A semiconductor memory device and method for making the same. The semiconductor memory device includes an active layer spaced apart from a substrate, extending in a direction parallel to the substrate, and including a channel; a bit line extending in a vertical direction to the substrate and contacting a first end portion of the active layer; a capacitor contacting a second end portion of the active layer; a word line including a high work function electrode adjacent to the bit line and a low work function electrode adjacent to the capacitor; a first gate dielectric layer disposed between the low work function electrode and the active layer; and a second gate dielectric layer disposed between the high work function electrode and the active layer, the second gate dielectric layer being thinner than the first gate dielectric layer.

A method of manufacturing a semiconductor memory device and a semiconductor memory device, the method including providing a substrate that includes a cell array region and a peripheral circuit region; forming a mask pattern that covers the cell array region and exposes the peripheral circuit region; growing a semiconductor layer on the peripheral circuit region exposed by the mask pattern such that the semiconductor layer has a different lattice constant from the substrate; forming a buffer layer that covers the cell array region and exposes the semiconductor layer; forming a conductive layer that covers the buffer layer and the semiconductor layer; and patterning the conductive layer to form conductive lines on the cell array region and to form a gate electrode on the peripheral circuit region.

The embodiments of the present disclosure provide an etching method, an air-gap dielectric layer, and a dynamic random-access memory. The etching method is configured to selectively etch a silicon oxide film on a wafer surface that includes the silicon oxide film and a silicon nitride film. In addition, the etching method includes: a surface layer removal process including: etching the silicon oxide film at a first etching rate and removing a surface modification layer covering on the silicon nitride film; and an etching process including: etching the silicon oxide film at a second etching rate. The first etching rate is smaller than the second etching rate. In the etching method according to the present disclosure, through selectively etching the silicon oxide film, a substantial degradation of an etching selectivity ratio of SiO.sub.2/SiN caused by the surface modification layer on the wafer surface can be avoided. Through making the first etching rate smaller than the second etching rate, a highly efficient etching process is ensured and at the same time, excessive etching can be avoided in the surface layer removal process, thereby further ensuring the high etching selectivity ratio.

Memory devices may include a source region, channels, a gate insulation layer pattern, a selection gate pattern, a first gate pattern, a second gate pattern and a drain region. The source region may include first impurities having a first conductivity type at an upper portion of a substrate. The channels may contact the source region. Each of the channels may extend in a vertical direction that is perpendicular to an upper surface of the substrate. The selection gate pattern may be on sidewalls of the channels. The first gate pattern may be on the sidewalls of the channels. The first gate pattern may be a common electrode of all of multiple channels. The second gate patterns may be on the sidewalls of the channels. The drain region may include second impurities having a second conductivity type that is different from the first conductivity type at an upper portion of each of the channels.

Techniques for fabricating semiconductor structures and devices with stacked structures having embedded capacitors are disclosed. In one example, a semiconductor structure includes a substrate having a first region and a second region. The semiconductor structure further includes a capacitor structure disposed in the second region of the substrate. The capacitor structure includes a capacitor conductor and a dielectric insulator disposed between the capacitor conductor and the substrate. The semiconductor structure further includes a stacked device disposed on the first region of the substrate. The stacked device includes a first transistor and a second transistor. At least a portion of the second transistor is disposed under at least a portion of the first transistor. The first transistor and the second transistor are each coupled to the capacitor conductor.

A semiconductor memory device includes a stack structure comprising a plurality of layers vertically stacked on a substrate, each layer including a semiconductor pattern, a gate electrode extending in a first direction on the semiconductor pattern, and a data storage element electrically connected to the semiconductor pattern, a plurality of vertical insulators penetrating the stack structure, the vertical insulators arranged in the first direction, and a bit line provided at a side of the stack structure and extending vertically. The bit line electrically connects the semiconductor patterns which are stacked. Each of the vertical insulators includes first and second vertical insulators adjacent to each other. The gate electrode includes a connection portion disposed between the first and second vertical insulators.

The semiconductor device includes a first conductor and a second conductor; a first insulator to a third insulator; and a first oxide to a third oxide. The first conductor is disposed to be exposed from a top surface of the first insulator. The first oxide is disposed over the first insulator and the first conductor. A first opening reaching the first conductor is provided in the first oxide. The second oxide is disposed over the first oxide. The second oxide comprises a first region, a second region, and a third region positioned between the first region and the second region. The third oxide is disposed over the second oxide. The second insulator is disposed over the third oxide. The second conductor is disposed over the second insulator. The third insulator is disposed to cover the first region and the second region and to be in contact with the top surface of the first insulator.

A semiconductor device that can be miniaturized or highly integrated is provided. The semiconductor device includes a capacitor, an electrode, and an interlayer film. The transistor includes a semiconductor layer, a gate, a source, and a drain; the transistor and the capacitor are placed to be embedded in the interlayer film. Below the semiconductor layer, one of the source and the drain is in contact with the electrode. Above the semiconductor layer, the other of the source and the drain is in contact with one electrode of the capacitor.

A semiconductor structure with a capacitor landing pad includes a substrate. A capacitor contact plug is disposed on the substrate. A capacitor landing pad contacts and electrically connects the capacitor contact plug. A bit line is disposed on the substrate. A dielectric layer surrounds the capacitor landing pad. The dielectric layer includes a bottom surface lower than a top surface of the bit line.

Disclosed is a three-dimensional integrated system for DRAM chips and a fabrication method thereof. A plurality of trench structures are etched on the front and back of a silicon wafer; then, a TSV structure is etched between the two upper and lower trenches opposite to each other for electrical connection; then, DRAM chips are placed in the trenches, and copper-copper bonding is used to make the chips electrically connected to the TSV structure in a vertical direction; finally, redistribution is done to make the chips in a horizontal direction electrically connected. The invention can make full use of silicon materials, and can avoid problems such as warpage and deformation of an interposer. In addition, placing the chips in the trenches will not increase the overall package thickness, while protecting the chips from external impact.