Abstract: A method for planning product groups is provided. The present method is characterized in that selecting processes from a process group according to the rule of the sum of production capacities of the processes in proportion to the total production capacity of the process group not less than a predetermined ratio and the demand production capacity per month of the processes not less than a predetermined value. Then, defining each of selected processes as a product group. Finally, incorporating the unselected processes of the process group into the product groups according to process resemblance.

Abstract: A method of planning a production schedule by using a planning system, useful for a semiconductor foundry, is provided. When the sales order whose product needs to be subject to the backend process is entered, the planning system subtracts an available amount of the product in the warehouse from the demand of the sales order, and obtaining a balanced amount of the product which is still required. Then the system searches for the supplied amount of the product that can be provided from the foundry and the CTP capacity available for the backend process. The supplied amount is compared with the CTP capacity, and the smaller one is taken as the balanced amount of the product. The available amount of the product in the warehouse is added to the balanced amount of the product, obtaining a total amount of the product as the supply for the sales order.