Tokyo Electron Limited has conducted performance evaluations on the gas for the past year. As a result of the tests, the gas was found to be a high-performance etching gas for the processing of fine detail work that is known to be difficult to accomplish.
The gas can also be used with currently-employed high- and medium-density oxide film etching systems and has a high etch-selectivity rate for resist and silicon-nitride film that conventional etching gases have never achieved.
The gas has other exceptional characteristics, namely that it does not deplete the ozone layer and has an extremely low global warming factor. We will positively contribute to the preservation of the Earth's environment by promoting the use of ZFL-58.
| 1. | Basic performance |
| ZFL-58 not only avoids depleting the ozone layer,
it also has a very short lifespan in the atmosphere
(0.98 years) compared with conventional gases like
CF4 (50,000 years) and C4F8 (3,200 years). The global
warming factor is also a comparatively low 90 (integrated
value of 100 years with CO2 equal to 1) compared
with conventional gas (CF4: 6500, C4F8: 8700). Thus,
ZFL-58 is an excellent compound with which to preserve
the ozone layer and the Earth's environment. |
|
| 2. | Performance as an etching gas |
| Use of this gas permits a large etch-selectivity
rate for silicon-nitride film, resist and silicon
to silicon oxide film. This feature allows the processing
of the fine detail work required for the coming
generation of logic circuits and giga-bit-class
LSI memory chips, a feat that has been very difficult
to achieve so far. Three processes have been found to be effective: the dual damascene process, the self-aligned contact (SAC) process and the small contact process. These processes have been tested and proven by Tokyo Electron Limited since last year. Tests were carried out not only by Japanese semiconductor manufacturers but also by many other manufacturers in America, Europe, Korea and Taiwan. |
|
| 3. | History of development |
| Since 1989, ZFL-58 has been developed in cooperation
with the National Institute of Materials and Chemical
Research (NIMC), which belongs to the Agency of
Industrial Science and Technology (AIST), part of
Japan's Ministry of International Trade and Industry.
ZEON has been conducting research and development
as a part of our comprehensive C5 fraction utilization
strategy. |
|
| 4. | Production |
| A production plant has already been completed
at ZEON's Takaoka Plant in Takaoka City, Toyama
Prefecture. ZEON plans to exhibit our ZFL-58 etching gas at Semicon-Japan '98 in Makuhari, Chiba Prefecture, from December 2 through 4. |
