Method of manufacturing a semiconductor memory device including a transistor
A semiconductor device comprises a plurality of gate structures formed on a substrate, a gate spacer formed on a sidewall of the gate structures, a semiconductor pattern formed on the substrate between the gate structures, a first impurity region and a second impurity region formed in the semiconductor pattern and at surface portions of the substrate, respectively, wherein the first and second impurity regions include a first conductive type impurity, and a channel doping region surrounding the first impurity region, wherein the channel doping region includes a second conductive type impurity.
1. A method of manufacturing a semiconductor device, comprising:
forming a plurality of gate structures on a substrate;
forming a gate spacer on a sidewall of each gate structure;
forming a semiconductor pattern on exposed portions of the substrate between the gate spacers;
forming a channel doping region in the substrate between predetermined adjacent gate spacers by implanting a second conductive type impurity onto the semiconductor pattern; and
forming a first impurity region and a second impurity region in the semiconductor pattern and at surface portions of the substrate by implanting a first conductive type impurity onto the semiconductor pattern, wherein the first impurity region is surrounded by the channel doping region.
2. The method of claim 1 , wherein the semiconductor pattern is formed through a selective epitaxial growth (SEG) process.
3. The method of claim 1 , wherein the second conductive type impurity is implanted deeper than the first conductive type impurity for forming the channel doping region under the first impurity region.
4. The method of claim 1 , further comprising heat-treating the substrate after forming the first and second impurity regions so that the first and second conductive type impurities are diffused to surroundings in the semiconductor pattern and the substrate.
5. The method of claim 4 , wherein the heat-treating is conducted such that the second impurity region is spaced apart from the channel doping region by a predetermined distance.
6. The method of claim 1 , wherein forming the channel doping region includes:
forming a photoresist pattern on the semiconductor pattern and the plurality of gate structures, the semiconductor pattern being exposed through the photoresist pattern between the predetermined adjacent gate spacers; and
implanting the second conductive type impurity into the substrate using the photoresist pattern as an ion implantation mask.
7. The method of claim 1 , further comprising:
forming a first insulation interlayer to cover the gate structures;
forming first and second contact pads through the first insulation interlayer, wherein the first contact pad contacts the first impurity region and the second contact pad contacts the second impurity region;
forming a second insulation interlayer on the first insulation interlayer and the first and second contact pads;
forming a bit line on the second insulation interlayer, wherein the bit line includes a bit line contact formed through the second insulation interlayer for contacting the first contact pad;
forming a third insulation interlayer on the second insulation interlayer to cover the bit line;
forming a storage node contact for contacting the second contact pad through the third insulation interlayer; and
forming a capacitor on the storage node contact.