Novellus Systems Inc. (NVLS) Chief Executive Richard Hill said he believes the long-depressed market for semiconductor equipment is improving.

"We believe the worst is behind us," said Hill in a conference call to update the company's second-quarter outlook.

Novellus, which makes the tools used to make semiconductors, left unchanged its views on second-quarter revenue, gross margins and loss per share, but raised its estimates for bookings growth.

The company now expects booked orders will grow 30% to 55% from the previous period. Novellus had expected growth of 20% to 50%.

In April, Novellus said it expected second-quarter sales of $110 million to $125 million and a loss per share of 35 to 45 cents.

Novellus shares were recently up 0.5% to $17.99. The stock is up more than 40% over the past three months, but still trades below its 52-week high of $24.09.

Despite the improving industry conditions - Hill said some markets were "marginally better" - he voiced caution about a quick return to strong demand for chip equipment.

"We're not going to go back to the robust economic situation we were in a year and a half or two years ago," Hill said.

-By Jerry A. DiColo; Dow Jones Newswires; 201-938-5670; jerry.dicolo@dowjones.com