KR20100068794A - Nonvolatile programmable switch device and fabricating method thereof - Google Patents

Abstract

PURPOSE: A nonvolatile programmable switch device and a method for manufacturing the same are provided to reduce an area in which the device is occupied by maintaining the property of the programmable switch device without a static random access memory device. CONSTITUTION: A first electrode(102) is formed on a semiconductor substrate(100). An insulating layer(104) comprises a contact hole(106) which exposes a part of the first electrode. A heat-generating electrode(108) is buried in the contact hole. A phase-changing layer(118) is formed on the heat-generating electrode. A metal layer(112) is contacted with both sides of the phase-changing layer. A second electrode(130) is connected to the phase-changing layer.

Description

Nonvolatile programmable switch device and method for manufacturing same

The present invention relates to a nonvolatile programmable switch device and a method of manufacturing the same, and more particularly, to a nonvolatile programmable switch device using a phase change material and a method of manufacturing the same.

Semiconductor devices are largely classified into memory devices capable of storing information only and non-memory devices capable of functions other than information storage. According to Gartner Dataquest, the world's most prestigious semiconductor market research institute, the global semiconductor device market as of 2005 Specific gravity has a ratio of 22% for memory devices and 78% for non-memory devices.

Non-memory semiconductor devices are largely classified into the following two representative market groups. One of them is a micro-component, which is a central processing unit (CPU), a micro controller unit (MCU), a micro peripheral (MPR) and a digital signal processor (DSP). process). The other is an application specific integrated circuit (ASIC) / application specific standard product (ASSP), known as an on-demand semiconductor device, which is half of the total memory semiconductor market in terms of one ASIC, and the entire memory semiconductor market integrating ASIC / ASSP. It occupies a large market that is 1.5 times the size.

Field programmable gate arrays (FPGAs), grouped in a family of ASICs, are representatives of reconfigurable large scale integration (LSI), each time a semiconductor chip meets customers' diverse functions and needs. Instead of making a whole new one, it has the advantage that various functions can be implemented by reconfiguring some functions of the circuit to meet the needs of users. FPGAs have programmable switch devices for reconfiguring some of the circuit functions. Conventional programmable switch devices typically consist of one transistor and one static random access memory (SRAM) device. However, in the case of the existing programmable switch device, due to the inherent characteristics of the SRAM itself, disadvantages of volatility and large cross-sectional area have disadvantages of high manufacturing cost.

Many studies have been conducted to remedy this disadvantage, and solid electrolyte devices have been studied as an alternative. However, the solid electrolyte device has a problem of CMOS compatibility and has not completely solved the problem of CMOS application at the chip level. In addition, the solid electrolyte memory device exposes reliability problems such as a sudden change in the ON / OFF threshold voltage value and read retention according to the measurement temperature. In order to use solid electrolyte devices in programmable switch devices, requirements such as CMOS application and reliability must be met.

The problem to be solved by the present invention is to provide a nonvolatile programmable switch device using a phase change material (or phase change layer) in order to solve the above problems.

In addition, another object of the present invention is to provide a method of manufacturing a nonvolatile programmable switch device using a phase change material (or phase change layer).

In order to solve the above problem, the nonvolatile programmable switch device of the present invention includes an insulating layer having a first electrode formed on a semiconductor substrate and a contact hole exposing a portion of the first electrode on the first electrode. The heating electrode is embedded in the contact hole. The phase change layer is formed on the heating electrode. Metal layers in contact with both sides of the phase change layer are formed. A second electrode connected to the phase change layer and insulated from the metal layer is formed. The third electrode is formed by being connected to one side of the metal layer around the phase change layer. The fourth electrode is formed by being connected to the other side of the metal layer around the phase change layer.

The metal layer may be formed in contact with a portion of the side surface of the phase change layer, or the metal layer may be formed in contact with all of the side surfaces of the phase change layer. The first electrode and the second electrode may be write-only electrodes, and the third and fourth electrodes may be read-only electrodes that detect resistance values of the phase change layer through the metal layer.

And a second insulating layer and a third insulating layer having a first via hole and a third via hole exposing one side portion and the other side portion of the metal layer around the phase change layer, and a second via hole having a second via hole on the phase change layer. The third electrode and the fourth electrode may be embedded in the first via hole and the third via hole, respectively, and the second electrode may be formed in the second via hole. The first electrode and the second electrode may be electrically separated from the third electrode and the fourth electrode.

In order to solve the other problem described above, the manufacturing method of the nonvolatile programmable switch device of the present invention is to form a first electrode on a semiconductor substrate, and to form a first insulating layer having a contact hole exposing the first electrode. Include. A heating electrode embedded in the contact hole is formed. A phase change layer is formed on the heating electrode. Metal layers and second insulating layers are sequentially formed on both sides of the phase change layer.

A third insulating layer is formed on the second insulating layer and the metal layer to cover the phase change layer. The third and second insulating layers are patterned to form third and fourth electrodes on one side and the other side of the metal layer around the phase change layer, and a second electrode is formed on the phase change layer.

Forming a metal layer having a pore exposing the heating electrode and the second insulating layer on the heating electrode and the first insulating layer, forming a phase change material layer in contact with the heating electrode and the metal layer while filling the pore, and forming a second insulating layer The phase change layer may be formed by planarizing the phase change material layer with an etch stop layer.

A phase change layer is formed on the heating electrode and the first insulating layer, a metal material layer and an insulating material layer are formed on the first insulating layer to cover the phase change layer, and the phase change layer is an etch stop layer. And the phase change layer, the metal layer, and the second insulating layer may be formed by planarizing the metal material layer.

Patterning a third insulating layer and the second insulating layer to form a first via hole and a third via hole on the metal layer on both sides of the phase change layer, a second via hole is formed on the phase change layer, the first via hole, the first The method may include forming a third electrode, a second electrode, and a fourth electrode embedded in the second via hole and the third via hole, respectively.

The third electrode and the fourth electrode may be read-only electrodes in the programmable switch element operation, and the first electrode and the second electrode may be write-only electrodes in the programmable switch element operation.

The nonvolatile programmable switch device of the present invention has four terminals and has a structure in which the first electrode 102 and the second electrode 130, and the third electrode 128 and the fourth electrode 132 are completely separated. . That is, in the programmable switch device of the present invention, since the read-only electrodes (read-only terminals) and the write-only electrodes (write-only terminals) are completely separated from each other, device retention characteristics even under a current or voltage applied thereto. Can improve.

Since the nonvolatile programmable switch device of the present invention does not include an SRAM device, the area occupied by the device may be reduced as described above, and the nonvolatile programmable switch device may have a nonvolatile property since the phase change layer 118 is included.

The present inventors have determined that the use of a resistance change type phase change material (or phase change layer) in a programmable switch element can solve conventional problems for the following reasons.

Phase change materials are proven materials that are already widely used in the optical industry such as DVD. Phase change materials are stable materials because they are widely used in phase change memory devices in the semiconductor field. The phase change material represented by Ge ₂ Sb ₂ Te ₅ (GST) changes to a low resistance crystal or high resistance amorphous state depending on the applied current or voltage conditions, even when the power is turned off. Retained nonvolatile memory characteristics.

The phase change material can be switched (on, low resistance) or off (amorphous, high resistance) depending on the crystalline or amorphous state. Thus, the phase change material can be made to retain all the characteristics of one transistor and one SRAM element, which are conventional programmable switch elements. In addition, the phase change material can implement a programmable switch element having a non-volatile and small cross-sectional area that conventional programmable switch elements do not have. Since phase change materials are widely used in phase change memory devices, a CMOS matching process is possible, and they may also have characteristics of being resistant to radiation.

The nonvolatile programmable switch device of the present invention requires device retention characteristics in a bias application situation. Therefore, the nonvolatile programmable switch device of the present invention is designed to improve the device retention characteristics by completely separating the read electrode (terminal) and the write terminal.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings. However, the embodiments of the present invention illustrated in the following may be modified in many different forms, and the scope of the present invention is not limited to the embodiments described below, but may be implemented in various different forms. Embodiments of the present invention are provided to more completely explain the present invention to those skilled in the art. In the following figures, like reference numerals refer to like elements.

1 is a cross-sectional view of a nonvolatile programmable switch device according to a first embodiment of the present invention.

