US20010009289A1 - Flash memory device and fabrication method thereof - Google Patents
Flash memory device and fabrication method thereof Download PDFInfo
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- US20010009289A1 US20010009289A1 US09/798,961 US79896101A US2001009289A1 US 20010009289 A1 US20010009289 A1 US 20010009289A1 US 79896101 A US79896101 A US 79896101A US 2001009289 A1 US2001009289 A1 US 2001009289A1
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- 238000000034 method Methods 0.000 title claims abstract description 32
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 12
- 238000009413 insulation Methods 0.000 claims abstract description 82
- 239000000758 substrate Substances 0.000 claims abstract description 38
- 125000006850 spacer group Chemical group 0.000 claims abstract description 21
- 239000012535 impurity Substances 0.000 claims description 20
- 150000004767 nitrides Chemical class 0.000 claims description 14
- 229910021420 polycrystalline silicon Inorganic materials 0.000 claims 2
- 229920005591 polysilicon Polymers 0.000 claims 2
- 239000004065 semiconductor Substances 0.000 abstract description 25
- 239000010410 layer Substances 0.000 description 74
- 230000005684 electric field Effects 0.000 description 6
- 230000005641 tunneling Effects 0.000 description 6
- 230000000694 effects Effects 0.000 description 4
- 230000007423 decrease Effects 0.000 description 3
- 238000005229 chemical vapour deposition Methods 0.000 description 2
- 230000003247 decreasing effect Effects 0.000 description 2
- 239000011229 interlayer Substances 0.000 description 2
- 238000005530 etching Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices adapted for rectifying, amplifying, oscillating or switching, or capacitors or resistors with at least one potential-jump barrier or surface barrier, e.g. PN junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/40—Electrodes ; Multistep manufacturing processes therefor
- H01L29/41—Electrodes ; Multistep manufacturing processes therefor characterised by their shape, relative sizes or dispositions
- H01L29/423—Electrodes ; Multistep manufacturing processes therefor characterised by their shape, relative sizes or dispositions not carrying the current to be rectified, amplified or switched
- H01L29/42312—Gate electrodes for field effect devices
- H01L29/42316—Gate electrodes for field effect devices for field-effect transistors
- H01L29/4232—Gate electrodes for field effect devices for field-effect transistors with insulated gate
- H01L29/42324—Gate electrodes for transistors with a floating gate
- H01L29/42332—Gate electrodes for transistors with a floating gate with the floating gate formed by two or more non connected parts, e.g. multi-particles flating gate
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L27/00—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate
- H01L27/02—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier
- H01L27/04—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier the substrate being a semiconductor body
- H01L27/10—Devices consisting of a plurality of semiconductor or other solid-state components formed in or on a common substrate including semiconductor components specially adapted for rectifying, oscillating, amplifying or switching and having at least one potential-jump barrier or surface barrier; including integrated passive circuit elements with at least one potential-jump barrier or surface barrier the substrate being a semiconductor body including a plurality of individual components in a repetitive configuration
-
- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L29/00—Semiconductor devices adapted for rectifying, amplifying, oscillating or switching, or capacitors or resistors with at least one potential-jump barrier or surface barrier, e.g. PN junction depletion layer or carrier concentration layer; Details of semiconductor bodies or of electrodes thereof ; Multistep manufacturing processes therefor
- H01L29/40—Electrodes ; Multistep manufacturing processes therefor
- H01L29/401—Multistep manufacturing processes
- H01L29/4011—Multistep manufacturing processes for data storage electrodes
- H01L29/40114—Multistep manufacturing processes for data storage electrodes the electrodes comprising a conductor-insulator-conductor-insulator-semiconductor structure
Definitions
- the present invention relates to memory devices and, in particular, to a flash memory device and a fabrication method thereof
- FIG. 1 illustrates a related art Floating-gate Tunneling Oxide (FLOTOX Electrically Erasable and Programmable Read Only Memory (EEPROM).
- An active region 1 a and a field region 1 b are formed on the upper surface of a semiconductor substrate 1 .
