| 摘要 |
<p>A trench capacitor structure suitable for inclusion in integrated circuit devices and method for forming the same provides increased electrode surface area and capacitance by means of a textured surface of one of the capacitor electrodes. The capacitor (100) is formed in a trench (112) made in of a silicon substrate (110). The inner surface is lined with a textured, doped polysilicon layer (114). the capacitor is completed by forming first a dielectric layer (116) onto the textured layer, then a polysilicon fill (118), capacitor at the contacts are made to the textured polysilicon layer (114) and at the polysilicon fill (118), preferably through the substrate. The textured surface is achieved by differentially etching grain boundaries of a doped polysilicon layer or by direct deposition of hemispherical grain polysilicon to form the electrode. Additional capacitance and contact area can be obtained by additional etching of the trench bottom prior to electrode deposition and dielectric growth. <IMAGE></p> |
