Dishwasher

A control method for a dishwasher that includes a spray arm, a sump configured to provide a space where washing water is stored and to collect washing water sprayed from the spray arm, a housing configured to connect the sump and the spray arm, a heater located in the housing, an impeller located in the housing and above the heater, and a motor configured to rotate the impeller, is described. The control method includes the actions of supplying washing water to the sump; rotating the impeller by supplying electricity to the motor; measuring an amount of electric current supplied to the motor during the rotating of the impeller; and heating washing water located in the housing by operating the heater based on the amount of electric current supplied to the motor during the rotating of the impeller being greater than or equal to a preset reference amount.

Dishwasher and control method thereof

A control method of a dishwasher that includes at least two flow paths having different flow rates, a chamber having communication holes that each communicate with a respective flow path, a water supply pump configured to supply washing water to the chamber through an impeller rotated by a motor, and a flow path switching unit located within the chamber and configured to sequentially open the communication holes is described. The control method includes the actions of measuring an amount of current supplied to the motor while the motor rotates the impeller to supply washing water to the chamber, and determining a position of the flow path switching unit by comparing the amount of current supplied to the motor with reference current amounts that are each designated as an amount of current supplied to the motor when the motor rotates the impeller to supply washing water to the respective flow path.

Dish washer

The present invention relates to a dishwasher. The dishwasher, according to one embodiment of the present invention, comprises: a wash tank that forms a space for washing dishes; a water supply device having a water chamber for collecting externally supplied water for washing dishes; a sump for receiving water from the water chamber and supplying washing water to the wash tank; and a heat exchange flow channel for exchanging heat with the washing water from the water chamber as the washing water flows from the sump through said channel.

Dishwasher and control method thereof

The present invention relates to a dishwasher and a control method thereof. According to one aspect, the dishwasher which washes dishes according to washing, rinsing, and drying steps comprises: a tub which is provided with a rack for accommodating dishes, and a washing nozzle for spraying washing water; a sump in which the washing water supplied to the tub is collected; a filter device which is provided to the sump, and allowing foreign substances of the washing water to be filtered; and a cleaning unit which clears away the foreign substances accumulated in the filter device.

DISHWASHER AND CONTROL METHOD THEREOF

The present invention relates to a dishwasher and a control method thereof. According to one aspect, the dishwasher which washes dishes according to washing, rinsing, and drying steps comprises: a tub which is provided with a rack for accommodating dishes, and a washing nozzle for spraying washing water; a sump in which the washing water supplied to the tub is collected; a filter device which is provided to the sump, and allowing foreign substances of the washing water to be filtered; and a cleaning unit which clears away the foreign substances accumulated in the filter device. 1. A dishwasher washing dishes according to washing , rinsing , and drying steps , comprising:a tub which is provided with a rack for accommodating dishes, and a washing nozzle for spraying washing water;a sump in which the washing water supplied to the tub is collected;a filter device provided to the sump, and allowing foreign substances of the washing water to be filtered; anda cleaning unit which clears away the foreign substances accumulated in the filter device.2. The dishwasher according to claim 1 , wherein the cleaning unit continuously or intermittently cleans the filter device during the washing step.3. The dishwasher according to claim 1 , wherein the cleaning unit cleans the filter device at the time when a water discharge pump operates during the rinsing step.4. The dishwasher according to claim 1 , wherein the cleaning unit includes an operating member operated for cleaning the filter device claim 1 , the operating member having a cleaning element contacting the filter device5. The dishwasher according to claim 4 , wherein the cleaning unit includes a motor to rotate the operating member.6. The dishwasher according to claim 4 , wherein the operating member includes a plurality of cleaning elements claim 4 ,the plurality of cleaning elements are spaced apart from one another.7. The dishwasher according to claim 1 , wherein the filter device includes a plurality of filters claim 1 ...

Dish washer

Provided is a dish washer. The dish washer includes a tub configured to accommodate dishes, a sump configured to supply water to the tub, and a water supply device configured to supply water received from an outer source to the sump or the tub. The water supply device includes a body and a plurality of discharge parts. The body includes a water supply passage along which water supplied from an outer source flows and a water chamber in which water supplied through the water supply passage is stored. Water is discharged from the water supply passage to the water chamber through the discharge parts.