- source and drain regions 2 and 3 are formed in the semiconductor substrate 1 .
- a gate insulation layer 4 and a tunnel insulation layer 5 are formed within the active region 1 a of the semiconductor substrate 1 .
- a first conductive layer (floating gate) 6 is formed on the upper surfaces of the gate insulation layer 4 and the tunnel insulation layer 5 .
- An interlayer insulation film 7 is formed on the upper surface of the first conductive layer 6 .
- a second conductive layer (control gate) 8 is formed on the upper surface of the interlayer insulation film 7 .
- An insulation film 9 is formed on the upper surfaces of the semiconductor substrate 1 and the second conductive layer 8 .
- Electrons are injected into the floating gate 6 from the drain 3 through the tunnel insulation layer 5 via a Folwer-Nordheim (FN) tunneling effect. Electrons accumulate in the floating gate 6 , the threshold voltage of the device increases, and the intensity of the electric field, which is applied from the control gate 8 to the drain 3 , increases.
- FN Folwer-Nordheim
- the source 2 and the semiconductor substrate 1 are connected to ground, zero volts is supplied to the control gate 8 and twenty volts are supplied to the drain 3 . Electrons accumulated in the floating gate 6 are moved into the drain region 3 through the tunnel insulation layer 5 via the FN tunneling effect. Since the number of electrons in the floating gate 6 decrease, the threshold voltage of the FLOTOX EEPROM decreases, and the intensity of the electric field, which is applied from the drain 3 to the control gate 8 , also decreases.
- the related art FLOTOX EEPROM requires a high voltage during programming and data erasing operations, and a high substrate current is generated due to the high voltage during data erasing operations. As a result, the characteristics of the FLOTOX EEPROM and the tunnel insulation layer 5 are quickly degraded.
- a flash memory device comprising: (1) a semiconductor substrate; (2) a source region and a drain region in the semiconductor substrate; (3) a first insulation layer formed on the semiconductor substrate; (4) a first conductive layer formed on a portion of the first insulation layer; ( 5 ) first and second conductive sidewall spacers positioned adjacent to first and second sidewalls of the first conductive layer, respectively; (6) a second insulation layer formed on the first and second sidewall conductive sidewall spacers; and (7) a second conductive layer formed on the insulation layer, the second conductive layer in electrical contact with the first conductive layer.
- a flash memory device fabrication method which comprises the steps of: (1) forming a first insulation layer on a semiconductor substrate; (2) forming a first conductive layer pattern on a portion of the first insulation layer; (3) forming low density impurity regions in the semiconductor substrate; (4) forming a second insulation layer on sidewalls of the first conductive layer pattern; (5) forming, on each of the sides of the first conductive layer pattern, a conductive sidewall spacer on the second insulation layer and the first insulation layer; (6) forming high density impurity regions in the semiconductor substrate; (7) forming a third insulation layer that covers the conductive sidewall spacers and that contacts the first and second insulation layers; and (8) forming a third conductive layer pattern on the first, second and third insulation layers, the third conductive layer pattern in electrical contact with the first conductive layer pattern.
- FIG. 1 is a horizontal cross-sectional view of related art floating-gate tunneling oxide (FLOTOX) EEPROM;
- FIG. 2 is a horizontal cross-sectional view of a flash memory device according to the present invention.
- FIG. 3 is a plan view of the flash memory device of FIG. 2;
- FIGS. 4A-4C are cross-sectional views illustrating process steps of a preferred method for fabricating a flash memory device according to the present invention.
- FIGS. 2 and 3 illustrate a flash memory device according to the present invention.
- the flash memory device according to the present invention comprises a semiconductor substrate 11 having an active region 11 a and field regions 11 b formed thereon, and source and drain regions 12 and 13 , respectively, defined in the semiconductor substrate 11 .
- the source region 12 and the drain region 13 include low density doping regions 12 a and 13 a , respectively, and high density doping regions 12 b and 13 b , respectively.
- a first insulation layer 14 is formed on the active region 11 a of the semiconductor substrate 11 .
