Silicon nitride island formation for increased capacitance

• Main Authors: Chudzik, Michael P, Beintner, Jochen, Shepard, Jr., Joseph F
• Format: Patent
• Language: English
• Published: 03.08.2004

Semiconductor devices are employed in various systems in a wide variety of applications. An important type of semiconductor device used as a memory is known as dynamic random access memory ("DRAM"). The DRAM is extensively used for memory in computers and other electronic devices. A basic DRAM cell may include a capacitor and a transistor each formed in a semiconductor substrate. The capacitor stores a charge to represent a data value. The transistor allows the data value to be refreshed, read from, or written to the capacitor. illustrates a conventional DRAM memory cell including a capacitor and a transistor . The capacitor includes a first electrode and a second electrode . The transistor includes a source (or drain) connected to the second electrode . The transistor also includes a drain (or source) connected to a bit line , as well as a gate connected to a word line . The data value may be refreshed, read from or written to the capacitor by applying appropriate voltages to the bit line and/or the word line . A semiconductor device is fabricated using a micro-masking structure. The micro-masking structure is formed along the sidewalls of a trench in a semiconductor substrate or along the sidewalls of an electrode disposed over the semiconductor substrate. The micro-masking structure exposes portions of the sidewalls and covers other portions of the sidewalls. Then the exposed portions of the sidewalls are recessed to form a plurality of recesses such that the sidewalls have an increase surface area. After the recessing, the micro-masking structure is removed. The recessed sidewalls provide enhanced capacitance.