The world’s largest semiconductor-equipment manufacturer has invested more than $100 million to expand its facility in Connecticut over the past few years. But market demand means ASML is making another investment in its Wilton campus. ASML’s photo-lithography machine is used by customer to mass-produce microchips, an essential component of hardware that ranges from smartphones to cars. A groundbreaking ceremony was held yesterday with some of Connecticut’s top elected officials to mark the $200 million expansion on Danbury Road. The project will add about 37,000 square feet to their facility and will include more space for core operations, such as manufacturing in the “cleanroom” area and creation of an “experience center,” which will be open to students. The construction is scheduled to be completed by the end of 2024. The company currently employs 2,500 people in Wilton, but is planning to add about 1,000 jobs during the next two years. The company is headquartered in the Netherlands.