ASM_catalogue_ASM_Stencils_from_the_global_No_1_EN_210419.pdf - 第12页

NEW : DEK Electroform Mini LED Stencil Miniaturization trend demands stencil with smaller apertures. In recent years, miniLED has emerged as a new segment with high growth potential and has drawn the interest of most maj…

Electroform stencils can be produced with modications to

accommodate specic applications. One such adaptation is a

technique called Variable Aperture Height Technology (VAHT),

whereby a gasket overgrowth is created around apertures to

create more aperture height to allow for increased paste volumes

to be deposited.

VAHT is ideal for PCBs that incorporate both small and large

components that require varying amounts of solder material.

Aperture gasket height can be 1 to 2 mils higher than the base

stencil thickness.

DEK Electroform Variable Aperture

Height Technology (VAHT)

DEK VAHT technology offers a unique alternative to multi-level stencils for non-

homogeneous assemblies that call for larger, area-specific paste volumes to

accommodate bigger components.

Benets:

■ Ideal for heterogeneous assemblies, allowing printing of

various solder paste volumes with a single stencil

■ Improved throughput

NEW: DEK Electroform

Mini LED Stencil

Miniaturization trend demands stencil with smaller apertures.

In recent years, miniLED has emerged as a new segment with

high growth potential and has drawn the interest of most major

LED companies. miniLED are used in the back-light units (BLUs)

of display screens and are very competitive both in terms of cost

and function, oering excellent contrast though the use of local

dimming. However, miniLED products pose a real problem to

the packaging industry which has not yet developed solutions

for handling such small dies with the accuracy and throughput

required; a typical miniLED die is smaller than an 0201m

component.

The challenges related to stencil printing for miniLED products

involve printing paste deposits which are smaller than 100µm

in size and controlling the uniformity of the paste deposits to

avoid die tilt, bridging and other defects. Electroform is uniquely

positioned to address these challenges. Electroformed stencils

have better paste release capabilities, a result of the superior

smoothness of the aperture side wall and the surface energy of

nickel.

In addition, miniLED products using RGB congurations typically

require more than 100,000 apertures in one stencil as well as a

stencil thickness in the range of 23 – 40 µm. Laser cut stencils

are not able to meet such requirements.

Specications:

■ Aperture Size: 40 µm × 40 µm (minimum), ± 5 µm

■ Thickness: 23 µm (minimum)

■ Gap between apertures: 50 µm (maximum)

■ Frame Size: DEK VectorGuard

23” × 23”

■ Positional Accuracy: 0.1 µm/mm

Process Support Products

ASM: Stencils from the global No. 1

DEK PumpPrint™ /

Adhesive stencils

DEK PumpPrint

technology enables a wide range of adhesive patterns to

be successfully deposited using a screen printing platform.

DEK PumpPrint

/ Adhesive stencils enable deposition of

adhesives in a single stroke, as opposed to the slower, serial

process of dot dispensing systems. With adhesive printing,

throughput is dramatically increased and cycle time is constant.

Also eective for certain solder applications, DEK PumpPrint

stencils can be utilized for solder deposition around through-hole

component leads or into the base of deep packages.

DEK PumpPrint

/ Adhesive stencils are constructed of an

acrylic material and available in standard thicknesses of 1.0

mm to 3.0 mm, or up to 8 mm for special applications. Printing

through accurately machined apertures, deposit heights from

75 µm to 1 mm can be achieved. Specially designed DEK

PumpPrint

stencils are also available for use with the DEK

VectorGuard

Classic stencil frame system.

Features and benets:

■ Significantly improved throughput, efficiency, and flexibility

compared to traditional adhesive dispensing

■ Nozzle changeovers eliminated

■ Allows re-deployment of existing resources

■ Underside routing clears components, cut and clinched

through-hole leads, paste and solder mask

■ Stencils are lightweight and solvent-resistant

■ Available for the DEK VectorGuard

Classic stencil frame

system