Demand for semiconductor equipment in February was the highest in three years, the latest sign that the industry is experiencing a solid rebound from the tech spending slump of recent years, according to a closely-watched industry report. Semiconductor Equipment and Materials International's monthly figures released late Thursday said manufacturers posted $1.31 billion in global orders during the month, with a book-to bill ratio of 1.14, slightly below the consensus estimate of 1.16 and January's ratio. Bookings were up 6% from January and 72% from year-ago levels, while billings in February were up about 10% from the previous month and 48% from February of last year. The group's revised book-to-bill ratio for January was 1.19. The booking and billing figures are based on three-month averages. Chipmaker shares were up slightly in premarket trading. Intel ( INTC), for instance, was up 10 cents, or 0.4%, to $27.30.