DISHWASHER

A dishwasher includes a cabinet having a tub, a pump and at least one spray arm. The at least one spray arm has a flow path guide and first and second flow channels separated from each other. The flow path guide has a first opening to allow wash water to flow to the first flow channel and a second opening to allow wash water to flow to the second flow channel. A valve is coupled to the flow path guide and is configured to open or close one of the first opening and the second opening. The valve includes a rotatable float. The rotatable float closes the first opening while opening the second opening at a first point in time, and the rotatable float rotates to open the second opening while closing the second opening at a second point in time.

CONTROL METHOD OF DISHWASHER

A control method of a dishwasher including a pre-filter cleaning cycle of supplying steam generated in a sump to a filter assembly to self-clean the filter assembly, wherein the pre-filter cleaning cycle includes a pre-operation water supply step of driving a water supply module to supply wash water to the sump before operating the dishwasher, a pre-cleaning steam generation and supply step of driving a heater module to generate steam in the sump and supplying the generated steam to the filter assembly to clean the filter assembly after the pre-operation water supply step, and a pre-cleaning drainage step of driving a drainage module to drain the wash water after the pre-cleaning steam generation and supply step. In the control method of the dishwasher, steam is supplied to the filter assembly before or after a washing cycle of washing dishes in order to self-clean the filter assembly. 1. A control method of a dishwasher comprising a pre-filter cleaning cycle of supplying steam generated in a sump to a filter assembly to self-clean the filter assembly , wherein the pre-filter cleaning cycle comprises:a pre-operation water supply step of driving a water supply module to supply wash water to the sump before operating the dishwasher;a pre-cleaning steam generation and supply step of driving a heater module to generate steam in the sump and supplying the generated steam to the filter assembly to clean the filter assembly after the pre-operation water supply step; anda pre-cleaning drainage step of driving a drainage module to drain the wash water after the pre-cleaning steam generation and supply step.2. The control method according to claim 1 , further comprising a pre-operation drainage step of driving the drainage module to drain the wash water stored in the sump before the pre-filter cleaning cycle.3. The control method according to claim 1 , wherein the pre-filter cleaning cycle is performed periodically.4. The control method according to claim 1 , further ...

Dishwasher and Method of Controlling the Same

The present invention relates to a dishwasher that can save wash water for cleaning and a method of controlling the dishwasher. A method of controlling a dishwasher according to an exemplary embodiment of the present invention is a method of controlling a dishwasher having a circulation channel through which wash water is supplied to wash a plurality of arms by a wash pump after collecting the wash water, sprayed in to a tub from the plurality of wash arms, in a sump, and the method includes: performing a first water-supplying for supplying a predetermined amount of wash water into the dishwasher by opening a water supply valve; performing a first washing where the plurality of wash arms spray the wash water into the tub to be circulated by operating the wash pump; performing a first draining for saving recycling wash water as much as the volume of the circulation channel and draining the rest of the wash water to the outside of the dishwasher by operating the wash pump and the drain pump; and performing a second water-supplying for supplying the amount of wash water except the amount of the recycling wash water from a predetermined amount of wash water into the dishwasher by opening the water supply valve. 1. A method of controlling a dishwasher having a circulation channel through which wash water is supplied to a plurality of wash arms by a wash pump after collecting the wash water in a sump , the wash water having been previously sprayed into a tub from the plurality of wash arms , the method comprising:performing a first water-supplying for supplying a predetermined amount of wash water into the dishwasher by opening a water supply valve;performing a first washing, wherein the plurality of wash arms sequentially spray the wash water into the tub to be circulated by operating the wash pump;performing a first draining for saving recycling wash water and draining the rest of the wash water to the outside of the dishwasher by operating the wash pump and a drain ...

DISHWASHER AND METHOD OF CONTROLLING THE SAME

The present invention relates to a dishwasher that can save wash water for cleaning and a method of controlling the dishwasher. A method of controlling a dishwasher according to an exemplary embodiment of the present invention is a method of controlling a dishwasher having a circulation channel through which wash water is supplied to wash a plurality of arms by a wash pump after collecting the wash water, sprayed in to a tub from the plurality of wash arms, in a sump, and the method includes: performing a first water-supplying for supplying a predetermined amount of wash water into the dishwasher by opening a water supply valve; performing a first washing where the plurality of wash arms spray the wash water into the tub to be circulated by operating the wash pump; performing a first draining for saving recycling wash water as much as the volume of the circulation channel and draining the rest of the wash water to the outside of the dishwasher by operating the wash pump and the drain pump; and performing a second water-supplying for supplying the amount of wash water except the amount of the recycling wash water from a predetermined amount of wash water into the dishwasher by opening the water supply valve. 1. A method of controlling a dishwasher having a circulation channel through which wash water is supplied to a plurality of wash arms using a wash pump after collecting the wash water in a sump , the wash water having been previously sprayed in to a tub from the plurality of wash arms , the method comprising:performing a first water-supplying for supplying a predetermined amount of wash water into the dishwasher by opening a water supply valve;performing a first washing wherein the plurality of wash arms spray the wash water into the tub to be circulated by operating the wash pump;performing a first draining for saving recycling wash water and draining the rest of the wash water to the outside of the dishwasher by operating the wash pump and a drain pump; ...

