US 7,321,146 B2
DRAM memory cell and method of manufacturing the same
Cheol-ju Yun, Kyungki-do (Korea, Republic of); and Sun-hoo Park, Kyungki-do (Korea, Republic of)
Assigned to Samsung Electronics Co., Ltd., Suwon-si, Gyeonggi-do (Korea, Republic of)
Filed on Feb. 10, 2006, as Appl. No. 11/352,179.
Application 11/352179 is a division of application No. 10/704514, filed on Nov. 07, 2003, granted, now 7,030,439.
Claims priority of application No. 2003-16302 (KR), filed on Mar. 15, 2003.
Prior Publication US 2006/0124979 A1, Jun. 15, 2006
Int. Cl. H01L 27/108 (2006.01)
U.S. Cl. 257—300  [257/306; 257/E21.019; 257/E21.649; 257/E27.086; 438/253] 12 Claims
OG exemplary drawing
 
1. A method of manufacturing a DRAM memory cell, the method comprising:
forming word line structures on a semiconductor substrate where active regions are defined;
forming drains and sources in the active regions on both sides of the word line structures;
forming a first interlayer dielectric on the semiconductor substrate where the word line structures are formed;
forming first contact pads and second contact pads in the first interlayer dielectric to contact the drains and sources, respectively;
forming a second interlayer dielectric on the semiconductor substrate where the first contact pads and the second contact pads are formed;
forming bit line structures on the second interlayer dielectric, the bit line structures being disposed perpendicularly to the word lines and being electrically connected to the first contact pads;
depositing an insulating layer on the second interlayer dielectric on which the bit line structures are formed;
forming storage node contact holes that expose the second contact pads by etching the insulating layer such that an entrance portion of the storage node contact holes extends in a direction parallel to a longitudinal axis of the bit line structures so as to be wider than a contact portion of the storage node contact holes;
forming storage node contact plugs by filling the storage node contact holes with a conductive material; and forming storage node electrodes to contact the storage node plugs.