- the first insulation layer 14 includes a gate insulation layer 14 a , and a tunnel insulation layer 14 b formed on the upper surfaces of the source and drain regions 12 and 13 .
- a first conductive layer (first control gate) 15 is formed on the upper surface of the gate insulation layer 14 a .
- Second conductive layer sidewall spacer (floating gate) 18 are formed on each sidewall of the first control gate 15 , and are covered by a second insulation layer (sidewall insulation layer) 16 and a third insulation layer (sidewall insulation layer) 17 .
- a third conductive layer pattern (second control gate) 19 is formed on the upper surfaces of the insulation layers 14 , 16 and 17 , and is connected with the first control gate 15 .
- an active region 11 a and a field region 1 lb are defined on the upper surface of the semiconductor substrate 11 , e.g., a P-type substrate, preferably by a LOCOS process.
- a first insulation layer (not shown) is deposited on the semiconductor substrate 11 , preferably by a CVD method, and a predetermined portion of the active region 11 a is patterned in order to form a gate insulation layer 14 a .
- a tunnel insulation layer 14 b is formed thinner than the thickness of the gate insulation layer 14 a .
- a first conductive layer (not shown) is deposited on the upper surface of the semiconductor substrate 11 including the gate insulation layer 14 a , preferably by a CVD method, and the resultant structure is patterned.
- the first conductive pattern (first control gate) 15 is then formed on the upper surface of the gate insulation layer 14 a.
- low density impurity regions (source/drain regions) 12 a and 13 a are formed, preferably by ion-implanting impurities into the semiconductor substrate 11 using the gate insulation layer 14 a and the first control gate 15 as a mask.
- a nitride film (not shown) is deposited on the semiconductor substrate 11 , including the first control gate 15 and the resultant structure is patterned.
- the nitride film pattern 20 is then formed by leaving the nitride film (not shown) on only the upper surface of the first control gate 15 .
- a second insulation layer (not shown) and a second conductive layer (not shown) are sequentially formed on the upper surface of the structure of FIG. 4A, including the nitride film pattern 20 , preferably by a CVD process.
- the second insulation layer and the second conductive layer are then dry-etched, and a sidewall insulation layer 16 and second conductive layer sidewall spacer (floating gate) 18 are formed by forming the second insulation layer (sidewall insulation layer) (not shown) and the second conductive layer (not shown) on the sidewall surfaces of the first control gate 15 and the nitride film pattern 20 .
- the upper surface of the nitride film pattern 20 is externally exposed.
- a high density of impurities are then ion-implanted into the semiconductor substrate 11 by using the nitride film pattern 20 and the floating gate 18 as a mask, thereby defining the source and drain regions 12 and 13 , respectively, having high density impurity regions neighboring with the low density impurity regions.
- the nitride film pattern 20 is etched, and a third insulation layer 17 is deposited on the upper surfaces of the first control gate 15 , the floating gate 18 , the first insulation layer 14 , and the second insulation layer 16 . Then, the portion of the third insulation layer 17 formed on the upper surface of the first control gate 15 is etched by using an etching mask. Thereafter, a third conductive layer (not shown) is deposited on the upper surfaces of the first control gate 15 and third insulation layer (sidewall insulation layer) 17 , preferably by a CVD process. The resultant structure is then patterned and connected with the first control gate 15 , thereby forming a third conductive layer pattern (second control gate) 19 . This completes the fabrication of the flash memory device structure according to the present invention.
- a positive low voltage is first supplied to the second control gate 19 , a negative low voltage is applied to the source and drain regions 12 and 13 , and the semiconductor substrate 11 is grounded. Based on the electrical field formed between the second control gate 19 and the source and drain 12 and 13 , electrons from the source and drain regions 12 and 13 are injected into each floating gate 18 through the tunnel insulation layer 14 b via the FN tunneling effect. When electrons have accumulated in the floating gate 18 , the threshold voltage of the flash memory device is increased, and the intensity of the electric field is increased.
