Semiconductor memory device having integrated DOSRAM and NOSRAM

Patent metadata

Field	Value
Publication number	US-9564217-B1
Application number	US-201514886116-A
Country	US
Kind code	B1
Filing date	Oct 19, 2015
Priority date	Oct 19, 2015
Publication date	Feb 7, 2017
Grant date	Feb 7, 2017

Abstract

A semiconductor memory device includes a semiconductor substrate having a main surface, at least a first dielectric layer on the main surface of the semiconductor substrate, a first OS FET device and a second OS FET device disposed on the first dielectric layer, at least a second dielectric layer covering the first dielectric layer, the first OS FET device, and the second OS FET device, a first MIM capacitor on the second dielectric layer and electrically coupled to the first OS FET device, and a second MIM capacitor on the second dielectric layer and electrically coupled to the second OS FET device.

First claim

What is claimed is:

1. A semiconductor memory device, comprising:
a semiconductor substrate having a main surface;
at least a first dielectric layer on the main surface of the semiconductor substrate;
a first oxide semiconductor field effect transistor (OS FET) device disposed on the first dielectric layer;
a second OS FET device disposed on the first dielectric layer;
at least a second dielectric layer covering the first dielectric layer, the first OS FET device, and the second OS FET device;
a first metal-insulator-metal (MIM) capacitor on the second dielectric layer and electrically coupled to the first OS FET device, thereby constituting a dynamic oxide semiconductor random access memory (DOSRAM) cell, wherein the first MIM capacitor comprises a first bottom plate (BP) in a first capacitor trench, a first high-k dielectric layer on the first BP, and a first top plate (TP) on the first high-k dielectric layer; and
a second MIM capacitor on the second dielectric layer and electrically coupled to the second OS FET device, thereby constituting a non-volatile oxide semiconductor random access memory (NOSRAM) cell.

2. The semiconductor memory device of claim 1 , wherein the first OS FET device or the second OS FET device comprises a gate electrode, a source electrode, and a drain electrode, wherein the gate electrode traverses a channel material layer.

3. The semiconductor memory device of claim 2 , wherein the channel material layer comprises an oxide semiconductor (OS) material layer, wherein the oxide semiconductor material layer comprises In—Ga—Zn oxide (IGZO) or c-axis aligned crystalline oxide semiconductor (CAAC-OS) materials.

4. The semiconductor memory device of claim 1 further comprising at least a metal-oxide-semiconductor field-effect-transistor (MOS FET) device disposed on and in the main surface of the semiconductor substrate.

5. The semiconductor memory device of claim 1 , wherein the high-k dielectric layer comprises Al 2 O 3 , HfO x , ZrO x , BaTiO x , or ZrO 2 —Al 2 O 3 —ZrO 2 (ZAZ).

6. The semiconductor memory device of claim 1 , wherein the second MIM capacitor comprises a second BP on the second dielectric layer, a low-leakage dielectric layer on the second BP, and a second TP on the low-leakage dielectric layer.

7. The semiconductor memory device of claim 6 , wherein the low-leakage dielectric layer comprises SiO 2 , SiON, SiN, or ONO.

8. The semiconductor memory device of claim 6 , wherein the second BP comprises an electrically floating first metal layer, a second high-k dielectric layer on the first metal layer, and a second metal layer on the second high-k dielectric layer.

9. The semiconductor memory device of claim 6 , wherein the second BP is disposed in a second capacitor trench.

Assignees

• United Microelectronics Corp

Inventors

• Zhou Zhibiao
• Lin Chen-Bin
• Ku Chi-Fa
• Wu shao-hui

Classifications

• H10P14/69433

  the material being a silicon nitride not containing oxygen, e.g. SixNy or SixByNz · CPC title

• H10P14/69397

  the material containing two or more metal elements · CPC title

• H10P14/69395

  the material containing zirconium, e.g. ZrO2 · CPC title

• H10P14/69392

  the material containing hafnium, e.g. HfO2 · CPC title

• H10P14/69391

  the material containing aluminium, e.g. Al2O3 · CPC title