Specifically, the nonvolatile programmable switch device according to the present invention shown in FIG. 1 illustrates only one unit device portion formed on the semiconductor substrate 100 as a four-electrode (terminal) device for convenience. In the nonvolatile programmable switch device, a first electrode 102 is formed on a semiconductor substrate 100. The first electrode 102 is composed of a metal film. The first electrode 102 is used as a write-only electrode in the operation of the programmable switch element. A first insulating layer 104 having a contact hole 106 exposing a part of the first electrode 102 while covering the first electrode 102 is formed. The heating electrode 108 is buried in the contact hole 106.

The metal layer 112 having the pores 110 exposing the heating electrode 108 is formed on the heating electrode 108 and the first insulating layer 104. The pore 110 is provided with a phase change layer 118 in contact with the heating electrode 108 and the metal layer 112. The metal layer 112 is formed to surround a portion of the side surface of the phase change layer 118. On the metal layer 112, a second insulating layer 114a exposing a part of the metal layer 112 is formed around the phase change layer 118.

The third insulating layer 120 having the first via hole 122, the second via hole 124, and the third via hole 126 exposing the metal layer 112 and the phase change layer 118 on the second insulating layer 114a. ) Is formed. A second electrode 130 connected to the phase change layer 118 and insulated from the metal layer 112 is formed in the second via hole 124. The second electrode 130 is used as a write-only electrode during the operation of the programmable switch device.

A third electrode 128 connected to one side of the metal layer 112 is formed in the first via hole 122. The fourth electrode 132 connected to the other side of the metal layer 112 is formed in the third via hole 126. The third electrode 128 and the fourth electrode 132 are used as read-only electrodes for detecting the resistance value of the phase change layer 118 through the metal layer 112 during the operation of the programmable switch element. The phase change layer 118 is made of a chalcogenide alloy that can be Joule heated by a current or voltage applied through the first electrode 102 and the second electrode 130.

As a result, in the nonvolatile programmable switch device according to the present invention illustrated in FIG. 1, a heating electrode 108 is formed and connected to the first electrode 102. The phase change layer 118 and the second electrode 130 are sequentially formed and connected to the heating electrode 108. The metal layer 112 is connected to the left and right sides of the phase change layer 118 and is connected to the phase change layer 118.

One side of the metal layer 112 positioned on the left side of the phase change layer 118 is connected to the third electrode 128, and the other side of the metal layer 112 positioned on the right side of the phase change layer 118 is the fourth electrode. 132 is connected. As described above, the first electrode 102 and the second electrode 130 are used as write-only electrodes in the programmable switch device operation, and the third electrode 128 and the fourth electrode 132 are operated in the programmable switch device operation. Used as a read-only electrode.

The nonvolatile programmable switch device of the present invention as described above has four terminals, and the first electrode 102 and the second electrode 130, and the third electrode 128 and the fourth electrode 132 are completely separated. Structure. That is, the programmable switch device of the present invention is completely separated from the read-only electrodes (read-only terminals 128 and 132) and the write-only electrodes (write-only terminals 102 and 130) even when a current or voltage is applied. Device retention characteristics can be improved.

Since the nonvolatile programmable switch device of the present invention does not include the SRAM device, the area occupied by the device can be reduced as described above, and the nonvolatile programmable switch device has a nonvolatile property because the phase change layer 118 is included. Since the nonvolatile programmable switch device of the present invention is nonvolatile, a separate external memory is not required, thereby lowering manufacturing costs and reducing the risk of information leakage. In addition, the nonvolatile programmable switch device of the present invention does not include an SRAM device, so that the cross-sectional area occupied by the device can be reduced, thereby reducing the on resistance.

Next, the operation of the nonvolatile programmable switch device of FIG. 1 will be described in more detail.

First, the write operation will be described. A current or voltage is applied to the first electrode 102 or the second electrode 130, and the heating electrode 108 is Joule heated by the applied current or voltage, thereby heating the phase change layer 118. . When the heated phase change layer 118 is rapidly cooled after the temperature rises above the melting point, it is written off as an amorphous state of high resistance, and is lowered when the phase change layer 118 is cooled slowly after rising to a temperature above the crystallization temperature and below the melting point temperature. It is written in the on state as the determination state of the resistance. The phase change layer 118 has a nonvolatile characteristic that its resistance state is maintained even when the power is turned off.

