CLA-2-84:S:N:N1:103 855845
Mr. Shumei Nagaya
Kokusai Electric Co., Ltd. America
3000 Marcus Avenue, Suite 3E11
Lake Success, N.Y. 11042
RE: The tariff classification of semiconductor manufacturing
machines from Japan
Dear Mr. Nagaya:
In your letter dated August 20, 1990 you requested a tariff
classification ruling.
With your inquiry you submitted a brochure describing the
Vertron Model DD802V oxidation/diffusion system and the Vertron
Model DJ802V low pressure chemical vapor deposition (LPCVD)
system. The Model DD802V is a furnace designed to oxidize and/or
diffuse silicon wafers. The wafers are initially placed in a
reactor tube within the unit by means of an automatic wafer
cassette transfer mechanism, and the tube is heated to a
temperature of approximately 1000 degrees Centigrade. To
accomplish oxidation, the tube is filled with oxygen at
atmospheric pressure. This results in thermal oxidation of the
wafer and the formation of a layer of silicon dioxide on the
wafer surface. To accomplish diffusion, which requires that
chemical impurities known as dopants be placed into specific
regions of the wafer, the wafer is exposed to a gaseous
concentration of the dopant within the tube, causing the dopant
to diffuse into the wafer. Diffusion masks are used to prevent
the dopant from entering adjacent regions of the wafer.
The Model DJ802V LPCVD system is used to deposit thin films
onto the surface of the silicon wafer. The reaction tube is
heated to a temperature of approximately 800 degrees centigrade
and air is evacuated from the tube by means of vacuum pumps. The
wafer is then exposed to the appropriate gases which have been
combined in the partially evacuated reaction tube. The
resulting reaction causes the gases to be uniformly deposited
onto the surface of the wafer, thus producing a thin film.
You have stated in your letter that the Model DD802V is
specifically designed for oxidation/diffusion, and the Model
DJ802V is specifically designed for low pressure chemical vapor
deposition. You have further stated that they cannot be used
interchangeably, and that the LPCVD system cannot be converted
into an oxidation/diffusion system and vice versa. While the
Model DD802V is similar to the Model DJ802V, the latter contains
vacuum pumps and the chamber and associated equipment are
constructed to vacuum specifications. In addition, the operating
temperatures, heater construction and power requirements for the
two models are different.
The applicable subheading for the Model DD802V
oxidation/diffusion system will be 8514.30.0040, Harmonized
Tariff Schedule of the United States (HTS), which provides for
other industrial or laboratory electric furnaces for diffusion,
oxidation or annealing of semiconductor wafers. The rate of
duty will be 2.5 percent ad valorem.
The applicable subheading for the Model DJ802V low pressure
chemical vapor deposition system will be 8479.89.9076, HTS, which
provides for other machines and mechanical appliances having
individual functions, not specified or included elsewhere:
chemical vapor deposition apparatus including low pressure and
plasma enhanced systems. The rate of duty will be 3.7 percent ad
valorem.
This ruling is being issued under the provisions of Section
177 of the Customs Regulations (19 C.F.R. 177).
A copy of this ruling letter should be attached to the entry
documents filed at the time this merchandise is imported. If the
documents have been filed without a copy, this ruling should be
brought to the attention of the Customs officer handling the
transaction.
Sincerely,
Jean F. Maguire
Area Director
New York Seaport