A process for forming an IC isolation trench pattern wherein the trenches have varying widths and are filled with near intrinsic single crystal silicon. Thus, the wiring that passes over the trenches has low capacitance and active circuit devices having improved high frequency performance can be fabricated into the silicon in the trenches. This increases the utilization of surface area thereby increasing active device density for VLSI applications.
The present invention discloses a method of forming a field oxide film of a semiconductor device which can minimize a bird's beak by etching a predetermined portion of a silicon substrate, forming a field oxide film and forming a single crystal silicon layer on the etched silicon substrate.
A semiconductor memory device having an excellent data holding characteristics because of a small leak current from a trench and a process for producing the same are disclosed. An SiO.sub.2 film 12 having an appropriate pattern is formed on a P type silicon substrate 11. Trenches 14 are relatively formed on the SiO.sub.2 film 12 by selectively growing a P type epitaxial layer 13 on the silicon substrate 11 using the SiO.sub.2 film 12 as a mask. An N type layer 23 acting as an electrode of a capacitor 27 is formed on the inner wall of the trench 14 by the oblique ion implantation of impurities 22 thereto. A polycrystalline silicon film 25 acting as an opposite electrode of the capacitor 27 is formed on an ONO film 24 so that the ONO film 24 is disposed between the polysilicon film 25 and the SiO.sub.2 film. The semiconductor memory device which is produced by this method without etching to form the trenches 14 has a fewer crystal defects in the epitaxial layer 13 around the trenches 14. Accordingly, the data holding characteristics are improved since the leak current from the trenches 14 becomes less. As a result of this, higher density integration is possible since the device can be made with less capacitance of capacitors.
A semiconductor device having a trench isolation region including an anti-oxidative liner formed to be thin enough to minimize etch wastage caused by a wet etching solution according to a wet loading effect, and a trench isolation method of forming the same. The semiconductor device includes a silicon substrate and a trench isolation region formed in the silicon substrate. A silicon epitaxial growth layer contacts the silicon substrate at a bottom surface of the trench isolation region and fills the lower half of the trench isolation region. A first oxide layer has an L-shaped cross-section and extends from a sidewall of the trench isolation region to a portion of the bottom surface of the trench isolation region. An anti-oxidative liner has an L-shaped cross-section, and extends between the first oxide layer and the silicon epitaxial growth layer, with its inner surface contacting the silicon epitaxial growth layer. A second oxide layer fills the upper half of the trench isolation region on the silicon epitaxial growth layer.
A method is described for manufacturing a shallow trench isolation. The method comprises the steps of providing a substrate having a pad oxide layer, a mask layer and a trench, wherein the trench penetrates through the mask layer and the pad oxide layer and into the substrate. A liner oxide layer is formed on a portion of the sidewall of the trench in the substrate. A silicon layer is formed in the trench with a same surface level as the interface between the substrate and the pad oxide layer and an insulating layer is formed on the silicon layer.
A semiconductor device having a trench isolation region including an anti-oxidative liner formed to be thin enough to minimize etch wastage caused by a wet etching solution according to a wet loading effect, and a trench isolation method of forming the same. The semiconductor device includes a silicon substrate and a trench isolation region formed in the silicon substrate. A silicon epitaxial growth layer contacts the silicon substrate at a bottom surface of the trench isolation region and fills the lower half of the trench isolation region. A first oxide layer has an L-shaped cross-section and extends from a sidewall of the trench isolation region to a portion of the bottom surface of the trench isolation region. An anti-oxidative liner has an L-shaped cross-section, and extends between the first oxide layer and the silicon epitaxial growth layer, with its inner surface contacting the silicon epitaxial growth layer. A second oxide layer fills the upper half of the trench isolation region on the silicon epitaxial growth layer.