DISHWASHER

The dishwasher of the present invention includes: a tub in which a dish washing space is formed; a sump which contains washing water supplied into the tub; a spray module which sprays washing water toward dishes; a pump which supplies the washing water stored in the sump to the spray module; an air jet generator which receives a part of the washing water discharged from the pump to form an air bubble in the washing water; and a discharge module which discharges the washing water containing the air bubble discharged from the air jet generator to a side surface of the tub. 1. A dishwasher comprising:a tub in which a dish washing space is formed;a sump which contains washing water supplied into the tub;a spray module which sprays washing water toward dishes;a pump which supplies the washing water stored in the sump to the spray module;an air jet generator which receives a part of the washing water discharged from the pump to form an air bubble in the washing water; anda discharge module which discharges the washing water containing the air bubble discharged from the air jet generator to a side surface of the tub.2. The dishwasher of claim 1 , wherein a side surface hole for discharging the washing water introduced into the discharge module into the tub is formed on a side surface of the tub.3. The dishwasher of claim 2 , wherein the side surface hole is formed at a height of being equal to or less than half a full height of the tub.4. The dishwasher of claim 1 , wherein the discharge module comprises:a main discharge pipe to which the washing water discharged from the air jet generator is introduced;a tub discharge pipe which is connected to the main discharge pipe and connected to the tub; anda sealer which seals a space between the main discharge pipe and the tub discharge pipe.5. The dishwasher of claim 4 , wherein the main discharge pipe comprises:a first main discharge pipe which is connected to the air jet generator; anda second main discharge pipe which connects ...

WIRE ASSEMBLY FOR ROTARY ELECTRIC MACHINE AND CORRESPONDING METHOD TO OBTAIN THE WIRE ASSEMBLY

The invention relates to a wire assembly for electric rotary machine comprising a plurality of phase coils (P-P), 14416. Wire assembly () for electric rotary machine comprising a plurality of phase coils (P-P) ,{'b': 1', '6', '18', '10, 'each phase coils (P-P) being aimed to be inserted in a dedicated set of slots () of a stator (),'}{'b': 1', '6', '61', '1', '6', '62', '1', '6', '61', '62, 'each phase coil (P-P) comprising a first part () having an input (I-I) and a second part () having an output (O-O), said first part () and second part () constituting a distributed wave winding,'}{'b': 1', '6', '63', '61', '62', '1', '6', '23, 'wherein each phase coil (P-P) comprises a U-turn part () linking the first () and the second () parts so that each phase coil (P-P) is composed of a single wire ().'}22316. Wire assembly according to claim 1 , wherein the wire () of each phase coil (P-P) comprises:{'b': 25', '18', '10, 'a plurality of straight portions () aimed to be inserted into the slots () of the stator (), and'}{'b': 26', '25, 'a plurality of end-loop portions () linking the straight portions (),'}{'b': 26', '25', '1', '2, 'said end-loop portions () linking a plurality of consecutive straight portions () being positioned in a same layer (L, L) of conductors.'}3616216252525. Wire assembly according to claim 1 , wherein claim 1 , in the first () and second () parts of each phase coil (P-P) claim 1 , a given straight portion () is linked to two adjacent straight portions () disposed on two opposite sides of the given straight portion ().463252526. Wire assembly according to claim 1 , wherein claim 1 , in the U-turn part () claim 1 , a straight portion () is linked to two straight portions () positioned on the same side through end-loop portions ().5632564. Wire assembly according to claim 1 , wherein claim 1 , in the U-turn part () claim 1 , the straight portion () comprises a slope portion ().66444. Wire assembly according to claim 5 , wherein the slope portion () is ...

