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Electrically & Thermally Conductive

Epoxy Technology offers a full range of electrically and thermally conductive epoxy adhesives for the semiconductor, optoelectronic, automotive, aerospace and electronic assembly industries. Our extensive product line allows users to easily select the optimal adhesive for their specific application; based on the bescombination of physical, electrical and mechanical characteristics.

EPO-TEK electrically conductive epoxies have been used successfully for over 35 years in a wide variety of applications including: IC packaging, hybrid microelectronics and circuit assembly as well as today in solar cell assembly, LEDs and high power management.

Representative examples :

• Epo-Tek® H20E is a two components, 100% solid silver-filled epoxy system designed specifically for chip bonding in microelectronic and optoelectronic applications.  It is also used extensively for thermal management applications due to its high thermal conductivity.  It has proven itself to be extremely reliable over many years of service and is still the conductive adhesive of choice for new applications.  It is also available in a single components frozen syringe.Epoxy Technology’s Epo-Tek® H20E has been used successfully for over 35 years in a wide variety of applications including LED, solar, high power management and HDD applications.
• EPO-TEK® EK1000 – a new generation, single component ECA with exceptional thermal conductivity for high power applications with a thermal conductivity value ranging from 12.6 to 22.0 W/m°K.
• EPO-TEK® EJ2189 – a new generation, two component ECA designed for low temperature curing from 23°C (ambient) to 80°C that exhibits superior adhesion to a wide variety of substrates including most metals, ceramics, glass and plastics.
• EPO-TEK®E2101 is a two component, thixotropic, electrically conductive adhesive.  It may be used for circuit assembly and semiconductor applications.
• EPO-TEK® E3001-HV is a snap cure, single component, silver-filled die attach adhesive for semiconductor plastic IC packaging.  It is also available in a frozen syringe.
• EPO-TEK®E3082 is a single component, silver filled, electrically and thermally conductive adhesive for semiconductor die attach, hybrid, electronics and optical applications. It is a one component version of EPO-TEK®E2082.
• EPO-TEK®E4110 is an electrically conductive, silver-filled epoxy paste.  This two component system is designed for low temperature curing from ambient to 80°C, although other heat cures can be used.
• EPO-TEK®ED 1003 is a single component, electrically conductive adhesive designed for high power LED die attach applications.  Its combination of high thermal conductivity, shiny silver appearance and low outgassing are ideal for the demanding requirements of high brightness LED’s.  Other features include a long potlife, low viscosity and high thixotropic index making it suitable for a wide range of application methods wafer level stamping and syringe dispensing.
• EPO-TEK®ED1021 is a single component, silver-filled epoxy designed for low power semiconductor LED die attach applications.  Unique features include its ability to achieve high thermal conductivity values at low cure temperatures and a very shiny silver appearance which enhances overall LED brightness.   Other benefits include long pot-life, low viscosity and high thixotropymakng it ideal for wafer level tamping as well as syringe dispensing.
• EPO-TEK® EJ2189-LV is a low viscosity, two-component, room temperature curing conductive epoxy.
• Epo-Tek® EK 1000 is a single components, silver-filled adhesive that exhibits exceptional thermal and electrical conductivity along with a shiny silver appearance making it ideal for the demanding requirements of high power LED die attach applications.  Other benefits include low viscosity and high thixotropy making it suitable for a wide range of application techniques.
• EPO-TEK®EM127 is a single component, heat curable, electrically conductive epoxy adhesive for semiconductor IC and LED die attach applications.
• EPO-TEK®H20E-PFC is a two component, semiconductor grade epoxy, designed for flip chip interconnects using a solder-free joining method.
• EPO-TEK® H20S is a modified version of EPO-TEK®H20E, designed primarily for die stamping and dispensing techniques for chip bonding.  EPO-TEK®H20S is a highly reliable, two component, silver-filled epoxy with a smooth, thixotropic consistency.  In addition to the high electrical conductivity, the short curing cycles, the proven reliability, and the convenient mix ratio, EPO-TEK® H20S is extremely simple to use.
• EPO-TEK®H31 is a single component, silver-filled, electrically conductive epoxy designed for semiconductor die attach applications found in hybrids, JEDEC, and opto-electronic packaging.
• EPO-TEK®H35-175MP  is a single component, silver-filled epoxy for military hybrid die and component attach.
• EPO-TEK®H37-MP  is a single component, electrically conductive, thixotropic silver-filled adhesive for die-attach and SMD attach inside hybrid microelectronic packages. It is also available in a frozen syringe.

