Electronic & Electrochemical Materials

GORE® EMI Shielding Materials: GS8000 Series - Gaskets and Grounding Pads

GORE-SHIELD® GS8000 EMI Gaskets

Increase package design flexibility while maintaining electrical integrity

The GS8000 Series of GORE® EMI Shielding Materials improves package design flexibility without compromising the electrical performance of the device. These highly compressible materials are specifically engineered to maintain consistent conductivity through a wide working range (see Figure 1 and Figure 2 below).


With Gore’s strong technology focus in materials, the GS8000 Series was developed with a unique conductive foam. The soft conductive foam construction accommodates surface variations in covers and printed circuit boards, alleviating the need to specify very tight tolerances. This soft construction also makes the GS8000 Series compatible with plastic housings and snap fasteners. This material maintains excellent shielding performance in a trace width as narrow as 1 mm, providing comparable performance to other EMI shielding materials that are 3 times the width. With the lower compression or closure force, fewer fasteners are needed.

Available as grounding pads and precision die-cut parts that enable precise, high-volume assembly, the GS8000 Series of GORE® EMI Shielding Materials provide maximum cavity-to-cavity EMI protection in a smaller size for more design flexibility.

Available as custom die-cut gaskets, strip gaskets, and grounding pads


Typical Applications

  • Portable electronic devices, mobile phones, and GPS
  • Portable computers
  • Hand-held field testing equipment

Features and Benefits

  • Unsurpassed shielding effectiveness and minimal DC resistance with low compressive force and broad range of tolerance take-up
  • Reliable electrical performance over wide range of gap distances from soft foam construction
  • Effective shielding performance in trace widths as narrow as 1 mm
  • Improved design flexibility because of low closure force

Environmental and Mechanical Properties

Property  Value
Temperature range - 45°C to 85°C
RoHS Status (lead, cadmium, hexavalent chromium, mercury, bromine)  Pass
Flammability in accordance with UL 94 horizontal burn method Pass
Halogen levels (measured per BS EN 14582:2007)  
  Chlorine < 50 ppm
  Bromine < 50 ppm
  Fluorine < 50 ppm
  Iodine < 50 ppm
Typical working range (for grounding pads)  0.15 mm to 2.2 mm (0.006" to 0.087")
Typical working range (for EMI gaskets)  0.15 mm to 1.4 mm (0.006" to 0.055")
Typical pressure to recommended compression stop (RCS)  20 to 50 psi

Extended Service Heights

The GS8000 Series of GORE® EMI Shielding Materials performs wellin both grounding and EMI shielding applications. Gore recommendsusing each variant within a range of service heights (gap distances).For shielding applications, Gore recommends a smaller service heightrange than for grounding applications to ensure a robust EMI seal.

The low closure force and broad range of tolerance take-up results inmultiple product choices for some gap distances. Selecting the mostsuitable variant for a given application depends on:

  1. Gap distance of the housing that needs to be filled
  2. Compression force required to achieve the specified gap distance
  3. Required DC resistance for grounding applications (or required shielding effectiveness for shielding applications) at a specified gap distance

Figure 1 and Figure 2 show recommended service heights (gap distances) for each variant.

Figure 1: Recommended Service Heights for Use in EMI Gasket Applications

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Figure 2: Recommended Service Heights for Use in EMI Grounding Pads

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Force and DC Resistance

Three of the variants among the GS8000 Series provide conductivity when compressed to 0.6 mm (0.24 in); however, the amount of force and DC resistance varies for each. The table below shows the values for each of these three variants.

Force and DC Resistance Values at 0.6 mm Gap (see datasheet for more detail)

Variants Force Required (psi) DC Resistance (ohms)
GS8000-063 15 0.03
GS8000-095 50 0.02
GS8000-126 85 0.01

 

Product Specifications (measured on 5 x 5 mm grounding pads)

Variants Weight (g) Compression Stop Compression Stop
mm (in)		 Pressure to Achieve Compression (psi) Initial DC Resistance (ohms) Recovered Thickness
mm (in)1
GS8000-03X 0.008 High
Recommended
Low		 0.45 (0.018)
0.30 (0.012)
0.15 (0.006)		 5
80
380		 0.245
0.125
0.015		 0.56 (0.022)
0.38 (0.015)
0.25 (0.010)
GS8000-063 0.010 High
Recommended
Low		 0.90 (0.035)
0.60 (0.024)
0.30 (0.012)		 5
20
100		 0.070
0.025
0.007		 1.19 (0.047)
0.91 (0.036)
0.51 (0.020)
GS8000-095 0.011 High
Recommended
Low		 1.20 (0.047)
0.85 (0.033)
0.50 (0.020)		 4
20
100		 0.115
0.040
0.010		 1.65 (0.065)
1.24 (0.049)
0.74 (0.029)
GS8000-126 0.013 High
Recommended
Low		 2.20 (0.087)
1.40 (0.055)
0.60 (0.024)		 1
4
80		 0.240
0.150
0.012		 2.62 (0.103)
1.90 (0.075)
0.94 (0.037)

1 To measure the recovered thickness, samples were compressed to the compression stop. While compressed, the samples were subjected to a 70°C temperature soak for 70 hrs per ASTM D395B. Lastly, the samples were released from compression and allowed to recover for 30 minutes before the recovered thickness was measured.
 

For use as an EMI Gasketing Material, we recommend compressing the GS8000 material to at least the published recommended compression stop to ensure an effective EMI seal (see table below).

Shielding Effectiveness

Variants Compression Stop Compression Stop
mm (in)		 Shielding Effectiveness1
GS8000-03X Recommended
Low		 0.30 (0.012)
0.15 (0.006)		 > 50 dB
> 65 dB
GS8000-063 Recommended
Low		 0.60 (0.024)
0.30 (0.012)		 > 90 dB
> 100 dB
GS8000-095 Recommended
Low		 0.85 (0.033)
0.50 (0.020)		 > 85 dB
> 95 dB
GS8000-126 Recommended
Low		 1.40 (0.055)
0.60 (0.024)		 > 75 dB
> 95 dB

1 All measurements made using ARP-1705 modified test method through 3 GHz on 2 mm trace width