The Gunners must overturn a 1-0 deficit to reach the Wembley final.
"We have a team from the Championship coming to the Emirates and they probably won't fancy it too much, but we fancy our chances and are confident we will go through," said Szczesny, who has impressed after taking his chance in goal. "We are Arsenal and believe we can beat anybody."
Szczesny added: "They have a one-goal advantage which they will try to defend, but as soon as we score the first goal, it will be downhill for them.
"We just have to break them down and score as many goals as we can. We are confident we can turn this around."