Invention Grant
- Patent Title: Three-dimensional memory device with double-sided stepped surfaces and method of making thereof
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Application No.: US16985305Application Date: 2020-08-05
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Publication No.: US11569259B2Publication Date: 2023-01-31
- Inventor: Yuki Mizutani , Masaaki Higashitani
- Applicant: SANDISK TECHNOLOGIES LLC
- Applicant Address: US TX Addison
- Assignee: SANDISK TECHNOLOGIES LLC
- Current Assignee: SANDISK TECHNOLOGIES LLC
- Current Assignee Address: US TX Addison
- Agency: The Marbury Law Group PLLC
- Main IPC: H01L27/11582
- IPC: H01L27/11582 ; H01L23/528 ; H01L27/11565 ; H01L23/522 ; H01L27/1157

Abstract:
A memory die can include an alternating stack of insulating layers and electrically conductive layers located over a substrate, and memory stack structures vertically extending through the alternating stack. A first layer stack within the alternating stack includes a first staircase region in which the first electrically conductive layers have respective lateral extents that increase with a vertical distance from the substrate to provide first stepped surfaces. A second layer stack within the alternating stack includes a second staircase region in which the second electrically conductive layers have respective lateral extents that decrease with the vertical distance from the substrate to provide second stepped surfaces. The second layer stack can be more distal from the substrate than the first layer stack. Contact via structures can be formed from the top side and the bottom side of the alternating stack.
Information query
IPC分类: