Merck KGaA /zigman2/quotes/200605022/delayed DE:MRK +0.37% said Friday it has signed a definitive agreement to acquire Versum Materials Inc. in a deal with an enterprise value of 5.8 billion euros ($6.6 billion). Merck will pay $53 per Versum share in cash to create a top supplier of high-purity process chemicals, gases and equipment for semiconductor manufacturing, the company said in a statement. The deal is expected to immediately boost Merck's per-share earnings and to close in the second half. Versum's board has terminated its merger agreement with Entegris Inc. /zigman2/quotes/200628784/composite ENTG +0.77% on the grounds that the Merck offer is superior. The deal will be financed with cash on hand and debt via a facilities agreement with Bank of America Merrill Lynch, BNP Paribas Fortis and Deutsche Bank AG. Merck is determined to maintain its strong investment grade rating, it said in a statement. Versum shares were slightly higher premarket, but have gained 38% in the past 12 months, while the S&P 500 /zigman2/quotes/210599714/realtime SPX -0.03% has gained 8%.