PATENT CLAIM ANALYSIS

Application Number: 16435887
Application Type: Utility
Filing Date: 2019-06
Publication Date: 2019-09
Patent Classification: ["438", "268000"]

Abstract:
Methods of forming 3-d flash memory cells are described. The methods allow the cells to be produced despite a misalignment in at least two sections (top and bottom), each having multiple charge storage locations. The methods include selectively gas-phase etching dielectric from the bottom memory hole portion by delivering the etchants through the top memory hole. Two options for completing the methods include (1) forming a ledge spacer to allow reactive ion etching of the bottom polysilicon portion without damaging polysilicon or charge-trap/ONO layer on the ledge, and (2) placing sacrificial silicon oxide gapfill in the bottom memory hole, selectively forming protective conformal silicon nitride elsewhere, then removing the sacrificial silicon oxide gapfill before performing the reactive ion etching of the bottom polysilicon portion as before.

Claim (Index 1):
A method of forming a memory cell, the method comprising:\n forming a silicon nitride spacer on a ledge of a patterned substrate positioned in a substrate processing chamber, wherein the patterned substrate comprises a vertical stack of alternating oxide and nitride layers defining a vertical memory hole there through, wherein sidewalls of the vertical memory hole include a conformal coating and a first polysilicon layer overlying the conformal coating, and wherein the vertical stack comprises a bottom portion and a top portion laterally misaligned to form the ledge; removing a bottom portion of the first polysilicon layer by reactive ion etching the bottom portion of the first polysilicon layer while retaining sidewall portions of the first polysilicon layer; removing a bottom portion of the conformal coating using a gas-phase etch; removing the silicon nitride spacer from the ledge using a gas-phase etch; and forming a second polysilicon layer on the first polysilicon layer.

Metadata:
- Claim Count in Document: 47.0
- Percentile: 100.0
- Lexical Diversity: 1.75
- Patent Class: 438.0
- Transitional Phrase Type: open
- Component Type: 1
- Foreign Priority: False
- Related Applications: ['15882454', '15891126', '14452220', '15332910', '14222418']

Analysis Scores:
- 35 USC 101 Eligibility (BERT): 0.9069013440590986
- 35 USC 102 Novelty (BERT): 0.5677337031081253
- Combined Prediction Score: 0.8729845799640013
- Mean Citation Score: 367.319006
- Max Citation Score: 460.03082
- Similarity Product: 389.442869011748

Labels:
- Claim Label 101: 1
- Claim Label 102: 1
- Claim Label 103: 1
- Claim Label 112: 1
- Combined Label: 1
- Label 101 Adjusted: 1

Dataset: test