A semiconductor device includes a first buried bit line (120a) provided between lower and upper substrates (100b, 100a), first and second pillar patterns (105a, 105b) extending from the upper substrate (100a) and coupled to the first buried bit line (120a) through first and second gate patterns (140a), respectively. A first body contact pattern (160a) coupled to the first and/or the second pillar patterns (105a, 105b) through the upper substrate (100a) prevents the first and the second pillar patterns from floating.