• English
  • USD
  • Cart empty
    View Cart
    Shopping cart overview
    Your Cart is currently empty.
  • x

Die attach pastes

Die Attach pastes for Leadframe and Laminate packaging

AVAILABLE DIRECTLY AT CAPLINQ.COM

Die Attach Pastes


Our broad selection of die attach paste formulations provide the reliability and performance today’s leadframe and high-density laminate packages demand. Each package type – from BGAs to LGAs to Smart Cards – has different requirements, which is why we offer a suite of products that cater to the unique needs of those devices. Die attach pastes offer a low modulus for stress reduction and warpage elimination, as well as Bismaleimide (BMI) formulations for low moisture absorption to avoid package cracking during high temperature processing.

Process flexibility and superior performance underscore Henkel’s complete portfolio of die attach pastes for leadframe and laminate devices. Incorporated into applications such as automotive electronics, where temperature control and unfailing function are critical, LOCTITE ABLESTIK die attach pastes deliver high thermal conductivity and high reliability. Robust adhesion to various metal surfaces including palladium, copper, silver, gold and PPF along with proven low-bleed formulas make our die attach materials the products of choice for semiconductor packaging specialists

 

Read More about Die Attach Pastes
Compare Products
41 products
Compare Products
41 products

Product Selector Guide

Electrically conductive die attach paste (DAP) adhesives
Product Description Key attributes Die size Substrate finish Moisture sensitivity level, MSL Volume resistivity (Ohm-cm) Thermal conductivity (W/m-k) Recommended cure
Loctite Ablestik 2000 Ag-filled die attach adhesive - Low bleed
- Low stress
- Ultra-low moisture absorption
- Fast oven cure with no voids
<12X12 Solder mask or Au L2 260°C Capable 5.0X10-4 1.2 30 min. ramp and 15 min. hold at 175°C
Loctite Ablestik 2100A Ag-filled die attach adhesive - Low bleed
- Low stress
- Oven cure
<12X12 Solder mask or Au L2 260 °C Capable 5.0X10-2 1.2 30 min. ramp and 15 min. hold at 175°C
Loctite Ablestik 2300
Ag-filled die attach adhesive - Low bleed
- Low stress
- Excellent dispensability
- Low voiding
- Oven cure
<8x8 Solder mask or Au L2 260 °C Capable 5.0X10-2 0.6 30 min. ramp and 15 min. hold at 175°C
Loctite Ablestik 2700HT Ag-filled die attach adhesive - Excellent bleed performance
- Long work life
- Strong hot/wet adhesion to Au
- Ideal for small needle dispensing
- Oven cure
<8X8 Solder mask, Ag or Au L3 260 °C Capable 3.0X10-5 11.0 30 min. ramp and 30 min. hold at 175°C in nitrogen
Loctite Ablestik ABP 2030SCR
Ag-filled die attach adhesive - Low stress
- Compatible with dam & fill encapsulates
- Excellent dispensing performance for high throughput application
- Snap cure
<8X8 Solder mask, Ag, Au or plastics L3 260 °C Capable 2.0X10-4 2.0 120 sec. at 120°C
Loctite Ablestik ABP 2032S Ag-filled, epoxy die attach adhesive - Good adhesion to a variety of substrates
- Good dispensing
- Low temperature oven cure
<10X10 Solder mask, Ag, Au, steel or plastics L3 260 °C Capable 2.0X10-4 1.0 60 min. at 80°C
Loctite Ablestik 3230
Ag-filled, epoxy die attach adhesive - Low stress
- Excellent adhesion to Cu
- Oven cure
<8X8 Cu or Ag L3 260°C capable 5.0X10 -2 0.6 30 min. ramp and 15 min. hold at 175°C
Loctite Ablestik 3290P Ag-filled, epoxy die attach adhesive - Medium modulus
- Low outgassing
- High reliability
- Snap or oven cure
<5X5 Cu, Ag or PPF L2 260°C capable 2.0X10 -2 0.8 180 sec. to peak 240°C (snap)
Loctite Ablestik 8200TI Ag-filled, die attach adhesive - No bleed
- Excellent adhesion to pre-plated finishes (PPF)
- Oven or snap cure
<5X5 Cu, Ag, PPF or Au L1 260°C capable 5.0X10 -5 3.5 180 sec. to peak 220
°C (snap)
Loctite Ablestik 8290 Ag-filled, epoxy die attach adhesive - Low stress
- Low bleed
- Excellent adhesion to Cu
- Oven cure
<5X5 Cu, Ag, PPF or Au L3 260°C capable 8.0X10 -3 1.6 30 min. ramp and 15 min. hold at 175°C
Loctite Ablestik 8302 Ag-filled, die attach adhesive - Low stress
- Excellent hot/wet adhesion
- Excellent peel strength
- low moisture absorption
- Oven cure
<8X8 Cu, Ag or PPF L1 260°C capable 1.0X10 -4 0.8 30 min. ramp and 60 min. hold at 175°C
Loctite Ablestik 8352L Ag-filled, die attach adhesive - Low stress
- Minimal voiding
- Good bleed performance
