Nippon Steel offers 4-inch SiC substrates
April will see Japanese industrial giant Nippon Steel break into the exclusive ranks of SiC substrate makers selling production volumes of 4-inch wafers.
The company officially releases substrates that boast dislocation densities between 103 and 104 and less than 1 micropipe per square centimeter, on April 1.
“This micropipe density is one of the best in the world,” said Takayuki Yano, manager of the technology development division of Nippon Steel's Advanced Technology Research Institute.
Yano told compoundsemiconductor.net that his company has already been supplying sample substrates to a major Japanese device manufacturer and a number of other compatriot research groups.
Now Nippon Steel is launching a full repertoire of 2-inch, 3-inch and 4-inch 4H crystal polytype semiconducting SiC substrates onto the market.
The wafers will be sold through the Nippon Steel Materials subsidiary that already offers products targeted at the semiconductor industry. Yano explains that this semiconductor focus combined well with Nippon Steel s high-temperature manufacturing expertise in developing SiC crystal growth technology.
“A special process is needed to control the very high temperature, above 2000°C,” Yano explained. “As you know, the steel-making process also uses very high temperatures. Controlling this kind of process is our strong point.”
Japan is leading the way in SiC research, driven in part by the specific inclusion of wide-bandgap semiconductors in the governmental “Cool Earth-Innovative Energy Technology Program”.
This program calls for 6-inch SiC wafers to be available by 2015, with a 102 dislocation density per square centimeter target. This is a call Nippon Steel is seeing echoed by its potential clients.
“We believe that our customer will need to have 6-inch or some kind of large diameter wafers very soon, so we think we have to prepare for this kind of situation,” Yano said.
While Yano was reluctant to give an exact schedule for when Nippon Steel might be able to provide 6-inch substrates, he did say that he expected to see production in “a few years”.