DISHWASHER AND CONTROL METHOD THEREOF

A control method of a dishwasher that includes at least two flow paths having different flow rates, a chamber having communication holes that each communicate with a respective flow path, a water supply pump configured to supply washing water to the chamber through an impeller rotated by a motor, and a flow path switching unit located within the chamber and configured to sequentially open the communication holes is described. The control method includes the actions of measuring an amount of current supplied to the motor while the motor rotates the impeller to supply washing water to the chamber, and determining a position of the flow path switching unit by comparing the amount of current supplied to the motor with reference current amounts that are each designated as an amount of current supplied to the motor when the motor rotates the impeller to supply washing water to the respective flow path. 1. A control method of a dishwasher configured to spray washing water to objects to be washed that the dishwasher including at least two flow paths having different flow rates , a chamber having communication holes that each communicate with a respective flow path , a water supply pump configured to supply washing water to the chamber through an impeller rotated by a motor , and a flow path switching unit located within the chamber and configured to sequentially open the communication holes based on washing water being supplied to the chamber , the control method comprising:measuring an amount of current supplied to the motor while the motor rotates the impeller to supply washing water to the chamber; anddetermining a position of the flow path switching unit by comparing the amount of current supplied to the motor with reference current amounts that are each designated as an amount of current supplied to the motor when the motor rotates the impeller to supply washing water to the respective flow path.2. The control method according to claim 1 , further comprising notifying ...

DISHWASHER

A control method for a dishwasher that includes a spray arm, a sump configured to provide a space where washing water is stored and to collect washing water sprayed from the spray arm, a housing configured to connect the sump and the spray arm, a heater located in the housing, an impeller located in the housing and above the heater, and a motor configured to rotate the impeller, is described. The control method includes the actions of supplying washing water to the sump; rotating the impeller by supplying electricity to the motor; measuring an amount of electric current supplied to the motor during the rotating of the impeller; and heating washing water located in the housing by operating the heater based on the amount of electric current supplied to the motor during the rotating of the impeller being greater than or equal to a preset reference amount. 1. A control method for a dishwasher comprising a spray arm configured to spray washing water to a washing object , a sump configured to provide a space where washing water is stored and to collect washing water sprayed from the spray arm , a housing configured to connect the sump and the spray arm , a heater located in the housing , an impeller located in the housing and above the heater , and a motor configured to rotate the impeller , the control method comprising:supplying washing water to the sump;rotating the impeller by supplying electricity to the motor;measuring an amount of electric current supplied to the motor during the rotating of the impeller; andheating washing water located in the housing by operating the heater based on the amount of electric current supplied to the motor during the rotating of the impeller being greater than or equal to a preset reference amount.2. The control method for the dishwasher of claim 1 , wherein the impeller rotates at a preset revolutions per minute (RPM) that is higher than an RPM of the impeller to spray washing water from the spray arm and lower than an RPM of the ...

DISHWASHER AND METHOD FOR CONTROLLING SUCH DISHWASHER

DISHWASHER AND METHOD FOR CONTROLLING SUCH DISHWASHER

La présente invention concerne un lave-vaisselle (1) qui peut économiser l'eau de lavage pour le nettoyage et un procédé de commande du lave-vaisselle (1) qui selon un exemple de mode de réalisation de la présente invention est un procédé de commande d'un lave-vaisselle (1) comportant un canal de circulation à travers lequel l'eau de lavage est fournie pour laver une pluralité de bras (13, 14, 15) par une pompe de lavage (150) après recueil de l'eau de lavage, pulvérisée dans une cuve (12) par la pluralité de bras de lavage (13, 14, 15), dans un collecteur, et le procédé comprend: la réalisation d'une première alimentation en eau (S310) ; la réalisation d'un premier lavage (S320) ; la réalisation d'une première vidange (S330) ; et la réalisation d'une deuxième alimentation en eau (S340). The present invention relates to a dishwasher (1) which can save washing water for cleaning and a method of controlling the dishwasher (1) which according to an exemplary embodiment of the present invention is a method of controlling a dishwasher (1) having a circulation channel through which the wash water is supplied to wash a plurality of arms (13, 14, 15) by a washing pump (150) after collection of the washing water, sprayed into a tank (12) by the plurality of wash arms (13,14,15) in a manifold, and the method comprises: providing a first water supply (S310); performing a first wash (S320); the realization of a first emptying (S330); and making a second water supply (S340).

dishwasher

Dish washer

Control method of dishwasher

Dish washer

The dish washer according to one embodiment of the present invention comprises: a tub having a dish washing space formed therein; a sump containing wash water to be supplied into the tub; a spray module for spraying the wash water toward dishes; a pump for supplying the wash water stored in the sump to the spray module; an air jet generator for receiving a part of the wash water discharged from the pump and generating air bubbles in the wash water; and a discharge module for discharging, to the side of the tub, the wash water discharged from the air jet generator.