- Good adhesion to multiple metal surfaces
- Oven cure or snap
<8X8 Cu, Ag, PPF or Au L2 260°C capable 5.0X10 -5 5.5 120 sec. to peak 220°C (snap)
Loctite Ablestik 8390 Ag-filled, epoxy die attach adhesive - Low stress
- Low condensable volatiles
- Moderately stress absorbing
- Excellent dispensability
- In-line oven snap cure or oven cure
<5X5 Pd or Ag L3 260°C capable 8.0X10 -4 1.8 80 sec. to peak 220°C (snap)
Loctite Ablestik 84-1LMISR4 Ag-filled, epoxy die attach adhesive - Excellent dispense capability
- Long work life
- High throughput
- Box oven cure
<3X3 Ag, PPF or Au L1 260°C capable 2.0X10 -4 2.5 1 hr. at 175°C
Loctite Ablestik 8600 Ag-filled, acrylate die attach adhesive - Low stress
- Excellent in package thermal performance
- Oven or snap cure
<5X5 Cu, Ag, PPF or Au L1 260°C capable 1.0X10 -3 >4 60 sec. to peak 220°C (snap)
Loctite Ablestik ABP 8060T
Ag-filled, BMI hybrid die attach adhesive - High modulus
- High die shear strength
- Hydrophobic
- Oven cure  
<2X2 Cu, Ag, PPF or Au L2 260°C capable 2.5X10 -5 20 45 min. ramp and 60 min. hold at 200°C
Loctite Ablestik ABP 8064T Ag-filled, die attach adhesive - Medium modulus
- Low outgassing
- Oven cure
3X3 to 8X8 Cu, Ag, PPF or Au L1 260°C capable 2.0X10 -5 22 60 min. ramp and 60 min. hold at 180°C
Loctite Ablestik ABP 8065T Ag-filled, epoxy Hybrid die attach adhesive - No channel void issue
- High die shear strength
- Dispensable silver paste
- Oven or snap cure
<2X2 Ag or Au L3 260°C capable 3.0X10 -5 10 30 min. ramp and 60 min. hold at 185
°C in nitrogen (oven)
Loctite Ablestik ABP 8066T Ag-filled, die attach adhesive - Long open time
- High die shear strength
- Hydrophobic
- Low outgassing
- Oven cure
<5X5 Cu, Ag, PPF or Au L1 260°C capable 4.0X10 -5 15 30 min. ramp and 60 min. hold at 175°C
Loctite Ablestik FS 849-TI Ag-filled, die attach adhesive - Excellent in package thermal performance
- Low bleed
- Medium modulus
- Low outgassing
- Oven cure
<8X8 Ag or Au L2 260°C capable 2.0X10 -5 7.8 15 min. ramp and 30 min. hold at 175°C
Loctite Ablestik QMI519 Ag-filled, BMI/acrylate die attach adhesive - Excellent dispense capability
- Long work life
- High throughput
- Hydrophobic
- Fast oven cure or SkipCure
<5X5 Cu, Ag, PPF or Au L1 260°C capable 1.0X10 -4 3.8 >10 sec. at 200°C (SkipCure)
Loctite Ablestik QMI529HT-LV Ag-filled, BMI hybrid die attach adhesive - Good dispensing characteristics
- Stable at high temperatures
- Hydrophobic
- Excellent adhesive strength
- Oven cure
<8X8 Ag or PPF L2 260°C capable 5.0X10 -5 8 30 min. ramp and 60 min. hold at 175°C
Loctite Ablestik SSP 2020 Ag sintering die attach adhesive - High die shear strength
- Robust dispense and stencil print performance
- Good workability
- High temperature sinter with or without pressure
<3X3 Ag or Au L3 260°C capable 4.8X10 -5 >100 10 min. ramp and 60 min. hold at 250°C (pressureless sintering)
Electrically Non-Conductive Die Attach Paste (DAP) Adhesives
Product Description Key attributes
Die size (mm) Substrate finish Moisture sensitivity level, MSL Modulus at 25°C (MPa) Thermal conductivity (W/m-k) Recommended cure
Loctite Ablestik 2025D Silica-filled, die attach adhesive - Low bleed
- Very low stress
- Red color for vision recognition
- Oven cure
<8X8 Cu, Ag or Au L3 260°C capable 407 0.4 30 min. ramp and 15 min. hold at 175°C
Loctite Ablestik 8900NCM PTFE-filled, epoxy die attach adhesive - Low bleed
- Low voiding
- Moderately stress absorbing
- Excellent dispense capability
- Contains no category 3 carcinogenic, mutagenic or reprotoxic (CMR) substances
- Oven cure
<8X8 Pd, Cu, Ag or PPF L3 260°C capable 680 0.3 30 min. ramp and 15 min. hold at 175°C
Loctite Ablestik ABP 8611 BMI Hybrid die attach adhesive - Excellent dielectric properties
- Suitable for Cu wire or Au wire bonding
- High modulus at high temperatures
- Oven cure
<2X2 Cu, Ag or PPF L3 260°C capable 5,000 0.7 30 min. ramp and 60 min. hold at 175
°C
Loctite Ablestik ABP 8910T Alumina-filled, BMI hybrid die attach adhesive - Medium modulus
- High reliability
- Oven cure
<8X8 Cu, Ag or PPF L3 260°C capable 8,870 3.1 30 min. ramp and 15 min. hold at 175°C
Loctite Ablestik QMI536NB PTFE-filled BMI die attach adhesive - Low bleed
- Very low stress
- White color for vision recognition
- Widely used for stacked die
- Fast oven cure
<8X8 Cu, Ag or PPF L3 260°C capable 300 0.3 30 min. ramp 150°C