- a negative low voltage is supplied to the second control gate 19 , a positive low voltage is supplied to the source and drain regions 12 and 13 , and the semiconductor substrate 11 is connected to ground.
- the electrical field formed between the source and drain regions 12 and 13 , and the second control gate 19 electrons accumulated in the floating gate 18 are injected into the source and drain regions 12 and 13 through the tunnel insulation layer 14 b via the FN tunneling effect.
- the number of electrons from the floating gate 18 is reduced, the threshold voltage of the flash memory device is decreased, and the intensity of the electric field is decreased.
- the flash memory device and fabrication method according to the present invention provide a flash memory which is capable of rapidly performing data erasure and programming operations at low voltage by forming a floating gate on both sidewalls of the control gate and on the low density impurity regions (source and drain), simplifying the fabrication process by using a self-aligning process, and controlling the size of the floating gate.
Abstract
A flash memory device and fabrication method simplify the fabrication process of a semiconductor EEPROM device through a self-aligning process. The device includes a semiconductor substrate in which source and drain regions are defined, a first insulation layer formed on the semiconductor substrate, a first conductive layer pattern formed on a portion of the first insulation layer, sidewall spacers formed of a second conductive layer neighboring each sidewall of the first conductive layer pattern and covered by second and third insulation layers, and a third conductive layer pattern formed on the insulation layers and connected with the first conductive layer pattern.
Description
- 1. Field of the Invention
- The present invention relates to memory devices and, in particular, to a flash memory device and a fabrication method thereof
- 2. Background of the Related Art
- FIG. 1 illustrates a related art Floating-gate Tunneling Oxide (FLOTOX Electrically Erasable and Programmable Read Only Memory (EEPROM). An active region1 a and a field region 1 b are formed on the upper surface of a
semiconductor substrate 1. In thesemiconductor substrate 1, source anddrain regions gate insulation layer 4 and atunnel insulation layer 5 are formed within the active region 1 a of thesemiconductor substrate 1. A first conductive layer (floating gate) 6 is formed on the upper surfaces of thegate insulation layer 4 and thetunnel insulation layer 5. Aninterlayer insulation film 7 is formed on the upper surface of the first conductive layer 6. A second conductive layer (control gate) 8 is formed on the upper surface of theinterlayer insulation film 7. Aninsulation film 9 is formed on the upper surfaces of thesemiconductor substrate 1 and the secondconductive layer 8. - In operation, twenty volts (20V) is supplied to the
control gate 8 and zero volts (0V) is supplied to thedrain 3. Thesource 2 and thesubstrate 1 are connected to ground. Electrons are injected into the floating gate 6 from thedrain 3 through thetunnel insulation layer 5 via a Folwer-Nordheim (FN) tunneling effect. Electrons accumulate in the floating gate 6, the threshold voltage of the device increases, and the intensity of the electric field, which is applied from thecontrol gate 8 to thedrain 3, increases. - To erase the data from the FLOTOX EEPROM, the
source 2 and thesemiconductor substrate 1 are connected to ground, zero volts is supplied to thecontrol gate 8 and twenty volts are supplied to thedrain 3. Electrons accumulated in the floating gate 6 are moved into thedrain region 3 through thetunnel insulation layer 5 via the FN tunneling effect. Since the number of electrons in the floating gate 6 decrease, the threshold voltage of the FLOTOX EEPROM decreases, and the intensity of the electric field, which is applied from thedrain 3 to thecontrol gate 8, also decreases. - The related art FLOTOX EEPROM requires a high voltage during programming and data erasing operations, and a high substrate current is generated due to the high voltage during data erasing operations. As a result, the characteristics of the FLOTOX EEPROM and the
tunnel insulation layer 5 are quickly degraded. - In addition, due to the high substrate current generated, it is not possible to erase the data in the related art FLOTOX EEPROM using a 5-volt power source. Furthermore, it is not possible to perform a self-aligning process during the fabrication process for the related art FLOTOX EEPROM.
- The above references are incorporated by reference herein where appropriate for appropriate teachings of additional or alternative details, features and/or technical background.