Optical / Fiber Optic

Epoxy Technology’s optical line of adhesives is used for bonding and protective coatings in various fiber optic applications. Our epoxy adhesives are frequently used to bundle optical fibers and bond components in optoelectronic devices such as: telecommunication networks, aircraft, satellites as well as medical and scientific instruments.

Representative examples:

Thermal Conductive / Electric Insulating

Epoxy Technology’s thermally conductive line of epoxies are used extensively in many high-tech electronic applications. EPO-TEK products are unparalleled in their performance in effectively removing heat, providing increased dielectric strength and protecting circuits from hostile environments. Our epoxy adhesive properties can range from rigid (providing robust, thermally enhanced circuit protection) to flexible (ideal for substrates with significant CTE mismatches).

 Representative examples :

Low Outgassing Adhesives

What Is Outgassing?

Outgassing is a measure of the level of residual low molecular weight species (including water if the material is not conditioned in a low moisture environment prior to testing) that can be evolved at elevated temperatures.

How Is It Measured?

One method for measuring levels of outgassing is Thermal Gravimetric Analysis or TGA. This technique measures very small weight changes in a material as a function of temperature. The resultant percent weight versus temperature curve is then used to determine the weight loss or outgassing at specific temperatures.
Below is an example of a typical weight loss vs. temperature scan.

What Are The Standards?

NASA ASTM E595

Products that meet the NASA outgassing requirements must exhibit less than 1.0% Total Mass Loss (TML) after being exposed to 125°C for 24 hours in a vacuum. They must also contribute less than 0.1% Collected Volatile Condensable Materials (CVCM) during this exposure.

MIL-STD 883/5011

For military applications, products must produce 1.0% or less outgassing when exposed to 200°C in order to pass MIL-STD 883 Method 5011. Epoxy Technology is an approved DSCC testing facility for this standard.

Telcordia GR-1221

The fiber optic industry goes by many names including: photonics, telecommunications or optical components. There are many testing requirements within this industry. Epoxy Technology adhesives have been tested in accordance with Telcordia (formerly Bellcore) Standard GR-1221, “Generic Reliability Assurance Requirement for Passive Optical Components”. This testing helps to assure the practical, useful life for certain manufactured devices relating to long term (25 year) performance. For this test, the cured adhesive is heated from 50°C to 150°C at 5°C/minute in the TGA. A 0.1% weight loss for heat cured systems and a 0.25% weight loss for UV cured systems is considered evidence of a properly cured system and meets the test requirements. Below is a listing of EPO-TEK products that have met or exceeded this standard.

Epoxies – Useful info

Single Component Epoxies

Single component epoxies that cure at low temperatures (below 50 degrees C) need to be delivered frozen. These are usually shipped in specially insulated cartons containing « dry ice ». N.B. Most of our two component epoxies can be delivered in ready-to-use syringes.

Moisture inhibits Curing

Water inhibits the curing reaction of all epoxies. This means that humidity present in the air could cause an epoxy to cure more slowly than normal or prevent complete curing. In most cases, humidity in the air doesn’t have any measurable effect. So how does humidity cause problems?
1) If the epoxy is colder than the air temperature, water vapor will condense onto it.
2) If the epoxy is applied as a very thin layer, the surface area-to-volume ratio becomes so great that a significant amount of water can be adsorbed onto its surface.
3) Epoxy hardeners (part B) are hydrophilic. Therefore the container should never be left open for longer than necessary.

The Mix Ratio

The mix ratio defines the proportion of epoxy resin (part A) that should be mixed with the hardener (part B). In most cases, it is best to measure the parts by weight. A mix ratio of 10:1 means 10g part A + 1g part B.
N.B. Although the mix ratio is not critical, variations will result in slightly different end-products. Whereas a mixture containing an excess of part A will still cure, a mixture with an excess of part B may remain soft and appear not to cure! This is actually due to the presence of unreacted part B which acts as a « plasticizer ».

Room Temperature Curing Epoxies

While many Epoxies cure at room temperature, a heat cure step is recommended to achieve optimum properties.

Low Outgassing

See the complete brochure concerning Low Outgassing.