Frequently Asked Questions

What is the difference between thermoplastic and thermoset die attach?

Thermoset materials


The original die attach polymers were thermoset polymers and are still the most widely used today. After polymerization, these adhesives exhibit a rigid three-dimensional structure, a consequence of chemical bonds between adjacent chains (cross-linking). When heat is applied, these interlinked chains cannot move freely, hence their phase changes are not reversible.

The amount of interlinking between chains depends on the chemistry of thermoset polymers. High cross-linking means a hard, rigid and often brittle material, while low cross-linking means the material is more pliable and can be softened (they do not lose their original shape) by heating to high temperatures. Thermosets are commonly used in circuit board and semiconductor/device packaging for low to medium power applications. A disadvantage of thermosets is that sometimes, precise repeatability of the polymerization step can be difficult.

Thermoplastic die attach materials


Thermoplastics were formulated to overcome the negative qualities of thermoset polymers. After polymerization, they are linear in structure. The manufacturer polymerizes the adhesive fully under controlled temperatures, reaction rates, times, and pressures. This ensures repeatable die attach properties.

Their linear structure allows them to be re-melted because their long polymer chains slide past one another on heating. Cooling the adhesive returns it to the solid state. As a die attach, a thermoplastic need not be fluid for effective bonding, the viscosity that allows the plastic to flow into the microstructure when pressure is applied should serve as a guide. The need for pressure also means additional equipment is required compared to thermosets. They are instrumental in circuit board device and packaging.


