Abstract: An alternating stack of insulating layers and spacer material layers is formed over a semiconductor substrate. Memory openings are formed through the alternating stack. An optional silicon-containing epitaxial pedestal and a memory film are formed in each memory opening. After forming an opening through a bottom portion of the memory film within each memory opening, a germanium-containing semiconductor layer and a dielectric layer is formed in each memory opening. Employing the memory film and the dielectric layer as a crucible, a liquid phase epitaxy anneal is performed to convert the germanium-containing semiconductor layer into a germanium-containing epitaxial channel layer. A dielectric core and a drain region can be formed over the dielectric layer. The germanium-containing epitaxial channel layer is single crystalline, and can provide a higher charge carrier mobility than a polysilicon channel.

Abstract: A linear mark extending perpendicular to a primary step direction of stepped terrace for a three-dimensional memory device can be employed as a reference feature for aligning a trimming material layer before initiating an etch-and-trim process sequence. The linear mark can be formed as a linear trench or a linear rail structure. The distance between a sidewall of each trimming material layer and the linear mark can be measured at multiple locations that are laterally spaced apart perpendicular to the primary step direction to provide statistically significant data points, which can be employed to provide an enhanced control of the staircase patterning process. Likewise, locations of patterned stepped surfaces can be measured at multiple locations to provide enhanced control of the locations of vertical steps in the stepped terrace.

Abstract: An alternating stack of insulating layers and spacer material layers is formed over a semiconductor substrate. Memory openings are formed through the alternating stack. An optional silicon-containing epitaxial pedestal and a memory film are formed in each memory opening. After forming an opening through a bottom portion of the memory film within each memory opening, a germanium-containing semiconductor layer and a dielectric layer is formed in each memory opening. Employing the memory film and the dielectric layer as a crucible, a liquid phase epitaxy anneal is performed to convert the germanium-containing semiconductor layer into a germanium-containing epitaxial channel layer. A dielectric core and a drain region can be formed over the dielectric layer. The germanium-containing epitaxial channel layer is single crystalline, and can provide a higher charge carrier mobility than a polysilicon channel.

Abstract: A linear mark extending perpendicular to a primary step direction of stepped terrace for a three-dimensional memory device can be employed as a reference feature for aligning a trimming material layer before initiating an etch-and-trim process sequence. The linear mark can be formed as a linear trench or a linear rail structure. The distance between a sidewall of each trimming material layer and the linear mark can be measured at multiple locations that are laterally spaced apart perpendicular to the primary step direction to provide statistically significant data points, which can be employed to provide an enhanced control of the staircase patterning process. Likewise, locations of patterned stepped surfaces can be measured at multiple locations to provide enhanced control of the locations of vertical steps in the stepped terrace.

Abstract: Techniques for forming 3D memory arrays are disclosed. Memory openings are filled with a sacrificial material, such as silicon or nitride. Afterwards, a replacement technique is used to remove nitride from an ONON stack and replace it with a conductive material such as tungsten. Afterwards, memory cell films are formed in the memory openings. The conductive material serves as control gates of the memory cells. The control gate will not suffer from corner rounding. ONON shrinkage is avoided, which will prevent control gate shrinkage. Block oxide between the charge storage region and control gate may be deposited after control gate replacement, so the uniformity is good. Block oxide may be deposited after control gate replacement, so TiN adjacent to control gates can be thicker to prevent fluorine attacking the insulator between adjacent control gates. Therefore, control gate to control gate shorting is prevented.

Abstract: Techniques for forming 3D memory arrays are disclosed. Memory openings are filled with a sacrificial material, such as silicon or nitride. Afterwards, a replacement technique is used to remove nitride from an ONON stack and replace it with a conductive material such as tungsten. Afterwards, memory cell films are formed in the memory openings. The conductive material serves as control gates of the memory cells. The control gate will not suffer from corner rounding. ONON shrinkage is avoided, which will prevent control gate shrinkage. Block oxide between the charge storage region and control gate may be deposited after control gate replacement, so the uniformity is good. Block oxide may be deposited after control gate replacement, so TiN adjacent to control gates can be thicker to prevent fluorine attacking the insulator between adjacent control gates. Therefore, control gate to control gate shorting is prevented.

Abstract: Memory devices having an increased effective channel length and/or improved TPD characteristics, and methods of making the memory devices are provided. The memory devices contain two or more memory cells on a semiconductor substrate and bit line dielectrics between the memory cells. The memory cell contains a charge trapping dielectric stack, a poly gate, a pair of pocket implant regions, and a pair of bit lines. The bit line can be formed by an implant process at a higher energy level and/or a higher concentration of dopants without suffering device short channel roll off issues because spacers at bit line sidewalls constrain the implant in narrower implant regions.

Abstract: Memory devices having improved TPD characteristics and methods of making the memory devices are provided. The memory devices contain two or more memory cells on a semiconductor substrate and bit line openings containing a bit line dielectric between the memory cells. The memory cell contains a charge storage layer and a first poly gate. The bit line opening extends into the semiconductor substrate. By containing the bit line dielectric in the bit line openings that extend into the semiconductor substrate, the memory device can improve the electrical isolation between memory cells, thereby preventing and/or mitigating TPD.

Abstract: A NAND flash memory chip includes wide openings in an inter-poly dielectric layer through which gaps are later etched to define structures such as select gates. Such select gates are asymmetric, with inter-poly dielectric on a side adjacent to a memory cell and no inter-poly dielectric on a side away from a memory cell. Gaps etched through such openings may also define peripheral devices.