- Accordingly, it is an object of the present invention to provide a flash memory device and a flash memory fabrication method that overcome the aforementioned problems encountered in the related art.
- It is another object of the present invention to perform a data erasure at a low voltage.
- It is another object of the present invention to simplify the fabrication process of the memory device through a self-aligning process.
- To achieve the above objects, there is provided a flash memory device comprising: (1) a semiconductor substrate; (2) a source region and a drain region in the semiconductor substrate; (3) a first insulation layer formed on the semiconductor substrate; (4) a first conductive layer formed on a portion of the first insulation layer; (5) first and second conductive sidewall spacers positioned adjacent to first and second sidewalls of the first conductive layer, respectively; (6) a second insulation layer formed on the first and second sidewall conductive sidewall spacers; and (7) a second conductive layer formed on the insulation layer, the second conductive layer in electrical contact with the first conductive layer.
- To achieve the above objects, there is also provided a flash memory device fabrication method, which comprises the steps of: (1) forming a first insulation layer on a semiconductor substrate; (2) forming a first conductive layer pattern on a portion of the first insulation layer; (3) forming low density impurity regions in the semiconductor substrate; (4) forming a second insulation layer on sidewalls of the first conductive layer pattern; (5) forming, on each of the sides of the first conductive layer pattern, a conductive sidewall spacer on the second insulation layer and the first insulation layer; (6) forming high density impurity regions in the semiconductor substrate; (7) forming a third insulation layer that covers the conductive sidewall spacers and that contacts the first and second insulation layers; and (8) forming a third conductive layer pattern on the first, second and third insulation layers, the third conductive layer pattern in electrical contact with the first conductive layer pattern.
- Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objects and advantages of the invention may be realized and attained as particularly pointed out in the appended claims.
- The invention will be described in detail with reference to the following drawings in which like reference numerals refer to like elements wherein:
- FIG. 1 is a horizontal cross-sectional view of related art floating-gate tunneling oxide (FLOTOX) EEPROM;
- FIG. 2 is a horizontal cross-sectional view of a flash memory device according to the present invention;
- FIG. 3 is a plan view of the flash memory device of FIG. 2; and
- FIGS. 4A-4C are cross-sectional views illustrating process steps of a preferred method for fabricating a flash memory device according to the present invention.
- FIGS. 2 and 3 illustrate a flash memory device according to the present invention. As shown therein, the flash memory device according to the present invention comprises a
semiconductor substrate 11 having anactive region 11 a andfield regions 11 b formed thereon, and source anddrain regions semiconductor substrate 11. Thesource region 12 and thedrain region 13 include lowdensity doping regions density doping regions active region 11 a of thesemiconductor substrate 11. The first insulation layer 14 includes agate insulation layer 14 a, and atunnel insulation layer 14 b formed on the upper surfaces of the source anddrain regions - A first conductive layer (first control gate)15 is formed on the upper surface of the
gate insulation layer 14 a. Second conductive layer sidewall spacer (floating gate) 18 are formed on each sidewall of thefirst control gate 15, and are covered by a second insulation layer (sidewall insulation layer) 16 and a third insulation layer (sidewall insulation layer) 17. In addition, a third conductive layer pattern (second control gate) 19 is formed on the upper surfaces of theinsulation layers first control gate 15. - As shown in FIG. 4A, an
active region 11 a and afield region 1 lb are defined on the upper surface of thesemiconductor substrate 11, e.g., a P-type substrate, preferably by a LOCOS process. A first insulation layer (not shown) is deposited on thesemiconductor substrate 11, preferably by a CVD method, and a predetermined portion of theactive region 11 a is patterned in order to form agate insulation layer 14 a. On the remaining portions of theactive region 11 a, atunnel insulation layer 14 b is formed thinner than the thickness of thegate insulation layer 14 a. A first conductive layer (not shown) is deposited on the upper surface of thesemiconductor substrate 11 including thegate insulation layer 14 a, preferably by a CVD method, and the resultant structure is patterned. The first conductive pattern (first control gate) 15 is then formed on the upper surface of thegate insulation layer 14 a. - Thereafter, low density impurity regions (source/drain regions)12 a and 13 a are formed, preferably by ion-implanting impurities into the