Learn More

Conductive die attach pastes

 

Conductive die attach pastes find the most significant application, about 80% of the die attach market, in attaching chips to leadframes where their electrical conductivity is an important parameter. These pastes are made of organic resins mixed with inorganic fillers. The resins could be thermosetting such as epoxy, phenolics, cyanate esters, and silicone or thermoplastics such as polyimides, and polyurethanes. Metal fillers such as silver, copper, gold, nickel, palladium have been used.

The resin is responsible for the mechanical properties of the adhesive, and the fillers are responsible for its electrical and thermal conductivity. Conductive die attach pastes form electrical connections between leadframes, I/O leads, active and passive devices, and other circuit components. They also act as channels that facilitate electrostatic dissipation and electrical grounding. 

 

Based on their electrical conductivity, conductive die attach pastes can be classified as:

  • Isotropic conductive adhesives (ICAs), popular for surface mount technology. They conduct electricity in all directions equally.
  • Anisotropic conductive adhesives (ACA) used for adhering IC chips to glass panels in LCDs and in tape automated bonding packages. They conduct electricity in the Z-axis only. 
  • Non-conductive adhesives (NCAs) are useful in applications where the mechanical bond from the die attach is more important than its electrical conductivity.

A consequence of chips and devices becoming smaller is that they are susceptible to high temperatures experienced during electrical transmission. Without sufficient heat dissipation from a die attach material to appropriate heat sinks in a circuit, destruction and failure of parts become inevitable. Thermal conductivity is, therefore, a critical parameter affecting performance. For a paste to qualify as electrically conductive, its minimum thermal conductivity as specified by Method 5011 of the MILD-STD-883 standard is 1.5 W/m·K.



Properties of conductive die attach pastes affecting their performance

Numerous conductive die attach pastes are available in the market, each with its unique differentiating property. The essential properties to consider that have far-reaching effects on the performance of any given product are: filler composition, morphology, manufacturing, and processing requirements.

 

Type of filler and thermal conductivity

The majority of polymer resin used in formulating conductive die attach are insulators by nature, so fillers are incorporated to increase their electrical and thermal conductivity. Fillers that have been used commercially are silver (429 W/m·K), copper (401 W/m·K), gold (318 W/m·K), and nickel (90-92 W/m·K). Their thermal conductivity values indicate why silver is so popular. 

Understandably, silver-filled die attach pastes are expensive. However, silver exhibits other superior qualities including the fact that silver oxide is stable and conductive. On the other hand, copper-filled variants experience a decrease in conductivity with oxide growth after exposure to high temperatures. Nickel has a low oxidation rate, and given its lower thermal conductivity value, is a preferred filler in low-cost anisotropic adhesives. 

Even though the thermal conductivity values of the filler metals are substantial, those of the formulated pastes are considerably lower. A value such as 1.9 W/m·K is not unusual for commercially available silver-filled pastes, while others as high as 7-11 W/m·K are also available. 

 

Percentage of filler

The filler percentage of a composite mixture is important because of the underlying trade-offs. A large amount of metal is necessary for greater conduction, but this affects physical properties like elasticity and mechanical strength. 

According to percolation theory, a critical filler concentration exists where the 3-D network structure is established, and the increase in conductivity becomes significant by several orders of magnitude. Beyond this concentration, conductivity does not increase as noticeably with an increase in filler composition. Therefore, only a minimum quantity of filler is required to achieve a degree of electrical performance that is inherent to the composite. Typical values for ICAs lie between 25-30 vol % and 5-10 vol % for ACAs. 

 

Filler Morphology

The characteristics of the filler material such as size, shape, orientation, and distribution in the mixture affect the viscosity/rheology of the formulation. These properties come into play in the bond line thickness. Since thin bond lines enhance thermal conductivity, fine particle sizes are preferable and it’s why metal powders with diameter sizes between 5-20 µm are typical. 

 

Tensile modulus and CTE

More than connecting materials together, adhesives act as load distributors. Assembled packages having different CTEs need a low modulus adhesive to compensate for the mismatch. Increasing the filler loading for the sake of high conductivity increases the tensile modulus of a die attach paste but decreases the ultimate strength. This could result in cracking during thermal cycling or vibration. Manufacturers use plasticizers to lower the modulus and add flexibility.

