums and the tolerances associated with them. In order to achieve copper weights ≤ 3 oz/ft2, UPE Canada must plate copper in an additive process or etch copper in a subtractive process. The process tolerances for both of these procedures increase as the copper weight increases. Larger bilateral tolerances for conductor width and spacing width as well as the tolerance for finished conductor thickness are the result as copper weights increase. A typical bilateral tolerance for a 1oz/ft2 conductor is +/- 0.002". CHART A1 shows the bilateral tolerance for a conductor of copper weights from 1 oz/ft2 - 30 oz/ft2. Tighter bilateral tolerances must be agreed to between UPE Canada and the end user before production can begin. Any tolerances, conductor widths, and conductor spacing conflicting with CHART A1 must be approved by UPE Canada and stated on the master drawing.

TABLE 3.22 - MINIMUM CONDUCTOR SPACING vs. VOLTAGE PEAK

Voltage DC or AC peaks Minimum Spacing (inches)
Bare Board Assembly
B1 B2 B3 B4 A5 A6 A7
0-15 0.00197 0.00394 0.0394 0.00197 0.00512 0.00512 0.00512
16-30 0.00197 0.00394 0.0394 0.00197 0.00512 0.00984 0.00512
31-50 0.00394 0.0236 0.0236 0.00512 0.00512 0.0157 0.00512
51-100 0.00394 0.0236 0.0591 0.00512 0.00512 0.0197 0.00512
101-150 0.00787 0.0236 0.126 0.0157 0.0157 0.0315 0.0157
151-170 0.00787 0.0492 0.126 0.0157 0.0157 0.0315 0.0157
171-250 0.00787 0.0492 0.252 0.0157 0.0157 0.0315 0.0157
251-300 0.00787 0.0492 0.492 0.0157 0.0157 0.0315 0.0315
301-500 0.00984 0.0984 0.492 0.0315 0.0315 0.0591 0.0315
>500 0.00984 +
[(volts-500) X0.0000984]
0.00984 +
[(volts-500) X0.0000984]
0.00984 +
[(volts-500) X0.0000984]
0.00984 +
[(volts-500) X0.0000984]
0.00984 +
[(volts-500) X0.0000984]
0.00984 +
[(volts-500) X0.0000984]
0.00984 +
[(volts-500) X0.0000984]

B1 -Internal Conductors
B2 - External Conductors, uncoated, sea level to 3050m
B3 - External Conductors, uncoated, over 3050m
B4 - External Conductors, with permanent polymer coating (any elevation)
B5 - External Conductors, with conformal coating over assembly (any elevation)
A6 - External Component lead/termination, uncoated
A7 - External Component lead termination, with conformal coating (any elevation)

3.3 HOLES AND INTERCONNECTIONS

All lands (conductor pads) and annular rings should be maximized whenever possible provided that good design practice and all electrical spacing requirements are met. The minimum pad diameter surrounding a supported (PTH) or unsupported (NPT) hole must be determined by using CHART A.1 (in Appendix A). Please note that the pad diameters apply to external and internal pads. Internal clearances must adhere to the minimum spacing required for the external copper weight in which the PTH hole is located. Class 3 designs incorporating copper weights ≤ 3 oz/ft2 must strive for the "ideal" pad diameter since this class of product doesn't allow for breakouts. The performance specifications for Class 1 and Class 2 may allow for partial breakouts (see IPC-6011). Circular pads are most common, but it should be noted that other pad shapes could be used to increase spacing and therefore producability. Fillets, keyholing, and corner entry pad shapes may be used provided breakout is allowed.

The thickness of copper in the barrel of the plated through hole and the thickness of copper on the external surface will not be the same in most cases. The minimum copper thickness in the barrel of a plated through hole is 0.0008". UPE Canada Inc. allows for a copper thickness of 0.0020" in the barrel, although any thickness is achievable. Note any minimum PTH copper thickness requirement on the master drawing.

3.4 SOLDER RESIST AND OTHER COATINGS

Section 2.4 pointed out the ability of solder mask to act as an electrical insulator. UPE Canada has developed application techniques that allow for multiple coats of solder mask without affecting solderability or solder mask adhesion. Please contact our engineering department with any special solder mask requirements.

UPE Canada strongly recommends all designs with copper weights greater than 3 oz/ft2 (on internal or external layers) to employ solder mask on external layers due to the high temperature requirements when soldering. The solder mask acts as a thermal barrier to the laminate material; enabling pads and lands to heat up faster. All solder mask clearance diameters must comply with CHART A.1.

UPE Canada has developed a "capping" process that provides greater electrical insulation properties than regular solder mask. This process involves bonding a thin layer of epoxy resin to specified areas of the completed printed wiring board. Designers must specify how much insulation is required and where the "cap" is to be placed. Please note that surfaces under the "cap" will not be available for soldering. Please contact our engineering department about this new and innovative technology.

3.5 NOTATION INK AND OTHER MARKINGS

Copper weights greater than 3 oz/ft2 on external layers will have an adverse affect on notation ink's legibility. In order for important assembly information and labeling to be legible, we recommend that all markings be on a non-conductor area at least 0.100" from a conductor edge and/or entirely on top of a ground plane area or large conductor. All liquid screened markings must be at least 0.010" in width in order for various letter fonts to be readable.

3.6 PowerLink TECHNOLOGY

PowerLink is a technology UPE Canada has developed that allows multiple copper weights to occupy the same layer of circuitry. This technology enables the designer to have logic circuits and power circuits on the same plane. All of the design requirements covered in this standard apply to designs incorporating PowerLink. One special note: Conductor spacing between different copper weights must follow CHART A.1 for the greater copper weight.