Hardmask composition, hardmask layer, and method of forming patterns

Provided are a hardmask composition including a polymer including a structural unit represented by Chemical Formula 1 and a structural unit represented by Chemical Formula 2, and a solvent, a hardmask layer manufactured from the hardmask composition, and a method of forming patterns from the hardmask composition, wherein the definitions of Chemical Formula 1 and Chemical Formula 2 are as described in the specification.

Dish washer

The dish washer according to one embodiment of the present invention comprises: a tub having a dish washing space formed therein; a sump containing wash water to be supplied into the tub; a spray module for spraying the wash water toward dishes; a pump for supplying the wash water stored in the sump to the spray module; an air jet generator for receiving a part of the wash water discharged from the pump and generating air bubbles in the wash water; and a discharge module for discharging, to the side of the tub, the wash water discharged from the air jet generator.

Waterproof structure and electronic device comprising same

An electronic device is provided. The electronic device includes a body having a passage, a physical button having a rod passing through the passage, an inner surface having a first convex surface and a second convex surface formed to be spaced apart from the first convex surface, a through-hole formed by the inner surface, an outer surface having a third convex surface and a protruding surface formed to be spaced apart from the third convex surface, a bottom surface formed between the inner surface and the outer surface, and a waterproof member having a fourth convex surface formed in the direction facing the bottom surface, wherein the waterproof member is arranged between the body and the rod.

A control method of a dish washer

Semiconductor device having doped interlayer insulating layer

A semiconductor device includes a lower memory stack disposed on a substrate and including lower gate electrodes and a lower staircase structure, an upper memory stack including upper gate electrodes and an upper staircase structure, a lower interlayer insulating layer doped with an impurity and covering the lower staircase structure, the lower interlayer insulating layer having a doping concentration gradually increasing toward the lower staircase structure, an upper interlayer insulating layer doped with an impurity and covering the upper staircase structure and the lower interlayer insulating layer, the upper interlayer insulating layer having a doping concentration gradually increasing toward the upper staircase structure and the lower interlayer insulating layer, lower contact plugs and upper contact plugs contacting the lower gate electrodes and the upper gate electrodes, respectively.

Waterproof structure and electronic device comprising same

An electronic device according to various embodiments of the present disclosure comprises: a body having a passage; a physical button having a rod passing through the passage; an inner surface having a first convex surface and a second convex surface formed to be spaced apart from the first convex surface; a through-hole formed by the inner surface; an outer surface having a third convex surface and a protruding surface formed to be spaced apart from the third convex surface; a bottom surface formed between the inner surface and the outer surface; and a waterproof member having a fourth convex surface formed in the direction facing the bottom surface, wherein the waterproof member is arranged between the body and the rod, the rod is inserted to pass through the through-hole, and the waterproof member can be arranged such that the first convex surface and the second convex surface comes into close contact with the rod, and the third convex surface and the protruding surface come into close contact with one surface of the body. Other various embodiments identified through the specification are possible.

Attache pour relier un blindage interne au cadre d'un tube a rayons cathodiques.

Three-dimensional semiconductor memory device and electronic system including the same

Disclosed are a three-dimensional semiconductor memory device, a method of fabricating the same, and an electronic system including the same. The semiconductor memory device may include a substrate including a first region and a second region, a plurality of stacks including first and second stacks, each of which includes interlayer insulating layers and gate electrodes stacked alternately with the interlayer insulating layers on the substrate and has a stepped structure on the second region, an insulating layer on stepped structure of the first stack, a plurality of vertical channel structures provided on the first region to penetrate the first stack, and a separation structure separating the first and second stacks from each other. The insulating layer may include one or more dopants, and a dopant concentration of the insulating layer may decrease as a distance from the substrate increases.

Waterproof structure and electronic device comprising same

Attache pour relier un blindage interne au cadre d'un tube a rayons cathodiques.

