Abstract: Disclosed is a fuel cell system including a fuel cell stack, an enclosure surrounding the fuel cell stack, an air supply line connected to the fuel cell stack and configured to supply air to the fuel cell stack, an air compressor disposed in the air supply line and configured to compress and supply air, a cooler disposed in the air supply line, positioned at a downstream side of the air compressor, and configured to cool the air having passed through the air compressor, a bypass line having one end disposed between the air compressor and the cooler and connected to the air supply line, the other end connected to a separation space between the fuel cell stack and the enclosure, and a circulation line having one end connected to the separation space, the other end disposed at a downstream side of the cooler and connected to the air supply line.

Abstract: A semiconductor device having an improved negative bias temperature instability lifetime characteristic is manufactured by forming a first insulating layer on a substrate, performing a first nitridation on the first insulating layer to form a second insulating layer, and sequentially performing a first and second anneal on the second insulating layer to form a third insulating layer, wherein the second anneal is performed at a higher temperature and with a different gas than the first anneal. A second nitridation is performed on the third insulating layer to form a fourth insulating layer, and a sequential third and fourth anneal on the fourth insulating layer forms a fifth insulating layer. The third anneal is performed at a higher temperature than the first anneal, and the fourth anneal is performed at a higher temperature than the second anneal and with a different gas than the third anneal.

Abstract: A semiconductor device having an improved negative bias temperature instability lifetime characteristic is manufactured by forming a first insulating layer on a substrate, performing a first nitridation on the first insulating layer to form a second insulating layer, and sequentially performing a first and second anneal on the second insulating layer to form a third insulating layer, wherein the second anneal is performed at a higher temperature and with a different gas than the first anneal. A second nitridation is performed on the third insulating layer to form a fourth insulating layer, and a sequential third and fourth anneal on the fourth insulating layer forms a fifth insulating layer. The third anneal is performed at a higher temperature than the first anneal, and the fourth anneal is performed at a higher temperature than the second anneal and with a different gas than the third anneal.