KLA-Tencor

(KLAC) - Get Report

reported first-quarter earnings of 54 cents a diluted share, beating analysts' estimates.

According to a

First Call/Thomson Financial

survey, 21 analysts were expecting the company to earn 51 cents a share for the quarter. The company earned 19 cents a share a year ago.

First-quarter revenue rose to $534.6 million from $273 million.

KLA-Tencor, which makes yield management and process control systems for the semiconductor industry, ended the quarter with more than six months of backlog at current shipping levels.