There are a number of special design requirements for PowerLink; please contact our engineering department if you are planning on using this technology in a build.

APPENDIX A CHARTS AND TABLES

FIGURE A.2 - CONDUCTOR THICKNESS AND WIDTH FOR INTERNAL AND EXTERNAL LAYERS

APPENDIX B ENGINEERING DATA ON VARIOUS LAMINATE MATERIALS

Chart B.1 Arlon 33N Polyimide Engineering Properties

Non-MDA chemistry
UL94V-0 flame retardant

Property Test Method Result
Peel strenght lb/in elev. Temp.(Kg/m)-14 Mil Lam IPC-TM-650 2.4.8 10.7(190)
Peel after process solutions lb/in(Kg/m)-14 Mil Lam IPC-TN-650 2.4.8 9.0(160)
Tq(degrees C) IPC-TM-650 2.4.24(TMA) >250
CTE-Z axis(ppm/degrees C) IPC-TM-650 2.4.24(TMA) 55
CTE-X,Y axis(ppm/degrees C) IPC-TM-650 2.4.24(TMA) 16-17
Permitivity(DK)(1 MHz) IPC-TM-650 2.5.5.3 4.2
Loss Tangent(1 MHz) IPC-TM-650 2.5.5.3 0.012
Flammability UL94 V-0
Volume Resistivity(megaohm-cm) IPC-TM-650 2.5.17.1 7x109
Surface Resistivity(megaohms) IPC-TM-650 2.5.17.1 2x108
Flexural Strength Elev. Temp. psi(Kg/m)-31 Mil Lam IPC-TM-650 2.4.4 77.668(5.4x107)
Electrical Strength(volts/mil) IPC-TM-650 2.5.6.2 1150
Water Absorption % IPC-TM-650 2.6.2.1 0.24%

Data from ARLON electronic substrates website: www.arlonmed.com

Chart B.2 Park/Nelco N5000 BT-Epoxy Engineering Properties

UL94V-0 flam retardant

Property Test Method Result
Peel strenght lb/in-1oz Cu after solder float IPC-TM-650 2.4.8 8.9
Peel strength lb/in-1oz Cu after process solutions IPC-TN-650 2.4.8 9.4
Tq(degrees C) IPC-TM-650 2.4.25c 185
CTE-Z axis IPC-TM-650 2.4.41 3.80%
CTE-X,Y axis(ppm/degrees C) IPC-TM-650 2.4.41 10-14
Permitivity(DK)(1 MHz) IPC-TM-650 2.5.5.3 4.1
Loss Tangent(1 MHz) IPC-TM-650 2.5.5.3 0.013
Flammability UL94 V-0
Volume Resistivity(megaohm-cm) IPC-TM-650 2.5.17.1 107
Surface Resistivity(megaohms) IPC-TM-650 2.5.17.1 106
Dielectric Breakdown kV IPC-TM-650 2.5.6 >50
Electrical Strength(volts/mil) IPC-TM-650 2.5.6.2 1200
Water Absorption % IPC-TM-650 2.6.2.2c <0.05%

Chart B.3 Isola multigunctionsal FR4Engineering Properties

UL94V-0 flam retardant

Property Test Method Result
Peel strenght lb/in-1oz Cu after solder float IPC-TM-650 2.4.8 8.0
Peel strength lb/in-1oz Cu after process solutions IPC-TN-650 2.4.8 8.0
Tq(degrees C) IPC-TM-650 2.4.25c 150
CTE-Z axis(ppm/degrees C) IPC-TM-650 2.4.41 155
CTE-X,Y axis(ppm/degrees C) IPC-TM-650 2.4.41 14
Permitivity(DK)(1 MHz) IPC-TM-650 2.5.5.3 4.7
Loss Tangent(1 MHz) IPC-TM-650 2.5.5.3 0.025
Flammability UL94 V-0
Volume Resistivity(megaohm-cm) IPC-TM-650 2.5.17.1 1x108
Surface Resistivity(megaohms) IPC-TM-650 2.5.17.1 2x108
Electrical Strength(volts/mil) IPC-TM-650 2.5.6.2 1350
Water Absorption % IPC-TM-650 2.6.2.2c 0.20

Data from Isola electronic substrates website: www.isola.com

Chart B.4 Isola Multifunctional High Performance FR4 Engineering Properties

UL94V-0 flame retardant

Property Test Method Result
Peel strenght lb/in-1oz Cu after solder float IPC-TM-650 2.4.8 6.0
Peel strength lb/in-1oz Cu after process solutions IPC-TN-650 2.4.8 8.0
Tq(degrees C) IPC-TM-650 2.4.25c 170
CTE-Z axis(ppm/degrees C) IPC-TM-650 2.4.41 140
CTE-X,Y axis(ppm/degrees C) IPC-TM-650 2.4.41 14
Permitivity(DK)(1 MHz) IPC-TM-650 2.5.5.3 4.6
Loss Tangent(1 MHz) IPC-TM-650 2.5.5.3 0.023
Flammability UL94 V-0
Volume Resistivity(megaohm-cm) IPC-TM-650 2.5.17.1 9x106
Surface Resistivity(megaohms) IPC-TM-650 2.5.17.1 8x106
Electrical Strength(volts/mil) IPC-TM-650 2.5.6.2 1000
Water Absorption % IPC-TM-650 2.6.2.2c 0.20