CLA-2 CO:R:C:G 084659 AJS
TARIFF NO: 8541.29.00; 8542.20.00
Mr. Donald Alford Weadon, Jr.
Attorney-at-Law
Weadon, Rehm, Thomsen & Scott
Suite 500
1301 Pennsylvania Avenue, N.W.
Washington, D.C. 20004
RE: Transistor modules from Japan
Dear Mr. Weadon:
Your letter of April 25, 1989, on behalf of Toshiba America
Electronics Components Inc., requesting a tariff classification
under the Harmonized Tariff Schedule of the United States
Annotated (HTSUSA) has been referred to this office for reply.
FACTS:
The articles in question are three types of transistor
modules to be imported from Japan. The first is the Bipolar
Darlington Transistor Module (BDTM). The BDTM is a multi-
terminal device consisting of single or multiple transistor diode
parts {directly mounted on a direct bond copper circuit board
(DBCCB)} capable of amplification, oscillation, frequency, or
switching of electrical currents, behaving essentially as a
single transistor device with a high current and power rating.
Variation in resistivity between two of the terminals results
from the application of an electrical field or control signal to
a third terminal, whose transistor action depends on both
positive and negative charge carriers.
The second is the Metal Oxide Semiconductor Field Effect
Transistor (MOS-FET). The MOS-FET is a unipolar, voltage-
controlled device consisting of single or multiple transistor
diode parts (directly mounted on a DBCCB) whose output depends on
the induced depletion or enhancement of charge carriers between
at least two terminals. Its output current can be controlled
using very low gate drive power levels. It can be maintained in
an "on" or "off" state with essentially no input gate power,
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requiring only relatively small gate pulse currents to charge and
discharge its input gate capacities during switching.
The third is the Insulated Gate Bipolar Transistor Module
(IGBT) which combines both bipolar and power MOS-FET
technologies, (likewise consisting of single or multiple
transistor diode parts directly mounted on a DBCCB) rendering
high input impedance as well as high forward conduction current
density. Containing two back-to-back high voltage junctions, it
is capable of symmetrical forward and reverse blocking capacity.
ISSUE:
Whether the articles in question are properly classifiable
in subheading 8541.29.00, HTSUSA, which provides for other
transistors; or in subheading 8542.20.00, HTSUSA, which provides
for hybrid integrated circuits.
LAW & ANALYSIS:
Chapter 85, note 5 (a), HTSUSA, states transistors are semi-
conductor devices, "the operation of which depends on variations
in resistivity on the application of an electric field." The
Explanatory Notes, for heading 8541 at (A)(II) describe
transistors as follows:
"Transistors are three- or four- terminal devices capable of
amplification, oscillation, frequency conversion, or
switching of electrical currents. The operation of a
transistor depends on the variation in resistivity between
two of the terminals upon the application of an electric
field to the third terminal. The applied control signal or
field is weaker than the resulting action brought about by
the change in resistance and thus amplification results.
Transistors include:
(1) Bipolar transistors, which are three terminal
devices consisting of two diode type junctions,
and whose transistor action depends on both
positive and negative charge carriers (hence,
bipolar).
(2) Field effect transistors (also known as metal oxide
semiconductors (MOS)), which may or may not have a
junction, but which depend on the induced depletion
(or enhancement) of available charge carriers
between two of the terminals. The transistor
action in a field effect transistor employs only
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one type of charge carriers (hence, unipolar).
MOS type transistors which have four terminals
are known as tetrodes."
The BDTM meets the Explanatory Notes description of tran-
sistors. It is a multi-terminal device capable of
amplification, oscillation, frequency conversion, or switching of
electrical currents. Its operation also depends on the variation
in resistivity between two of the terminals upon the application
of an electric field to a third terminal.
The MOS-FET satisfies the Explanatory Note (II) (2)
description of field effect transistors. It is a unipolar metal
oxide semiconductor which depends on the induced depletion or
enhancement of available charge between two terminals.
Lastly, the IGBT also satisfies the Explanatory Notes
description of transistors. It combines both the bipolar
technology of the BDTM as well as the power of the MOS-FET, but
with allowance for greater adaptability. More specifically, it
possesses both the high input impedance and high speed
characteristics of the MOS-FET while it also contains the high
conductivity characteristic of the BDTM transistor.
In sum, all three of the above transistor modules meet the
Explanatory Notes description of how transistors operate
electronically. Also, none of these provisions or any other
section or Chapter notes specifically exclude transistor modules
operating in an identical manner as transistors from heading
8541.
You state that the trade practice of the industry also
supports the classification of the articles in question as
transistors. The Joint Electronic Device Engineering Council
(JEDEC), which is an organization leading a comprehensive and
industry wide effort to harmonize all basic semiconductor
definitions, classifies both BDTM and MOS-FET transistors as
discrete semiconductor devices. The JEDEC defines a discrete
semiconductor device as a "device that is specified to perform
an elementary electronic function and that is not divisible into
separate components functional in themselves." They list
transistors as examples of discrete semiconductor devices, and
state that "other semiconductor structures having the physical
complexity of integrated circuits but performing elementary
electronic functions (e.g., complex Darlington transistors) are
usually considered to be discrete semiconductor devices."
In addition, independent authority recommended to this
office by the Semiconductor Association of San Jose, California,
confirm that the transistor module is considered by the trade to
be a transistor. The Darlington Transistor Module is reported
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by the industry in their statistics as transistors. They are
also not considered to be integrated circuits by the industry.
Thus trade practice as well as the HTSUSA Chapter and Explanatory
Notes, indicate that transistor modules are considered
transistors and not integrated circuits.
Subheading 8542.20.00, HTSUSA, provides for hybrid
integrated circuits. Chapter 85, Note 5(B)(b) states that hybrid
integrated circuits are electronic integrated circuits in which
passive elements, obtained by thin- or thick film technology, and
active elements (transistors etc.), obtained by semiconductor
technology, are combined to all intents and purposes indivisibly,
on a single insulating substrate (glass,ceramic,etc.). In making
a distinction between transistors and integrated circuits,
Explanatory Note 85.42 (II) describes transistors as discrete
components which are indivisible and possess a single active
electrical function. While in contrast, integrated circuits are
described as components consisting of several electric circuit
elements which have multiple electrical functions, and that are
not considered as discrete components. Therefore, the articles
in question can not be considered as the hybrid integrated
circuits described above. They are instead discrete indivisible
components which can only perform a single function and not
multiple circuits that perform multiple functions.
The articles in question are also not hybrid integrated
circuits because they are produced in a different manner than
that which is described in note 5(B)(b) above. All three are
mounted on a Direct Bond Copper Circuit Board which does not
involve the thin/thick film technology traditionally used to
produce hybrid integrated circuits.
HOLDING:
The three transistor modules in question are properly
classifiable as other transistors with a dissipation rate of more
than 1 W, provided for in subheading 8541.29.00, free of duty.
This conclusion regarding dissipation rate is based on the fact
that these articles are used in power circuits. However, if they
in fact do possess a dissipation rate of less than 1 W they would
instead be classifiable in subheading 8541.21.00, free of duty.
Sincerely,
John Durant, Director
Commercial Rulings Division