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Extract from the Register of European Patents

EP About this file: EP3994731

EP3994731 - METHOD OF FORMING SPLIT-GATE FLASH MEMORY CELL WITH SPACER DEFINED FLOATING GATE AND DISCRETELY FORMED POLYSILICON GATES [Right-click to bookmark this link]
StatusNo opposition filed within time limit
Status updated on  22.11.2024
Database last updated on 18.03.2026
FormerThe patent has been granted
Status updated on  15.12.2023
FormerGrant of patent is intended
Status updated on  24.09.2023
FormerExamination is in progress
Status updated on  23.12.2022
FormerRequest for examination was made
Status updated on  08.04.2022
FormerThe international publication has been made
Status updated on  15.01.2021
Formerunknown
Status updated on  18.04.2020
Most recent event   Tooltip26.12.2025Lapse of the patent in a contracting state
New state(s): TR		published on 28.01.2026  [2026/05]
Applicant(s)For all designated states
Silicon Storage Technology Inc.
450 Holger Way
San Jose CA 95134 / US
[2022/19]
Inventor(s)01 / WANG, Chunming
Room 402, No. 16, Lane 238 Huoxiang Road
Shanghai 201203 / CN
02 / LIU, Xian
1236 Sargent Dr.
Sunnyvale, California 94087 / US
03 / DO, Nhan
20451 Walnut Avenue
Saratoga, California 95070 / US
04 / XING, Leo
No. 18 Lane 2277 Zuchongzhi Road
Shanghai 201210 / CN
05 / LIU, Guo Yong
No. 18 Lane 2277 Zuchongzhi Road
Shanghai 201210 / CN
06 / DIAO, Melvin
No. 18 Lane 2277 Zuchongzhi Road
Shanghai 201210 / CN
 [2022/19]
Representative(s)Betten & Resch
Patent- und Rechtsanwälte PartGmbB
Maximiliansplatz 14
80333 München / DE
[2022/19]
Application number, filing date20717381.606.03.2020
[2022/19]
WO2020US21454
Priority number, dateCN20191059833904.07.2019         Original published format: CN201910598339
US20201679641220.02.2020         Original published format: US202016796412
[2022/19]
Filing languageEN
Procedural languageEN
PublicationType: A1 Application with search report
No.:WO2021002892
Date:07.01.2021
Language:EN
[2021/01]
Type: A1 Application with search report 
No.:EP3994731
Date:11.05.2022
Language:EN
The application published by WIPO in one of the EPO official languages on 07.01.2021 takes the place of the publication of the European patent application.
[2022/19]
Type: B1 Patent specification 
No.:EP3994731
Date:17.01.2024
Language:EN
[2024/03]
Search report(s)International search report - published on:EP07.01.2021
ClassificationIPC:H01L29/423, H01L29/66, H01L29/788, H10B41/30
[2023/42]
CPC:
H10D30/6892 (EP,CN,KR); H10B41/30 (EP,CN,KR,US); H10D30/0411 (EP,CN,KR);
H10D64/035 (US); H10D30/685 (EP,CN,KR); H10P50/71 (US);
H10P52/403 (US) (-)
Former IPC [2022/19]H01L29/423, H01L27/11521, H01L29/66, H01L29/788
Designated contracting statesAL,   AT,   BE,   BG,   CH,   CY,   CZ,   DE,   DK,   EE,   ES,   FI,   FR,   GB,   GR,   HR,   HU,   IE,   IS,   IT,   LI,   LT,   LU,   LV,   MC,   MK,   MT,   NL,   NO,   PL,   PT,   RO,   RS,   SE,   SI,   SK,   SM,   TR [2022/19]
Extension statesBANot yet paid
MENot yet paid
Validation statesKHNot yet paid
MANot yet paid
MDNot yet paid
TNNot yet paid
TitleGerman:VERFAHREN ZUR HERSTELLUNG EINER SPLIT-GATE-FLASH-SPEICHERZELLE MIT EINEM DURCH EINEN ABSTANDSHALTER DEFINIERTEN SCHWEBENDEN GATE UND DISKRET GEFORMTEN POLYSILIZIUM-GATES[2022/19]
English:METHOD OF FORMING SPLIT-GATE FLASH MEMORY CELL WITH SPACER DEFINED FLOATING GATE AND DISCRETELY FORMED POLYSILICON GATES[2022/19]
French:PROCÉDÉ DE FORMATION D'UNE CELLULE DE MÉMOIRE FLASH À GRILLE DIVISÉE AVEC GRILLE FLOTTANTE DÉFINIE PAR ESPACEUR ET GRILLES DE POLYSILICIUM FORMÉES DE MANIÈRE DISCRÈTE[2022/19]
Entry into regional phase03.02.2022National basic fee paid 
03.02.2022Designation fee(s) paid 
03.02.2022Examination fee paid 
Examination procedure03.02.2022Examination requested  [2022/19]
03.02.2022Date on which the examining division has become responsible
12.08.2022Amendment by applicant (claims and/or description)
03.01.2023Despatch of a communication from the examining division (Time limit: M06)
03.07.2023Reply to a communication from the examining division
25.09.2023Communication of intention to grant the patent
07.12.2023Fee for grant paid
07.12.2023Fee for publishing/printing paid
07.12.2023Receipt of the translation of the claim(s)
Opposition(s)18.10.2024No opposition filed within time limit [2024/52]
Fees paidRenewal fee
23.03.2022Renewal fee patent year 03
21.03.2023Renewal fee patent year 04
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Responsibility for the accuracy, completeness or quality of the data displayed under the link provided lies entirely with the Unified Patent Court.