Abstract: Memory devices having an increased effective channel length and/or improved TPD characteristics, and methods of making the memory devices are provided. The memory devices contain two or more memory cells on a semiconductor substrate and bit line dielectrics between the memory cells. The memory cell contains a charge trapping dielectric stack, a poly gate, a pair of pocket implant regions, and a pair of bit lines. The bit line can be formed by an implant process at a higher energy level and/or a higher concentration of dopants without suffering device short channel roll off issues because spacers at bit line sidewalls constrain the implant in narrower implant regions.

Abstract: A NAND flash memory chip includes wide openings in an inter-poly dielectric layer through which gaps are later etched to define structures such as select gates. Such select gates are asymmetric, with inter-poly dielectric on a side adjacent to a memory cell and no inter-poly dielectric on a side away from a memory cell. Gaps etched through such openings may also define peripheral devices.

Abstract: Memory devices having an increased effective channel length and/or improved TPD characteristics, and methods of making the memory devices are provided. The memory devices contain two or more memory cells on a semiconductor substrate and bit line dielectrics between the memory cells. The memory cell contains a charge trapping dielectric stack, a poly gate, a pair of pocket implant regions, and a pair of bit lines. The bit line can be formed by an implant process at a higher energy level and/or a higher concentration of dopants without suffering device short channel roll off issues because spacers at bit line sidewalls constrain the implant in narrower implant regions.

Abstract: Memory devices having an increased effective channel length and/or improved TPD characteristics, and methods of making the memory devices are provided. The memory devices contain two or more memory cells on a semiconductor substrate and bit line dielectrics between the memory cells. The bit line dielectrics can extend into the semiconductor. The memory cell contains a charge trapping dielectric stack, a poly gate, a pair of pocket implant regions, and a pair of bit lines. The bit line can be formed by an implant process at a higher energy level and/or a higher concentration of dopants without suffering device short channel roll off issues because spacers at bit line sidewalls constrain the implant in narrower implant regions.

Abstract: Memory devices having improved TPD characteristics and methods of making the memory devices are provided. The memory devices contain two or more memory cells on a semiconductor substrate and bit line openings containing a bit line dielectric between the memory cells. The memory cell contains a charge storage layer and a first poly gate. The bit line opening extends into the semiconductor substrate. By containing the bit line dielectric in the bit line openings that extend into the semiconductor substrate, the memory device can improve the electrical isolation between memory cells, thereby preventing and/or mitigating TPD.

Abstract: Memory devices having improved TPD characteristics and methods of making the memory devices are provided. The memory devices contain two or more memory cells on a semiconductor substrate and bit line openings containing a bit line dielectric between the memory cells. The memory cell contains a charge storage layer and a first poly gate. The bit line opening extends into the semiconductor substrate. By containing the bit line dielectric in the bit line openings that extend into the semiconductor substrate, the memory device can improve the electrical isolation between memory cells, thereby preventing and/or mitigating TPD.

Abstract: Memory devices having an increased effective channel length and/or improved TPD characteristics, and methods of making the memory devices are provided. The memory devices contain two or more memory cells on a semiconductor substrate and bit line dielectrics between the memory cells. The bit line dielectrics can extend into the semiconductor. The memory cell contains a charge trapping dielectric stack, a poly gate, a pair of pocket implant regions, and a pair of bit lines. The bit line can be formed by an implant process at a higher energy level and/or a higher concentration of dopants without suffering device short channel roll off issues because spacers at bit line sidewalls constrain the implant in narrower implant regions.

Abstract: Memory devices having an increased effective channel length and/or improved TPD characteristics, and methods of making the memory devices are provided. The memory devices contain two or more memory cells on a semiconductor substrate and bit line dielectrics between the memory cells. The memory cell contains a pair of first bit lines and a pair of second bit lines. The first and second bit lines can be formed by an implant process using first and second spacers that have different lateral lengths from each other. The spacers can be used to offset the implants, thereby controlling the lateral lengths of the bit lines.

Abstract: Memory devices having an increased effective channel length and/or improved TPD characteristics, and methods of making the memory devices are provided. The memory devices contain two or more memory cells on a semiconductor substrate and bit line dielectrics between the memory cells. The bit line dielectrics can extend into the semiconductor. The memory cell contains a charge trapping dielectric stack, a poly gate, a pair of pocket implant regions, and a pair of bit lines. The bit line can be formed by an implant process at a higher energy level and/or a higher concentration of dopants without suffering device short channel roll off issues because spacers at bit line sidewalls constrain the implant in narrower implant regions.

Abstract: Memory devices having improved TPD characteristics and methods of making the memory devices are provided. The memory devices contain two or more memory cells on a semiconductor substrate and bit line dielectrics between the memory cells. The bit line dielectrics can extend into the semiconductor. The memory cell contains one or more charge storage nodes, a first poly gate, a pair of first bit lines, and a pair of second bit lines. The second bit line can be formed at a higher energy level, a higher concentration of dopants, or a combination thereof compared to an energy level and a concentration of dopants of the first bit line.

Abstract: Memory devices having improved TPD characteristics and methods of making the memory devices are provided. The memory devices contain two or more memory cells on a semiconductor substrate and bit line dielectrics between the memory cells. The bit line dielectrics can extend into the semiconductor. The memory cell contains one or more charge storage nodes, a first poly gate, a pair of first bit lines, and a pair of second bit lines. The second bit line can be formed at a higher energy level, a higher concentration of dopants, or a combination thereof compared to an energy level and a concentration of dopants of the first bit line.