803774 Bergquist, 803774 Datasheet - Page 12

• Manufacturer Part Number: 803774
• Description: BOARD LED IMS SEOUL SEMI P5
• Manufacturer: Bergquist
• Series: Thermal Clad® IMS®r
• Type: Thermal Clad Boardr

Specifications of 803774

• Shape: Star
• For Use With/related Products: Seoul Semiconductor Z-Power P5
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant

10
Using Thermal Clad Dielectric Material...
Two-Layer Systems Using FR-4 Circuits
Or Thermal Clad Circuits
Bergquist dielectrics are ideal for applications requiring a two-layer
solution.Two-layer constructions can provide shielding protection and
additional electrical interconnects for higher component density.
Bergquist dielectrics will provide superior thermal performance over
traditional FR-4 constructions. In addition, thermal vias can maximize
thermal capabilities for applications utilizing power components.
When vias can not be used, selecting higher performance dielectrics
can solve thermal issues independently (see graph, below).
DBC Replacement
Replace Ceramic Substrates
Thermal Clad can replace large-area ceramic substrates. It can also be
used as a mechanically durable support for ceramic circuits or direct-
bond copper subassemblies.The copper circuit layer of Thermal Clad
has more current carrying capability than thick-film ceramic technology.
Thermal Clad has replaced ceramics and DBC in applications due to mechanical robust-
ness and its ability to be fabricated in a wide variety of form-factors.
The graph depicts the modeled thermal result of various two-layer constructions as a func-
tion of device case temperature. The emphasis is the thermal effect of proper vias utilization.
FR-4
FR-4
HT
HT
HT
Direct Die Application
Direct die attach and wirebond are increasingly popular methods of
component mounting to Thermal Clad substrates. A key benefit to this
structure is lower thermal resistance as compared to conventional sur-
face mount component packages soldered to an IMS substrate.
When designing circuits using Chip-On-Board (COB) technology it is
important to use the appropriate surface finish to achieve excellent
die mounting and wire bond connections. The die attachment is
accomplished using SnPb, Pb-free solders, eutectic gold/in solder or an
electrical/thermal conductive adhesive, depending on the application
requirements to adhere the die to the substrate.The wirebonding per-
formed to make circuit connections is usually either gold or aluminum.
ENEPIG (Electroless Nickel/Electroless Palladium/Immersion Gold) is
recommended for gold wire and ENIG (Electroless Nickel/ Immersion
Gold) for aluminum wire applications. HT dielectrics are U.L. solder
rated at 325°C/60 seconds, enabling Eutectic Gold/Tin solders.
Heavy Copper
Applications requiring heavy copper for high current or heat
spreading are not limited to single-layer needs. The ability to have
internal layers of heavy copper can provide greater application
flexibility. Direct access to the internal copper layer to directly attach
or mount components provides unique applications capability.
Look for opportunities to reduce the copper thickness. In many appli-
cations, Bergquist T-Clad thermal performance reduces the need for
heavy copper.
Close-up view of direct die
attachment in an LED
application. The Thermal
Clad substrate is used to
mount the die or module.
Bergquist has the ability to
laminate heavy copper up to
5 oz. (175µm) on the internal
layer utilizing a thicker deposit
of HT dielectric.