 

Processing requirements

Parameters like temperature, cure time, pressure, storage conditions, and shelf life, impact not only the strength and reliability of a die bond, but also design and manufacturing decisions. 

 

  1. Manufacturing

In addition to the resin and filler, other components like hardeners, thinners and curing agents are added to modify cure rates, viscosity, and other mixtures properties. The die attach paste can be supplied as a single component where the catalyst is latent (usually by storing below -40°C ) until exposed to the given cure temperature. Supplied as two components, you get a separate resin, called part A, and the catalyst, part B. Either or both part A and B may contain the metal filler. The parts are weighed, mixed, degassed and cured. Cost-cutting objectives favor formulations that are solvent-free and have shorter cure cycles.

 

  1. Curing

Curing involves the polymerization of the resins to solidify them into strong adhesive joints. Curing agents and sufficient heat (oven, UV) are often required for the reaction to occur and the type of catalyst will influence the cure time and temperature. 

Typical pastes cure anywhere between 80°C to 180°C and some two-component die attach can cure at room temperature. Snap cure (often one-component) pastes derived from modified cyanate esters can cure in under 1-2 minutes making them an excellent choice for high volume manufacturing.  

 

  1. Storage 

One-component formulations often need to be stored in a freezer, and this reduces the ease of using it. If stored incorrectly, adhesives can polymerize prematurely, absorb moisture, or crystallize. Also, if left too long before dispensing at room temperature, an adhesive mixture can separate leading to die bond inconsistencies where some parts are resin-rich and will flow excessively, while other parts are filler-rich and don’t flow easily. Die attach formulations based on bismaleimide resins were developed to counteract the tendency to absorb moisture.

 

  1. Dispensing

Conductive (and non-conductive) die attach pastes may be syringe dispensed or stencil printed depending on the viscosity of the mixture.

 

Applications of conductive die attach pastes

  • Leadframe packaging for suitable attachment to surfaces like copper, gold, silver, palladium, PPF
  • Wirebond IC packaging for BGAs, PBGAs
  • Printable chip on board devices, flexible circuit boards

 


Non-conductive die attach pastes  

 

Except for the difference in their composition and application, non-conductive die attach pastes are not far off from their conductive cousins. They are made of organic resins like epoxy, polyimides, silicones, acrylates and non-conductive fillers that could be metal, metal oxides, metal nitrides and more. Examples of ceramic and inorganic fillers are silica (SiO2), alumina (Al2O3), and beryllium oxide (BeO). An organic filler like PTFE has also been used successfully.

These pastes find the most use in die attach for semiconductors and surface mount devices, where a strong adhesion that can withstand physical and thermal stresses combined with strong electrical insulation is the priority. Example applications are automotives, sensors, consumer electronics, memory cards, RFID cards, USBs and LEDs. 

There are applications where pastes with low thermal and electrical conductivity are sufficient. There are other situations, however, where pastes need high thermal conductivity because temperature control is critical. This second category are thermally conductive and electrically insulating die attach pastes. Unfilled polymer resins are natural thermal insulators (0.1–0.5 W/m·K), and the added fillers increase thermal conductivity tenfold or better. Method 5011 of MIL-STD-883 standard specifies the minimum thermal conductivity for electrically insulative die attach as 0.15 W/m·K. 

 

Properties of non-conductive die attach pastes affecting their performance

 

Thermal conductivity and heat dissipation

The thermal conductivity of silver-filled die attach pastes makes it excellent for heat dissipation, but in electronic applications where a high thermal conductivity must be combined with low electrical conductivity, ceramic fillers such as alumina and silica are good alternatives. Examples are packaging materials for power semiconductor devices where the heat generated needs to be dissipated to ensure its long life and reliability.

Thermal dissipation through the die attach occurs mainly through conduction and convection. Therefore, the morphology of the filler materials, their shapes, sizes and their distribution in the resin influence the process. Smooth ceramic powders less than 20 µm in diameter are typical. 