semiconductor substrate 11 using thegate insulation layer 14a and thefirst control gate 15 as a mask. A nitride film (not shown) is deposited on thesemiconductor substrate 11, including thefirst control gate 15 and the resultant structure is patterned. Thenitride film pattern 20 is then formed by leaving the nitride film (not shown) on only the upper surface of thefirst control gate 15. - Referring to FIG. 4B, a second insulation layer (not shown) and a second conductive layer (not shown) are sequentially formed on the upper surface of the structure of FIG. 4A, including the
nitride film pattern 20, preferably by a CVD process. The second insulation layer and the second conductive layer are then dry-etched, and asidewall insulation layer 16 and second conductive layer sidewall spacer (floating gate) 18 are formed by forming the second insulation layer (sidewall insulation layer) (not shown) and the second conductive layer (not shown) on the sidewall surfaces of thefirst control gate 15 and thenitride film pattern 20. Next, the upper surface of thenitride film pattern 20 is externally exposed. A high density of impurities are then ion-implanted into thesemiconductor substrate 11 by using thenitride film pattern 20 and thefloating gate 18 as a mask, thereby defining the source anddrain regions - Referring to FIG. 4C, the
nitride film pattern 20 is etched, and athird insulation layer 17 is deposited on the upper surfaces of thefirst control gate 15, the floatinggate 18, the first insulation layer 14, and thesecond insulation layer 16. Then, the portion of thethird insulation layer 17 formed on the upper surface of thefirst control gate 15 is etched by using an etching mask. Thereafter, a third conductive layer (not shown) is deposited on the upper surfaces of thefirst control gate 15 and third insulation layer (sidewall insulation layer) 17, preferably by a CVD process. The resultant structure is then patterned and connected with thefirst control gate 15, thereby forming a third conductive layer pattern (second control gate) 19. This completes the fabrication of the flash memory device structure according to the present invention. - To program the flash memory device, a positive low voltage is first supplied to the
second control gate 19, a negative low voltage is applied to the source and drainregions semiconductor substrate 11 is grounded. Based on the electrical field formed between thesecond control gate 19 and the source and drain 12 and 13, electrons from the source and drainregions gate 18 through thetunnel insulation layer 14 b via the FN tunneling effect. When electrons have accumulated in the floatinggate 18, the threshold voltage of the flash memory device is increased, and the intensity of the electric field is increased. - During the data erasure operation, a negative low voltage is supplied to the
second control gate 19, a positive low voltage is supplied to the source and drainregions semiconductor substrate 11 is connected to ground. Based on the electrical field formed between the source and drainregions second control gate 19, electrons accumulated in the floatinggate 18 are injected into the source and drainregions tunnel insulation layer 14 b via the FN tunneling effect. As a result, the number of electrons from the floatinggate 18 is reduced, the threshold voltage of the flash memory device is decreased, and the intensity of the electric field is decreased. - As described above, the flash memory device and fabrication method according to the present invention provide a flash memory which is capable of rapidly performing data erasure and programming operations at low voltage by forming a floating gate on both sidewalls of the control gate and on the low density impurity regions (source and drain), simplifying the fabrication process by using a self-aligning process, and controlling the size of the floating gate.
- The foregoing embodiments are merely exemplary and are not to be construed as limiting the present invention. The present teaching can be readily applied to other types of apparatuses. The description of the present invention is intended to be illustrative, and not to limit the scope of the claims. Many alternatives, modifications, and variations will be apparent to those skilled in the art.
Claims (24)
1. A memory device, comprising:
a substrate;
a first region and a second region in the substrate;
a first insulation layer formed on the substrate;
a first conductive layer formed on a portion of the first insulation layer;
first and second conductive sidewall spacers positioned adjacent to first and second sidewalls of the first conductive layer, respectively;
a second insulation layer formed on the first and second conductive sidewall spacers; and
a second conductive layer formed on the insulation layer, the second conductive layer conductively coupled to the first conductive layer.
