Abstract: A method for forming a semiconductor device. A substrate is provided, wherein the substrate has recessed gates and deep trench capacitor devices therein. Protrusions of the recessed gates and upper portions of the deep trench capacitor devices are revealed. Spacers are formed on sidewalls of the upper portions and the protrusions. Buried portions of conductive material are formed in spaces between the spacers. The substrate, the spacers and the buried portions to form parallel shallow trenches are patterned to form parallel shallow trenches for defining active regions. A layer of dielectric material is formed in the shallow trenches, wherein some of the buried portions serve as buried contacts.

Abstract: A small-size (w<0.5 micrometers) alignment mark in combination with a “k1 process” is proposed, which is particularly suited for the fabrication of trench-capacitor DRAM devices which requires highly accurate AA-DT alignment. The “k1 process” is utilized to etch away polysilicon studded in the alignment mark trenches and refresh the trench profile prior to AA pattern transferring, thereby improving wafer alignment accuracy and precision.

Abstract: A method of fabricating a semiconductor device having a trench gate is provided. First, a semiconductor substrate having a trench etch mask thereon is provided. The semiconductor substrate is etched to form a first trench having a first depth using the trench etch mask as a shield. Impurities are doped into the semiconductor substrate through the first trench to form a doped region. The doped region and the semiconductor substrate underlying the first trench are etched to form a second trench having a second depth greater than the first depth, wherein the second trench has a sidewall and a bottom. A gate insulating layer is formed on the sidewall and the bottom of the second trench. A trench gate is formed in the second trench.

Abstract: A method for forming a semiconductor device is provided. The method comprises providing a substrate with recessed gates and deep trench capacitor devices therein. Protrusions of the recessed gates and upper portions of the deep trench capacitor devices are revealed. Spacers are formed on sidewalls of the upper portions and the protrusions. Buried portions of conductive material are formed in spaces between the spacers. The substrate, the spacers and the buried portions are patterned to form parallel shallow trenches for defining buried bit line contacts and capacitor buried surface straps. A layer of dielectric material is formed in the shallow trenches. Word lines are formed across the recessed gates. Bit lines are formed to electrically connect the buried bit line contacts without crossing the capacitor buried surface straps, and stack capacitors are formed to electrically connect with the capacitor buried surface straps. A semiconductor device is also provided.

Abstract: A method for forming a semiconductor device is provided. The method comprises providing a substrate with recessed gates and deep trench capacitor devices therein. Protrusions of the recessed gates and upper portions of the deep trench capacitor devices are revealed. Spacers are formed on sidewalls of the upper portions and the protrusions. Buried portions of conductive material are formed in spaces between the spacers. The substrate, the spacers and the buried portions are patterned to form parallel shallow trenches for defining buried bit line contacts and capacitor buried surface straps. A layer of dielectric material is formed in the shallow trenches. Word lines are formed across the recessed gates. Bit lines are formed to electrically connect the buried bit line contacts without crossing the capacitor buried surface straps, and stack capacitors are formed to electrically connect with the capacitor buried surface straps. A semiconductor device is also provided.

Abstract: A method for forming a semiconductor memory device with a recessed gate is disclosed. A substrate with a pad layer thereon is provided. The pad layer and the substrate are patterned to form at least two trenches. A deep trench capacitor is formed in each trench. A protrusion is formed on each deep trench capacitor, wherein a top surface level of each protrusion is higher than that of the pad layer. Spacers are formed on sidewalls of the protrusions, and the pad layer and the substrate are etched using the spacers and the protrusions as a mask to form a recess. A recessed gate is formed in the recess.

Abstract: A method for forming a semiconductor device. A substrate is provided, wherein the substrate has recessed gates and deep trench capacitor devices therein. Protrusions of the recessed gates and upper portions of the deep trench capacitor devices are revealed. Spacers are formed on sidewalls of the upper portions and the protrusions. Buried portions of conductive material are formed in spaces between the spacers. The substrate, the spacers and the buried portions are patterned to form parallel shallow trenches for defining active regions. A layer of dielectric material is formed in the shallow trenches, wherein some of the buried portions serve as buried bit line contacts. Word lines are formed across the recessed gates, wherein at least one of the word lines comprises portions overlapping the recessed gates. At least one of the overlapped portions has a narrower width than at least one of the recessed gates.

Abstract: A method for forming a semiconductor device. A substrate, having a plurality of deep trench capacitors therein, is provided wherein upper portions of the deep trench capacitor devices are revealed. Spacers on sidewalls of the upper portions of the deep trench capacitors are formed to form a predetermined region surrounded by the deep trench capacitor devices. The predetermined region of the substrate is etched using the spacers and the upper portions of the deep trench capacitors serve as a mask to form a recess, and a recessed gate is formed in the recess.

Abstract: A method for forming a recess. The method includes providing a substrate with two protrusions having a first side wall and a second side wall opposite to the first side wall disposed above the substrate, conformally forming a mask layer on the substrate and the protrusions, tilt implanting the mask layer using a first implanting mask adjacent to the first side wall of the protrusions, removing implanted portions of the mask layer to form a patterned mask layer, and etching the substrate using the patterned mask layer, thereby forming a recess.

Abstract: A method of fabricating self-aligned gate trench utilizing TTO poly spacer is disclosed. A semiconductor substrate having thereon a pad oxide layer and pad nitride layer is provided. A plurality of trench capacitors are embedded in a memory array region of the semiconductor substrate. Each of the trench capacitors has a trench top oxide (TTO) that extrudes from a main surface of the semiconductor substrate. Poly spacers are formed on two opposite sides of the extruding TTO and are used, after oxidized, as an etching hard mask for etching a recessed gate trench in close proximity to the trench capacitor.