 

Thermal conductivity and type of non-conductive filler

The thermal conductivity of diamond is impressive, as high as 1500-2000 W/m·K depending on its purity, and that of diamond-filled pastes can exceed 12 W/m·K. However, the price of diamond is prohibitive for everyday applications. Fillers that have found commercial use are alumina (99%, 40 W/m·K), aluminum nitride (170-260 W/m·K), boron nitride (130-260 W/m·K), and silicon carbide (270 W/m·K). 

 

Percentage of filler and flow properties

Boron nitride at a loading level of 40 wt% can produce a mixture with a bulk thermal conductivity of 8-10 W/m·K, although the thixotropic end result can be difficult to dispense. On the other hand, alumina is low cost and a popular choice due to its more manageable flow properties. When mixed with organic resin, the resulting paste has a thermal conductivity of 1.5 W/m·K at a loading level of 75 wt%. 

Therefore, although the thermal conductivity of a paste may be increased by adding more filler as far as the density of the resin will allow (typically, 85%–90% by weight and 40%–50% by volume), there is a point where doing so is no longer beneficial, negatively impacting other properties of the paste, e.g., viscosity. To counter this, thixotropic additives are introduced to improve flow properties. You will find that many commercially available die attach pastes are formulated using similar core resins, fillers, and catalysts but differ in the quantities of these ingredients.

Another factor affecting the thermal conductivity of a paste other than type and percentage of filler is the curing requirement of the paste.

 

Electrical insulation 

Non-conductive die attach pastes are required when it’s essential to inhibit the flow of electricity (avoid electrical interference/ isolate electric current). In order to understand how non-conductive die attach pastes compare in fulfilling these needs and requirements, it will be helpful to define a few parameters you will come across in data sheets:

 

  1. Dielectric constant: a dimensionless ratio that measures the ability of a material to store electrical energy when exposed to an electric field. The dielectric constant for non-conductive die attach pastes used for electrical insulation will typically lie between 2-5. A higher value in the range 6-12 is acceptable where some electrical conductivity can be overlooked.

 

  1. Dissipation factor: measures the power loss in a material experiencing an alternating electric field, a ratio of the power dissipated to the power applied. A low value implies the die attach paste, the substrates to which it adheres, and the surrounding circuit components will experience only low levels of heating. At ambient temperatures, typical DF values lie between 0.003 to 0.030 at 1 KHz, and can go up to 0.050 at 1 MHz. 

 

  1. Dielectric strength: measures the maximum voltage that, when applied across a material, won’t cause dielectric breakdown. Beyond this point (breakdown voltage), a non-conductive die attach paste becomes electrically conductive. Also, dielectric strength decreases as temperature or frequency increases.

 

Mechanical strength and coefficient of thermal expansion

The resin part of the paste is responsible for providing shear and tensile strength to the adhesion throughout all the possible conditions an assembly will encounter. Apart from thermal conductivity and flow properties, the type of filler used influences the CTE of the paste which is critical when bonding dissimilar materials together. Unfortunately, while these fillers may improve the CTE, their addition negatively impacts the bond strength. It becomes a trade-off decision about what the percentage of filler loading should be for an application.

 

Processing and dispensing

Non-conductive pastes may be based on thermoset or thermoplastic resins. The paste can be supplied as a single component with a latent catalyst/ hardener or a two-component mixture, requiring expert weighing, mixing and degassing of the resulting composite.

Die attach pastes (conductive and non-conductive) can be deposited into any shape through syringe dispensing or stencil printing, making them ideal, where the components to be bonded, have interesting geometries. They can also be scaled for mass manufacturing and automation using high-end equipment that is optimized for all the critical parameters to avoid common defects such as voiding and bond thickness variation. 


Application

  • Leadframe packaging for proper attachment to surfaces like copper, gold, silver, palladium, PPF
  • Laminate packaging in BGAs, LGAs
  • Printable board on chip for DRAM devices, flexible circuit boards
  • For bonding high power LEDs and surface mounted devices, SMDs to PCBs
  • For bonding ICs to heat sinks