RF-35A2
is designed with an ultra low
berglass content to achieve
“best in class” insertion loss properties and a homogeneous
dielectric constant throughout the laminate.
e uniform dispersion of ceramic throughout the laminate
yields extremely low x and y coecients of thermal
expansion. e low modulus and low x-y CTE values make
RF-35A2 an attractive material for the surface mounting of
chip carriers.
RF-35A2 is manufactured in a proprietary multi-step
process that provides excellent dielectric properties along
with superior copper peel adhesion.
e low 0.0016 dissipation factor at 1.9 GHz allows for
maximum power transfer resulting in low heat generation.
Benets & Applications:
• Low loss properties
• Dk tolerance of +/- 0.05
• Homogeneous Dk
• Excellent peel strength
• Low moisture absorption
• Ease of drilling
• Power ampliers
• Filters/couplers
• High speed digital
• Multilayer
• Passive components
• Wireless antennas
North & South America
Taconic - Headquarters
Petersburgh, NY 12138
Tel: 518-658-3202 / 1-800-833-1805
addinfo@4taconic.com
Europe/Middle East/Australia
Taconic International Ltd.
Republic of Ireland
Tel: +353-44-9395600
add@4taconic.com
Asia
Korea Taconic Company
Republic of Korea
Tel: +82-31-704-1858
sales@taconic.co.kr
China
Taconic Advanced Material (Suzhou) Co., Ltd.
Suzhou City, China
Tel: +86-512-6286-7170
tssales@taconic.co.kr
Taconic is a world leader in RF laminates and high speed
digital materials, oering a wide range of high frequency
laminates and prepregs. ese advanced materials are used
in the fabrication
of antennas,
multilayer RF
and high speed
digital boards,
interconnections
and devices.
Cross-section of RF-35A2 construction
An ISO 9001 Registered Company
www.taconic-add.com
Commercial and Government Entity (CAGE) Code: 1C6Q9
RF-35A2 Ultra Low Loss Power Amplifier Substrate
PTFE Composites vs. Rubber (Hydrocarbon) Composites:
A
primary dierence between PTFE-based composites and rubber based (hydrocarbon) substrates is
PTFE is oxidation resistant. PTFE starts to degrade near 600 °C when the carbon-uorine bond starts
to fail. PTFE is a thermoplastic and does not have unreactive chemistry aer processing. Rubbers, however,
cure by a thermosetting mechanism and never cure to completion, thus leaving some level of unreacted
chemistry. Rubber substrates are not temperature stable or oxidation resistant which causes these materials
to turn yellow and then black with air/heat. Automotive rubber is typically sulfur cured and contains a high
level of carbon black. ese additives cannot be used in laminates due to their poor electrical properties.
Laminate suppliers cannot use the same strategies as the automotive industry to stabilize their rubber.
is leaves the rubber (hydrocarbon) products susceptible to temperature driven oxidation (a time and
temperature-based phenomenon). Oxidation, diusion, stress relaxation and any process that is temperature
related generally follows an Arrhenius relationship where the rate of oxidation doubles with every ten degree
rise. Rubber oxidation is no exception; with exposure to temperature and air, rubbers oxidize, embrittle and
their elongation and peel strengths decrease while their dielectric constants and dissipation factors increase.
PTFE-fiberglass products such as RF-
35A2 do not suer from a change in their
dielectric constant or dissipation factor
with temperature exposure. Figures 1 and 2
show the change in dielectric constant and
dissipation factor of a non-brominated rubber
(Hydrocarbon) and PTFE ceramic fiberglass
laminates (TLF-35, RF-35 and RF-35A2) with
exposure to air at 195 °C. Figure 3 shows
similar trends for peel strength. Copper peel
strength will decline with temperature due
to the oxidation of the copper in addition to
any factors that would cause embrittlement
of the resin system. This oxidation (yellowing)
will occur at as low as 95 °C over prolonged
time periods.
Df
Figure 1 Figure 2
Figure 3
Peel Strength (lbs./inch)
Dk
C o p p e r P e e l S tr e n g t h D e g r a d a tio n (h o ld @ 1 5 0 C )
3
3.5
4
4.5
5
5.5
6
6.5
7
0 10 20 30 40 50 60
D a y s
Peel Strength (lbs/in)
PTFE �� ceramic - fiberglass
Brominated rubber (hydrocarbon)
Non Brominated
Rubber (hydrocarbon)
Dk Changes According to Aging Time (1,000 hrs.)
Copper Peel Strength Degradation (hold @ 150°C)
Days
0 200 400 600 800 1000
3.40
3.45
3.50
3.55
3.60
3.65
TLF-35 DK
Hydro Carbon
RF-35 DK
RF-35A2 DK
DK
HOURS
0 200 400 600 800 1000
0.000
0.001
0.002
0.003
0.004
0.005
0.006
TLF-35 DF
Hydro Carbon DF
RF-35 DF
RF-35A2 DF
Df
HOURS
Df Changes According to Aging Time (1,000 hrs.)
RF-35A2 Ultra Low Loss Power Amplifier Substrate