Next, the read operation will be described. For the read operation, the metal layer 112 positioned on the left and right sides of the phase change layer 118, and the third electrode 128 and the fourth electrode 132 connected thereto are used. When the resistance value of the phase change layer 118 is high, it is read off, and when the resistance value of the phase change layer 118 is low, it is read on. In particular, in the nonvolatile programmable switch device of FIG. 1, since the metal layer 112 is formed to contact some side surface of the phase change layer 118, the resistance change may be effectively detected during the read operation of the phase change layer 118. Can be.

2 is a cross-sectional view of a nonvolatile programmable switch device according to a second embodiment of the present invention.

Specifically, in the nonvolatile programmable switch device according to the second embodiment of the present invention, the metal layer 212a contacts all of the side surfaces of the phase change layer 210 and the second electrode 226 as compared with the first embodiment. It is the same in operation and structure except that it is formed only on a part of the surface of the phase change layer 210. As will be described later, the nonvolatile programmable switch element according to the second embodiment of the present invention is different from the manufacturing method of the first embodiment.

In more detail, the first electrode 102 is formed on the semiconductor substrate 100, the first insulating layer having a contact hole exposing a part of the first electrode 102 is formed, and the contact hole is formed. The heat generating electrode is formed in the inside. The first electrode 102 is used as a write-only electrode in the operation of the programmable switch element. The phase change layer 210 in contact with the heating electrode 108 is formed on the heating electrode 108. Metal layers 212a in contact with the phase change layer 210 are formed at both sides of the phase change layer 210. The metal layer 212a is formed to contact the entire side surface of the phase change layer 210. On the metal layer 212a, a second insulating layer 214b exposing a part of the metal layer 212a is formed around the phase change layer 210.

The third insulating layer 216a having the first via hole 218, the second via hole 220, and the third via hole 22 exposing the metal layer 212a and the phase change layer 210 on the second insulating layer 214b. ) Is formed. A second electrode 226 connected to the phase change layer 210 and insulated from the metal layer 212a is formed in the second via hole 220. The second electrode 226 is used as a write only electrode in the operation of the programmable switch element. A third electrode 224 connected to one side of the metal layer 212a is formed in the first via hole 218. The fourth electrode 228 connected to the other side of the metal layer 212a is formed in the third via hole 222. The third electrode 224 and the fourth electrode 228 are used as read-only electrodes in the operation of the programmable switch element.

As a result, in the nonvolatile programmable switch device according to the present invention illustrated in FIG. 2, a heating electrode 108 is formed and connected to the first electrode 102. The phase change layer 210 and the second electrode 226 are sequentially formed and connected to the heating electrode 108. The metal layers 212a are connected to the left and right sides of the phase change layer 210 to be connected to the phase change layer 210. One side of the metal layer 212a positioned on the left side of the phase change layer 210 is connected to the third electrode 224, and the other side of the metal layer 212a positioned on the right side of the phase change layer 210 is the fourth electrode. 228 is connected. As described above, the first electrode 102 and the second electrode 226 are used as write-only electrodes in the programmable switch element operation, and the third electrode 224 and the fourth electrode 228 are operated in the programmable switch element operation. Used as a read-only electrode. The phase change layer 210 is made of a chalcogenide alloy that can be Joule heated by a current or voltage applied through the first electrode 102 and the second electrode 226.

The nonvolatile programmable switch element of the present invention according to the second embodiment described above has four terminals, and includes a first electrode 102 and a second electrode 226, a third electrode 224, and a fourth electrode. 228 is a completely separated structure. Accordingly, the programmable switch element of the present invention is completely separated from the read-only electrodes (read-only terminals 224 and 228) and the write-only electrodes (write-only terminals 102 and 226) even in the situation where a current or voltage is applied. Device retention characteristics can be improved.

Next, an operation process of the nonvolatile programmable switch device of FIG. 2 will be described in more detail.

First, the write operation will be described. A current or voltage is applied to the first electrode 102 or the second electrode 226, and the heating electrode 108 is Joule heated by the applied current or voltage, thereby heating the phase change layer 210. . When the heated phase change layer 210 is quenched after the temperature rises above the melting point, it is written off as an amorphous state of high resistance, and is lowered when the phase change layer 210 rises above the crystallization temperature and below the melting point temperature, It is written in the on state as the determination state of the resistance. Due to the characteristics of the phase change layer 210, the resistance state is maintained even if the power is turned off.