Lapses during opposition  TooltipCY06.03.2020
HU06.03.2020
AT17.01.2024
BG17.01.2024
CZ17.01.2024
DK17.01.2024
EE17.01.2024
ES17.01.2024
FI17.01.2024
HR17.01.2024
IT17.01.2024
LT17.01.2024
LV17.01.2024
MC17.01.2024
PL17.01.2024
RO17.01.2024
SE17.01.2024
SI17.01.2024
SK17.01.2024
SM17.01.2024
TR17.01.2024
IE06.03.2024
LU06.03.2024
BE31.03.2024
CH31.03.2024
GB17.04.2024
NO17.04.2024
RS17.04.2024
GR18.04.2024
IS17.05.2024
PT17.05.2024
[2026/05]
Former [2025/41]CY06.03.2020
HU06.03.2020
AT17.01.2024
BG17.01.2024
CZ17.01.2024
DK17.01.2024
EE17.01.2024
ES17.01.2024
FI17.01.2024
HR17.01.2024
IT17.01.2024
LT17.01.2024
LV17.01.2024
MC17.01.2024
PL17.01.2024
RO17.01.2024
SE17.01.2024
SI17.01.2024
SK17.01.2024
SM17.01.2024
IE06.03.2024
LU06.03.2024
BE31.03.2024
CH31.03.2024
GB17.04.2024
NO17.04.2024
RS17.04.2024
GR18.04.2024
IS17.05.2024
PT17.05.2024
Former [2025/37]CY06.03.2020
AT17.01.2024
BG17.01.2024
CZ17.01.2024
DK17.01.2024
EE17.01.2024
ES17.01.2024
FI17.01.2024
HR17.01.2024
IT17.01.2024
LT17.01.2024
LV17.01.2024
MC17.01.2024
PL17.01.2024
RO17.01.2024
SE17.01.2024
SI17.01.2024
SK17.01.2024
SM17.01.2024
IE06.03.2024
LU06.03.2024
BE31.03.2024
CH31.03.2024
GB17.04.2024
NO17.04.2024
RS17.04.2024
GR18.04.2024
IS17.05.2024
PT17.05.2024
Former [2025/22]AT17.01.2024
BG17.01.2024
CZ17.01.2024
DK17.01.2024
EE17.01.2024
ES17.01.2024
FI17.01.2024
HR17.01.2024
IT17.01.2024
LT17.01.2024
LV17.01.2024
MC17.01.2024
PL17.01.2024
RO17.01.2024
SE17.01.2024
SI17.01.2024
SK17.01.2024
SM17.01.2024
IE06.03.2024
LU06.03.2024
BE31.03.2024
CH31.03.2024
GB17.04.2024
NO17.04.2024
RS17.04.2024
GR18.04.2024
IS17.05.2024
PT17.05.2024
Former [2025/11]AT17.01.2024
BG17.01.2024
CZ17.01.2024
DK17.01.2024
EE17.01.2024
ES17.01.2024
FI17.01.2024
HR17.01.2024
IT17.01.2024
LT17.01.2024
LV17.01.2024
MC17.01.2024
PL17.01.2024
RO17.01.2024
SE17.01.2024
SK17.01.2024
SM17.01.2024
IE06.03.2024
LU06.03.2024
BE31.03.2024
CH31.03.2024
GB17.04.2024
NO17.04.2024
RS17.04.2024
GR18.04.2024
IS17.05.2024
PT17.05.2024
Former [2025/10]AT17.01.2024
BG17.01.2024
CZ17.01.2024
DK17.01.2024
EE17.01.2024
ES17.01.2024
FI17.01.2024
HR17.01.2024
IT17.01.2024
LT17.01.2024
LV17.01.2024
MC17.01.2024
PL17.01.2024
RO17.01.2024
SE17.01.2024
SK17.01.2024
SM17.01.2024
IE06.03.2024
LU06.03.2024
BE31.03.2024
GB17.04.2024
NO17.04.2024
RS17.04.2024
GR18.04.2024
IS17.05.2024
PT17.05.2024
Former [2025/09]AT17.01.2024
BG17.01.2024
CZ17.01.2024
DK17.01.2024
EE17.01.2024
ES17.01.2024
FI17.01.2024
HR17.01.2024
IT17.01.2024
LT17.01.2024
LV17.01.2024
MC17.01.2024
PL17.01.2024
RO17.01.2024
SE17.01.2024
SK17.01.2024
SM17.01.2024
LU06.03.2024
BE31.03.2024
GB17.04.2024
NO17.04.2024
RS17.04.2024
GR18.04.2024
IS17.05.2024
PT17.05.2024
Former [2025/08]AT17.01.2024
BG17.01.2024
CZ17.01.2024
DK17.01.2024
EE17.01.2024
ES17.01.2024
FI17.01.2024
HR17.01.2024
IT17.01.2024
LT17.01.2024
LV17.01.2024
MC17.01.2024