2. The device of , wherein the first and second regions are source and drain regions, respectively, the source and drain regions each include a low density doping region and a high density doping region.
claim 1
3. The device of , wherein portions of the first insulation layer are formed over the first and second regions.
claim 1
4. The device of , wherein the portions of the first insulation layer formed over the first and second regions are thinner than the portion of the first insulation layer on which the first conductive layer is formed.
claim 3
5. The device of , wherein the second insulation layer comprises portions that extend between the sidewall spacers and the first conductive layer.
claim 1
6. The device of , wherein the second insulation layer comprises portions formed between the sidewall spacers and the third conductive layer.
claim 1
7. The device of , wherein portions of the second insulation layer project above an upper surface of the first conductive layer pattern.
claim 1
8. The device of , wherein the first and third conductive layers form control gates.
claim 1
9. The device of , wherein the first and second conductive sidewall spacers form a floating gate.
claim 1
10. The device of , wherein the first and third conductive layers and the first and second conductive layer sidewall spacers are polysilicon.
claim 1
11. A method of making a memory device, comprising the steps of:
forming a first insulation layer on a substrate;
forming a first conductive layer pattern on a portion of the first insulation layer;
forming impurity regions in the substrate;
forming a second insulation layer on sidewalls of the first conductive layer pattern;
forming, on each of two sides of the first conductive layer pattern, a conductive sidewall spacer on the second insulation layer and the first insulation layer;
forming a third insulation layer that covers the conductive sidewall spacers; and
forming a third conductive layer pattern on the first, second and third insulation layers, the third conductive layer pattern conductively coupled to the first conductive layer pattern.
12. The method of , wherein the third insulation layer is formed so that it contacts the first and second insulation layers.
claim 11
13. The method of , wherein the step of forming impurity regions in the substrate comprises the steps of:
claim 11
forming low density impurity regions in the substrate; and
forming high density impurity regions in the substrate.
14. The method of , wherein the step of forming low density impurity regions comprises:
claim 13
forming a nitride film pattern on the first conductive layer pattern;
ion-implanting impurities in the substrate while using the nitride film patterns as a mask; and
removing the nitride film pattern.
15. The method of , wherein the step of forming high density impurity regions comprises:
claim 13
forming a nitride film pattern on the first conductive layer pattern;
ion-implanting impurities in the substrate while using the nitride film pattern and the conductive sidewall spacers as a mask; and
removing the nitride film pattern.
16. The method of , wherein the first and third conductive layer patterns form control gates.
claim 11
17. The method of , wherein the conductive sidewall spacers form a floating gate.
claim 11
18. The method of , wherein the first and third conductive layer patterns and the conductive sidewall spacers are polysilicon.
claim 11
19. The method of , wherein the second insulation layer is formed between the conductive sidewall spacers and the first conductive layer pattern.
claim 11
20. The method of , wherein the third insulation layer is formed between the conductive layer sidewall spacers and the third conductive layer pattern.
claim 11
21. The method of , wherein portions of the second insulation layer and the third insulation layer, which cover the conductive sidewall spacers, project above an upper surface of the first conductive layer pattern.
claim 11
22. The method of , wherein a first low density impurity region and a first high density impurity region together form a source region, and wherein a second low density impurity region and a second high density impurity region together form a drain region.
claim 13
23. The method of , wherein portions of the first insulation layer are formed over the source and drain regions.
claim 22
24. The method of , wherein the portions of the first insulation layer formed over the source and drain regions are thinner than the portion of the first insulation layer on which the first conductive layer is formed.
