Shareholders of Singapore's Chartered Semiconductor Manufacturing have approved an offer by Abu Dhabi to buy the world's third-biggest maker of customized chips for S$2.5bn ($1.8bn), the chairman of the Singaporean company said today. Advanced Technology Investment Co., an investment company owned by Abu Dhabi, will pay S$2.68 ($1.86) a share in cash for Chartered Semiconductor, ATIC said in September. Abu Dhabi plans to combine the maker of chips used in Microsoft Corp.'s Xbox 360 game console with Globalfoundries, a venture ATIC created with Advanced Micro Devices last year, to create a challenger to United Microelectronics, the world's second-biggest maker of customized chips, according to Bloomberg.