Abstract: A method of fabricating a semiconductor device having a trench gate is provided. First, a semiconductor substrate having a trench etch mask thereon is provided. The semiconductor substrate is etched to form a trench having a sidewall and a bottom using the trench etch mask as a shield. Impurities are doped into the semiconductor substrate through the trench to form a doped region. The semiconductor substrate underlying the trench is etched to form an extended portion. A gate insulating layer is formed on the trench and the extended portion. A trench gate is formed in the trench and the extended portion.

Abstract: A small-size (w<0.5 micrometers) alignment mark in combination with a “k1 process” is proposed, which is particularly suited for the fabrication of trench-capacitor DRAM devices which requires highly accurate AA-DT and GC-DT overlay alignment. The “k1 process” is utilized to etch away polysilicon studded in the alignment mark trenches and to refresh the trench profile, thereby improving overlay alignment accuracy and precision.

Abstract: A method of fabricating self-aligned recess utilizing asymmetric poly spacer is disclosed. A semiconductor substrate having thereon a first pad layer and second pad layer is provided. A plurality of trenches is embedded in a memory array region of the semiconductor substrate. Each of the trenches includes a trench top layer that extrudes from a main surface of the semiconductor substrate. Asymmetric poly spacer is formed on one side of the extruding trench top layer and is used, after oxidized, as a mask for forming a recess in close proximity to the trenches.

Abstract: A method for forming a semiconductor device is provided. The method comprises providing a substrate with recessed gates and deep trench capacitor devices therein. Protrusions of the recessed gates and upper portions of the deep trench capacitor devices are revealed. Spacers are formed on sidewalls of the upper portions and the protrusions. Buried portions of conductive material are formed in spaces between the spacers. The substrate, the spacers and the buried portions are patterned to form parallel shallow trenches for defining buried bit line contacts and capacitor buried surface straps. A layer of dielectric material is formed in the shallow trenches. Word lines are formed across the recessed gates. Bit lines are formed to electrically connect the buried bit line contacts without crossing the capacitor buried surface straps, and stack capacitors are formed to electrically connect with the capacitor buried surface straps. A semiconductor device is also provided.

Abstract: A method of fabricating a semiconductor device having a trench gate is provided. First, a semiconductor substrate having a trench etch mask thereon is provided. The semiconductor substrate is etched to form a first trench having a first depth using the trench etch mask as a shield. Impurities are doped into the semiconductor substrate through the first trench to form a doped region. The doped region and the semiconductor substrate underlying the first trench are etched to form a second trench having a second depth greater than the first depth, wherein the second trench has a sidewall and a bottom. A gate insulating layer is formed on the sidewall and the bottom of the second trench. A trench gate is formed in the second trench.

Abstract: A method for forming a recess. The method includes providing a substrate with two protrusions having a first side wall and a second side wall opposite to the first side wall disposed above the substrate, conformally forming a mask layer on the substrate and the protrusions, tilt implanting the mask layer with a first angle using a first implanting mask adjacent to the first side wall of the protrusions, tilt implanting the mask layer with a second angle using a second implanting mask adjacent to the second side wall of the protrusions, removing implanted portions of the mask layer to form a patterned mask layer, and etching the substrate using the patterned mask layer, thereby forming a recess, wherein distances from the recess to the two protrusions, respectively, are different.

Abstract: A method for forming a recess. The method includes providing a substrate with two protrusions having a first side wall and a second side wall opposite to the first side wall disposed above the substrate, conformally forming a mask layer on the substrate and the protrusions, tilt implanting the mask layer with a first angle using a first implanting mask adjacent to the first side wall of the protrusions, tilt implanting the mask layer with a second angle using a second implanting mask adjacent to the second side wall of the protrusions, removing implanted portions of the mask layer to form a patterned mask layer, and etching the substrate using the patterned mask layer, thereby forming a recess, wherein distances from the recess to the two protrusions, respectively, are different.

Abstract: A method for forming a recess. The method includes providing a substrate with two protrusions having a first side wall and a second side wall opposite to the first side wall disposed above the substrate, conformally forming a mask layer on the substrate and the protrusions, tilt implanting the mask layer using a first implanting mask adjacent to the first side wall of the protrusions, removing implanted portions of the mask layer to form a patterned mask layer, and etching the substrate using the patterned mask layer, thereby forming a recess.

Abstract: A method for forming a semiconductor device. A substrate, having a plurality of deep trench capacitors therein, is provided wherein upper portions of the deep trench capacitor devices are revealed. Spacers on sidewalls of the upper portions of the deep trench capacitors are formed to form a predetermined region surrounded by the deep trench capacitor devices. The predetermined region of the substrate is etched using the spacers and the upper portions of the deep trench capacitors serve as a mask to form a recess, and a recessed gate is formed in the recess.

Abstract: A method for forming a semiconductor device. A substrate with a pad layer thereon is provided. The pad layer and the substrate are patterned to form at least two trenches. A deep trench capacitor is formed in each trench. A protrusion is formed on each deep trench capacitor, wherein a top surface level of each protrusion is higher than that of the pad layer. Spacers are formed on sidewalls of the protrusions, and the pad layer and the substrate are etched using the spacers and the protrusions as a mask to form a recess. A recessed gate is formed in the recess.