PL17.01.2024
RO17.01.2024
SE17.01.2024
SK17.01.2024
SM17.01.2024
LU06.03.2024
BE31.03.2024
NO17.04.2024
RS17.04.2024
GR18.04.2024
IS17.05.2024
PT17.05.2024
Former [2025/02]AT17.01.2024
BG17.01.2024
CZ17.01.2024
DK17.01.2024
EE17.01.2024
ES17.01.2024
FI17.01.2024
HR17.01.2024
IT17.01.2024
LT17.01.2024
LV17.01.2024
MC17.01.2024
PL17.01.2024
RO17.01.2024
SE17.01.2024
SK17.01.2024
SM17.01.2024
LU06.03.2024
NO17.04.2024
RS17.04.2024
GR18.04.2024
IS17.05.2024
PT17.05.2024
Former [2024/52]AT17.01.2024
BG17.01.2024
CZ17.01.2024
DK17.01.2024
EE17.01.2024
ES17.01.2024
FI17.01.2024
HR17.01.2024
LT17.01.2024
LV17.01.2024
MC17.01.2024
PL17.01.2024
RO17.01.2024
SE17.01.2024
SK17.01.2024
SM17.01.2024
LU06.03.2024
NO17.04.2024
RS17.04.2024
GR18.04.2024
IS17.05.2024
PT17.05.2024
Former [2024/49]AT17.01.2024
BG17.01.2024
CZ17.01.2024
DK17.01.2024
EE17.01.2024
ES17.01.2024
FI17.01.2024
HR17.01.2024
LT17.01.2024
LV17.01.2024
PL17.01.2024
RO17.01.2024
SE17.01.2024
SK17.01.2024
SM17.01.2024
NO17.04.2024
RS17.04.2024
GR18.04.2024
IS17.05.2024
PT17.05.2024
Former [2024/48]AT17.01.2024
BG17.01.2024
CZ17.01.2024
DK17.01.2024
EE17.01.2024
ES17.01.2024
FI17.01.2024
HR17.01.2024
LT17.01.2024
LV17.01.2024
PL17.01.2024
SE17.01.2024
SM17.01.2024
NO17.04.2024
RS17.04.2024
GR18.04.2024
IS17.05.2024
PT17.05.2024
Former [2024/47]AT17.01.2024
BG17.01.2024
DK17.01.2024
ES17.01.2024
FI17.01.2024
HR17.01.2024
LT17.01.2024
LV17.01.2024
PL17.01.2024
SE17.01.2024
SM17.01.2024
NO17.04.2024
RS17.04.2024
GR18.04.2024
IS17.05.2024
PT17.05.2024
Former [2024/37]AT17.01.2024
BG17.01.2024
ES17.01.2024
FI17.01.2024
HR17.01.2024
LT17.01.2024
LV17.01.2024
PL17.01.2024
SE17.01.2024
NO17.04.2024
RS17.04.2024
GR18.04.2024
IS17.05.2024
PT17.05.2024
Former [2024/36]AT17.01.2024
BG17.01.2024
ES17.01.2024
FI17.01.2024
HR17.01.2024
LT17.01.2024
LV17.01.2024
PL17.01.2024
NO17.04.2024
RS17.04.2024
GR18.04.2024
IS17.05.2024
PT17.05.2024
Former [2024/35]AT17.01.2024
BG17.01.2024
ES17.01.2024
FI17.01.2024
HR17.01.2024
LT17.01.2024
NO17.04.2024
RS17.04.2024
GR18.04.2024
IS17.05.2024
Former [2024/34]BG17.01.2024
FI17.01.2024
HR17.01.2024
LT17.01.2024
NO17.04.2024
RS17.04.2024
GR18.04.2024
IS17.05.2024
Former [2024/33]LT17.01.2024
NO17.04.2024
IS17.05.2024
Former [2024/32]IS17.05.2024
Cited inInternational search[XI] US9190532  (WANG CHUNMING et al.)
 [XI] US2008099789  (KOTOV ALEXANDER et al.) [X] 1-6,8 * paragraphs [0015] - [0021]; figures 2-9 *[I] 9,11,12
 [XI] US2016336415  (WU CHANG-MING et al.) [X] 1,7 * paragraphs [0028] - [0037]; figures 2A-2K *[I] 10
 [A] WO2017184315  (SILICON STORAGE TECH INC et al.) [A] 1 * paragraphs [0059] - [0077]; figures 10-20 *
by applicantUS7315056
The EPO accepts no responsibility for the accuracy of data originating from other authorities; in particular, it does not guarantee that it is complete, up to date or fit for specific purposes.