claim 23
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KR1019970008652A KR100206985B1 (en) | 1997-03-14 | 1997-03-14 | Flash memory device and fabrication method of the same |
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US09/020,503 US6187636B1 (en) | 1997-03-14 | 1998-02-09 | Flash memory device and fabrication method thereof |
US09/798,961 US20010009289A1 (en) | 1997-03-14 | 2001-03-06 | Flash memory device and fabrication method thereof |
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US20050285178A1 (en) * | 2004-06-28 | 2005-12-29 | Micron Technology, Inc. | Formation of memory cells and select gates of NAND memory arrays |
Families Citing this family (28)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JP3196717B2 (en) * | 1998-03-16 | 2001-08-06 | 日本電気株式会社 | Nonvolatile semiconductor memory device and method of manufacturing the same |
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JP5114824B2 (en) * | 2004-10-15 | 2013-01-09 | 富士通セミコンダクター株式会社 | Semiconductor device and manufacturing method thereof |
JP2008153374A (en) * | 2006-12-15 | 2008-07-03 | Oki Electric Ind Co Ltd | Nonvolatile semiconductor memory |
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US8791522B2 (en) * | 2011-10-12 | 2014-07-29 | Macronix International Co., Ltd. | Non-volatile memory |
US9263293B2 (en) * | 2014-01-10 | 2016-02-16 | Taiwan Semiconductor Manufacturing Co., Ltd. | Flash memory structure and method for forming the same |
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Family Cites Families (9)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
JPH0666329B2 (en) * | 1988-06-30 | 1994-08-24 | 株式会社東芝 | Method for manufacturing semiconductor device |
US5478767A (en) * | 1994-09-30 | 1995-12-26 | United Microelectronics Corporation | Method of making a flash EEPROM memory cell comprising polysilicon and textured oxide sidewall spacers |
JP3072754B2 (en) * | 1994-10-18 | 2000-08-07 | シャープ株式会社 | Method for manufacturing semiconductor device |
US5654212A (en) * | 1995-06-30 | 1997-08-05 | Winbond Electronics Corp. | Method for making a variable length LDD spacer structure |
US5716866A (en) * | 1995-08-30 | 1998-02-10 | Motorola, Inc. | Method of forming a semiconductor device |
KR0168355B1 (en) * | 1995-11-02 | 1999-02-01 | 김광호 | Interconnection forming method of semiconductor device |
US5599726A (en) * | 1995-12-04 | 1997-02-04 | Chartered Semiconductor Manufacturing Pte Ltd | Method of making a conductive spacer lightly doped drain (LDD) for hot carrier effect (HCE) control |
US5824584A (en) * | 1997-06-16 | 1998-10-20 | Motorola, Inc. | Method of making and accessing split gate memory device |
TW387151B (en) * | 1998-02-07 | 2000-04-11 | United Microelectronics Corp | Field effect transistor structure of integrated circuit and the manufacturing method thereof |
-
1997
- 1997-03-14 KR KR1019970008652A patent/KR100206985B1/en not_active IP Right Cessation
-
1998
- 1998-02-09 US US09/020,503 patent/US6187636B1/en not_active Expired - Lifetime
- 1998-03-06 JP JP10055117A patent/JP2961530B2/en not_active Expired - Fee Related
-
2001
- 2001-03-06 US US09/798,961 patent/US20010009289A1/en not_active Abandoned
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
US20050285178A1 (en) * | 2004-06-28 | 2005-12-29 | Micron Technology, Inc. | Formation of memory cells and select gates of NAND memory arrays |
US20060006456A1 (en) * | 2004-06-28 | 2006-01-12 | Micron Technology, Inc. | Memory cells and select gates of NAND memory arrays |
US7348236B2 (en) | 2004-06-28 | 2008-03-25 | Micron Technology, Inc. | Formation of memory cells and select gates of NAND memory arrays |
US7402861B2 (en) | 2004-06-28 | 2008-07-22 | Micron Technology, Inc. | Memory cells and select gates of NAND memory arrays |
Also Published As
Publication number | Publication date |
---|---|
KR19980073410A (en) | 1998-11-05 |
KR100206985B1 (en) | 1999-07-01 |
US6187636B1 (en) | 2001-02-13 |
JP2961530B2 (en) | 1999-10-12 |
JPH10261727A (en) | 1998-09-29 |
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