With 29% of the market for chip inspection equipment, KLA Instruments Corp looks well-nigh impregnable, but semiconductor fabrication equipment manufacturers, notably Applied Materials Inc have been diversifying onto its turf by acquisition. Applied bought Opal Inc and Orbot Instruments Ltd in November for $285m all told. So KLA has pounced on Tencor Instruments Inc and has agreement to acquire it for $1.3bn in shares in a deal that would take its market share to 40% and create a $1bn-a-year firm.