Three-dimensional memory device containing CMOS devices over memory stack structures

Patent metadata

Field	Value
Publication number	US-9530790-B1
Application number	US-201514757572-A
Country	US
Kind code	B1
Filing date	Dec 24, 2015
Priority date	Dec 24, 2015
Publication date	Dec 27, 2016
Grant date	Dec 27, 2016

Abstract

Peripheral devices for a three-dimensional memory device can be formed over an array of memory stack structures to increase areal efficiency of a semiconductor chip. First contact via structures and first metal lines are formed over an array of memory stack structures and an alternating stack of insulating layers and electrically conductive layers. A semiconductor material layer including a single crystalline semiconductor material or a polycrystalline semiconductor material is formed over first metal lines. After formation of semiconductor devices on or in the semiconductor material layer, metal interconnect structures including second metal lines and additional conductive via structures are formed to electrically connect nodes of the semiconductor devices to respective first metal lines and to memory devices underneath.

First claim

What is claimed is:

1. A three-dimensional semiconductor structure, comprising:
an alternating stack of insulating layers and electrically conductive layers located over a substrate;
an array of memory stack structures that extend through the alternating stack, each of the memory stack structures comprising a plurality of memory elements surrounding a semiconductor channel;
a first metal interconnect structure overlying the alternating stack and comprising first dielectric material layers, first metal lines embedded within the first dielectric material layers, and first contact via structures contacting a bottom surface of a respective first metal line and electrically shorted to a respective element selected from nodes of the memory stack structures and the electrically conductive layers;
a semiconductor material layer overlying the first metal interconnect structure; and
at least one semiconductor device located on or in the semiconductor material layer and electrically connected to the first metal lines.

2. The three-dimensional semiconductor structure of claim 1 , further comprising:
a doped drain region located over an end portion of the semiconductor channel;
a doped source region located in or on the substrate;
a backside trench extending through the alternating stack; and
a source contact via structure located the backside trench and contacting the doped source region.

3. The three-dimensional semiconductor structure of claim 2 , wherein the at least one semiconductor device is located within a same area as the array of the memory stack structures in a plan view.

4. The three-dimensional semiconductor structure of claim 2 , further comprising:
a second metal interconnect structure overlying the first metal interconnect structure and comprising at least one second dielectric material layer that overlies the semiconductor material layer;
second metal lines embedded within the at least one second dielectric material layer;
second contact via structures electrically shorted to a respective second metal line and to a respective first metal line;
third contact via structures electrically shorted to a respective second metal line and to a respective node of the at least one semiconductor device; and
insulating spacers laterally surrounding a respective second contact via structure and electrically isolating the respective second contact via structure from the semiconductor material layer.

5. The three-dimensional semiconductor structure of claim 1 , wherein the at least one semiconductor device comprises a metal-oxide-semiconductor (MOS) field effect transistor.

6. The three-dimensional semiconductor structure of claim 5 , wherein:
the semiconductor structure comprises a vertical NAND memory device; and
the MOS field effect transistor is located in a CMOS device which comprises at least a portion of bit line driver for accessing bit lines for the memory stack structures, a word line driver for accessing control gate electrodes embodied as the electrically conductive layers, a source select gate driver for accessing a source node for the memory stack structures, or a drain select gate driver for accessing a drain node for the memory stack structures.

7. The three-dimensional semiconductor structure of claim 1 , wherein the first metal lines comprise:
bit lines electrically shorted to an end portion of a respective semiconductor channel; and
word lines electrically shorted to a respective electrically conductive layer among the electrically conductive layers.

8. The three-dimensional semiconductor structure of claim 1 , further comprising additional semiconductor devices located on or in a substrate semiconductor material layer within the substrate.

9. The three-dimensional semiconductor structure of claim 1 , wherein:
the semiconductor material layer is a single-crystalline semiconductor material layer; and
the at least one semiconductor device comprises a metal-oxide-semiconductor (MOS) field effect transistor including a portion of the single-crystalline semiconductor material layer as a channel.

10. The three-dimensional semiconductor structure of claim 1 , wherein:
the semiconductor material layer is a polycrystalline semiconductor material layer; and
the at least one semiconductor device comprises a metal-oxide-semiconductor (MOS) thin film transistor including a portion of the polycrystalline semiconductor material layer as a channel.

11. The three-dimensional semiconductor structure of claim 1 , wherein each of the memory stack structure comprises:
a tunneling dielectric laterally surrounding a respective semiconductor channel;
a vertical stack of charge storage regions laterally surrounding the tunneling dielectric layer; and
a blocking dielectric disposed between the vertical stack of charge storage regions and the electrically conductive layers.

12. The three-dimensional semiconductor structure of claim 11 , wherein:
the three-dimensional semiconductor structure comprises a vertical NAND device formed in a device region;
the electrically conductive layers comprise, or are electrically connected to, a respective word line of the NAND device;
the device region comprises:
a plurality of semiconductor channels, wherein at least one end portion of each of the plurality of semiconductor channels extends substantially perpendicular to a top surface of the substrate;
a plurality of charge storage regions, each charge storage region located adjacent to a respective one of the plurality of semiconductor channels; and
a plurality of control gate electrodes having a strip shape extending substantially parallel to the top surface of the substrate;

the plurality of control gate electrodes comprise at least a first control gate electrode located in a first device level and a second control gate electrode located in a second device level;
the electrically conductive layers in the alternating stack are in electrical contact with the plurality of control gate electrodes and extend from the device region to a contact region including a plurality of electrically conductive via connections; and
the substrate comprises a silicon substrate.

13. A method of forming a three-dimensional semiconductor device, comprising:
forming an alternating stack of insulating layers and spacer material layers over a substrate;
forming an array of memory stack structures that extend through the alternating stack, each of the memory stack structures comprising a plurality of memory elements surrounding a semiconductor channel, wherein the spacer material layers are formed as, or are replaced with, electrically conductive layers;
forming a first metal interconnect structure, wherein the first metal interconnect structure comprises first dielectric material layers overlying the alternating stack, first metal lines embedded within the first dielectric material layers, and first contact via structures contacting a bottom surface of a respective first metal line and electrically shorted to a respective element selected from nodes of the memory stack structures and the electrically conductive layers;
forming a semiconductor material layer over the metal interconnect structure;
forming at least one semiconductor device on or in the semiconductor material layer; and
electrically connecting the at least one semiconductor device to the first metal lines.

14. The method of claim 13 , further comprising:
forming a doped drain region over an end portion of the semiconductor channel;
forming backside trench extending through the alternating stack;
forming a doped source region in or on the substrate through the backsid

Assignees

• Sandisk Technologies Inc
• Sandisk Technologies Llc

Inventors

• Lu Zhenyu
• Lin Andrew
• Alsmeier Johann
• Rabkin Peter
• Zhao Wei
• Shi Wenguang Stephen
• Chien Henry
• Chen Jian

Classifications

• H10D88/00 Primary

  Three-dimensional [3D] integrated devices · CPC title

• H10D30/6745

  Polycrystalline or microcrystalline silicon · CPC title

• H10D30/683

  programmed by tunnelling of carriers, e.g. Fowler-Nordheim tunnelling · CPC title

• H01L27/11526

  Electricity · mapped topic

• H01L23/528

  Electricity · mapped topic