Three-dimensional memory cells

• US 7,442,997 B2
• Filed: 09/07/2006
• Issued: 10/28/2008
• Est. Priority Date: 08/28/2002
• Status: Expired due to Fees

• Current Assignee: Guobiao Zhang
• Original Assignee: Guobiao Zhang
• Inventors: Zhang, Guobiao
• Primary Examiner(s): NGO, NGAN V
• Application Number:
  US11/309,656
• Publication Number:
  US 20070170520A1
• Time in Patent Office: 782 Days
• Field of Search: 257/183, 257/390, 257/E27.102, 257/E27.103, 257/E21.677
• US Class Current: 257/390
• CPC Class Codes: G11C 17/06 using diode elements G11C17/14 takes precedence
• CPC Class Codes: G11C 17/14 in which contents are determined by selectively establishing, breaking or modifying connecting links by permanently altering the state of coupling elements, e.g. PROM
• CPC Class Codes: G11C 5/063 Voltage and signal distribution in integrated semi-conductor memory access lines, e.g. word-line, bit-line, cross-over resistance, propagation delay
• CPC Class Codes: H01L 21/8221 Three dimensional integrated circuits stacked in different levels
• CPC Class Codes: H01L 27/0688 Integrated circuits having a three-dimensional layout
• CPC Class Codes: H01L 27/105 including field-effect components
• CPC Class Codes: H01L 29/06 characterised by their shape; characterised by the shapes, relative sizes, or dispositions of the semiconductor regions ; characterised by the concentration or distribution of impurities within semiconductor regions
• CPC Class Codes: H01L 29/76 Unipolar devices , e.g. field effect transistors
• CPC Class Codes: H10B 20/00 Read-only memory [ROM] devices
• CPC Class Codes: H10B 20/20 Programmable ROM [PROM] devices comprising field-effect components H10B20/10 takes precedence
• CPC Class Codes: H10B 20/50 having transistors on different levels, e.g. 3D ROM
• CPC Class Codes: H10B 20/65 of memory structures of the ROM only type
• CPC Class Codes: H10B 41/20 characterised by three-dimensional arrangements, e.g. with cells on different height levels
• CPC Class Codes: H10B 41/30 characterised by the memory core region
• CPC Class Codes: H10B 69/00 Erasable-and-programmable ROM [EPROM] devices not provided for in groups H10B41/00 - H10B63/00, e.g. ultraviolet erasable-and-programmable ROM [UVEPROM] devices

Abstract

The present invention discloses a three-dimensional memory (3D-M) with polarized 3D-ROM (three-dimensional read-only memory) cells. Polarized 3D-ROM can ensure a larger unit array and therefore, a better integratibility. The present invention further discloses a 3D-M with seamless 3D-ROM cells. Seamless 3D-ROM can ensure a better manufacturing yield.

Claims

1. A polarized 3D-ROM (three-dimensional read-only memory) cell, comprising:

first and second conductive layers; and

a polarized quasi-conductive layer between said first and second conductive layers, said polarized quasi-conductive layer comprising first and second sub-layers of different base materials;

whereby said polarized quasi-conductive layer has a lower resistance when the current flows in one direction than when the current flows in the opposite direction.

2. The polarized 3D-ROM cell according to claim 1, wherein said 3D-ROM is three-dimensional mask-programmable read-only memory (3D-MPROM).

3. The polarized 3D-ROM cell according to claim 1, wherein said 3D-ROM is three-dimensional electrically programmable read-only memory (3D-EPROM).

4. The polarized 3D-ROM cell according to claim 1, wherein the base material of said first sub-layer is a first semiconductor material, and the base material of said second sub-layer is a second semiconductor material different from said first semiconductor material.

5. The polarized 3D-ROM cell according to claim 4, wherein said first semiconductor material is Si, and said second semiconductor material is selected from a group consisting of Ge, Si_yGe_1-y (0≦

y≦

1), C, and Si_zC_1-z(0≦

z≦

1).

6. The polarized 3D-ROM cell according to claim 1, wherein the base material of said first sub-layer is a semiconductor material, and the base material of said second sub-layer is a dielectric material.

7. The polarized 3D-ROM cell according to claim 1, wherein the base material of said first sub-layer is a first dielectric material, and the base material of said second sub-layer is a second dielectric material different from said first dielectric material.

8. The polarized 3D-ROM cell according to claim 1, wherein said first sub-layer has a first material structure, and said second sub-layer has a second material structure different from said first material structure.