Attache pour relier un blindage intérieur à un cadre d'un tube à rayons cathodiques comprenant: une première partie courbée élastique (1) formant une extrémité pointue de l'attache et courbée selon un angle de 60 à 90degré ; des premières parties courbées (2) formées en courbant vers l'intérieur les prolongements de la première partie courbée élastiques, des secondes parties courbées (3) formées en courbant vers l'extérieur les prolongements des premières parties courbées, des secondes parties courbées élastiques (4) formées en courbant en forme de U les prolongements des secondes parties courbées, et des parties de préhension (5) prévues sous la forme de prolongements vers le bas des secondes parties courbées élastiques. L'attache de la présente invention possède une forme commode pour des travaux manuels et n'est pas soumise aux exigences de sens qui sont rencontrées avec des trous de fixation rectangulaires.

Dishwasher and control method for the same

Electronic device and method for providing list of suggested utterances

An example electronic device may include a memory configured to store instructions and a processor electrically connected to the memory and configured to execute the instructions. When the instructions are executed by the processor, the processor may be configured to generate a first suggested-utterance list providable to a user and generate a second suggested-utterance list by extracting, from the first suggested-utterance list, utterances capable of successful execution for a device registered to the user, according to state information about the registered device.

Dish washer

Provided is a dish washer. The dish washer includes a tub configured to accommodate dishes, a sump configured to supply water to the tub, and a water supply device configured to supply water received from an outer source to the sump or the tub. The water supply device includes a body and a plurality of discharge parts. The body includes a water supply passage along which water supplied from an outer source flows and a water chamber in which water supplied through the water supply passage is stored. Water is discharged from the water supply passage to the water chamber through the discharge parts.

Dish washer

Provided is a dish washer. The dish washer includes a tub configured to accommodate dishes, a sump configured to supply water to the tub, and a water supply device configured to supply water received from an outer source to the sump or the tub. The water supply device includes a body and a plurality of discharge parts. The body includes a water supply passage along which water supplied from an outer source flows and a water chamber in which water supplied through the water supply passage is stored. Water is discharged from the water supply passage to the water chamber through the discharge parts.

Lavavajillas

Un lavavajillas que comprende: un contenedor (104) configurado para acomodar platos; un sumidero (105) configurado para suministrar agua al contenedor; y un dispositivo de suministro de agua (200) configurado para suministrar el agua recibida desde una fuente externa al sumidero (105) o el contenedor (104), en donde el dispositivo de suministro de agua (200) comprende: un cuerpo (201) que comprende un paso de suministro de agua (205) a lo largo del cual fluye el agua suministrada desde la fuente externa y una cámara de agua (206) en la que se almacena el agua suministrada a través del paso de suministro de agua (205); y una pluralidad de partes de descarga (210) a través de las cuales el agua se descarga desde el paso de suministro de agua (205) a la cámara de agua (206), caracterizado por que el cuerpo (201) tiene una primera superficie (202) que enfrenta al contenedor (104) y una segunda superficie (203) opuesta a la primera superficie (202), y el agua en el paso de suministro de agua (205) se descarga a través de las partes de descarga (210) en una dirección hacia la primera superficie (202).

Klem voor het koppelen van een binnenscherm met een frame van een kathodestraalbuis.

Klem voor het koppelen van een binnenscherm met een frame van een kathodestraalbuis.

Electronic device and recommended utterance list providing method

An example electronic device may include a memory configured to store instructions and a processor electrically connected to the memory and configured to execute the instructions. When the instructions are executed by the processor, the processor may be configured to generate a first suggested-utterance list providable to a user and generate a second suggested-utterance list by extracting, from the first suggested-utterance list, utterances capable of successful execution for a device registered to the user, according to state information about the registered device.

[UNK]

Semiconductor device having doped interlayer insulating layer

A semiconductor device includes a lower memory stack disposed on a substrate and including lower gate electrodes and a lower staircase structure, an upper memory stack including upper gate electrodes and an upper staircase structure, a lower interlayer insulating layer doped with an impurity and covering the lower staircase structure, the lower interlayer insulating layer having a doping concentration gradually increasing toward the lower staircase structure, an upper interlayer insulating layer doped with an impurity and covering the upper staircase structure and the lower interlayer insulating layer, the upper interlayer insulating layer having a doping concentration gradually increasing toward the upper staircase structure and the lower interlayer insulating layer, lower contact plugs and upper contact plugs contacting the lower gate electrodes and the upper gate electrodes, respectively.