Next, the read operation will be described. For the read operation, the metal layer 212a positioned on the left and right sides of the phase change layer 210, the third electrode 224, and the fourth electrode 228 connected thereto are used. When the resistance value of the phase change layer 210 is high, it is read off, and when the resistance value of the phase change layer 210 is low, it is read on.

3 is a cross-sectional view of the chalcogenide storage element for comparison with FIG. 1.

Specifically, the chalcogenide storage device of the comparative example of FIG. 2 is a view shown in Korean Patent Application Publication No. 2006-0121895 filed on April 5, 2006 by an energy convergence device, INC. The chalcogenide storage device of the comparative example includes a silicon wafer 310, a lower terminal 330 including a lower metal electrode 340 on the thermal oxide 320, and an upper terminal 390 including an upper metal electrode 410. And an intermediate terminal 370 including side metal electrodes connected to the GST phase change layer 380. The intermediate terminal 370 configured as the side metal electrode is made of the same metal material as the lower metal electrode 340 and the upper metal electrode 410. In Fig. 3, reference numerals 350 and 400 denote barrier layers, 360 denote insulating regions, and 420 denote aluminum layers.

Unlike the chalcogenide storage device of FIG. 3, the nonvolatile programmable switch device of the present invention has a four-terminal structure, and includes a write-only first electrode 102 and a second electrode 130 and 226, and a read-only third electrode ( 128 and 224 and the fourth electrodes 132 and 228 are completely removable. That is, the chalcogenide storage device of the comparative example of FIG. 3 does not have a structure in which the read and write electrodes are completely separated. In addition, the production method is also different from the present invention.

In the case of the device of FIG. 3 having only two or three electrodes (terminals), at least one terminal must perform both a write operation and a read operation. In this case, a failure is likely to occur when the retention test in the bias application situation, which is one of the electrical characteristic specifications of the switch element, is performed. However, the device of the present invention completely separates an electrode (terminal) during a write operation and a read operation. Therefore, the nonvolatile programmable switch element of the present invention can achieve an improvement in reliability such as retention even in a bias application situation.

4 to 7 are cross-sectional views illustrating a method of manufacturing the nonvolatile programmable switch device of FIG. 1.

Referring to FIG. 4, the first electrode 102 is formed on the semiconductor substrate 100. The first electrode 102 is formed by depositing a conductive film such as Cu, Al, TiW or W and patterning the same by a photo process and an etching process. As described above, the first electrode 102 is used as a write-only electrode during the operation of the programmable switch element.

The first insulating layer 104 is formed on the first electrode 102 and the semiconductor substrate 100 to cover the first electrode 102. The first insulating layer 104 is formed of an oxide layer or a nitride layer. The first insulating layer 104 is patterned to form a contact hole 106 exposing a portion of the first electrode 102. The heating electrode 108 is formed in the contact hole 106. The heat generating electrode is formed of a Ti-based alloy such as TiN or a SiGe-based alloy.

Referring to FIG. 5, after forming a metal material layer (not shown) and an insulating material layer (not shown) on the heating electrode 108 and the first insulating layer 104, the metal material layer and the insulating material layer are patterned. Thereby forming a pore 110 exposing the heating electrode 108. Accordingly, the metal layer 112 and the second insulating layer 114 having the pores 110 exposing the heating electrode 108 are formed on the heating electrode 108 and the first insulating layer 104. Subsequently, the phase change material layer 116 is formed on the second insulating layer 114 to contact the heating electrode 108 and the metal layer 112 while filling the pore 110.

Referring to FIG. 6, the phase change material layer 116 is planarized to the etch stop point of the second insulating layer 114 to form a phase change layer 118 in the pore. The surface of the second insulating layer 114 is exposed by planarization of the phase change material layer 116. Planarization of the phase change material layer 116 is performed using a chemical mechanical polishing process.

Referring to FIG. 7, an insulating material layer (not shown) is formed on the phase change layer 118 and the second insulating layer 114. The insulating material layer is formed of an oxide layer or a nitride layer. Subsequently, the insulating material layer and the second insulating layer 114 are patterned to form the patterned third insulating layer 120 and the patterned second insulating layer 114a. Accordingly, the first via hole 122 and the third via hole 126 are formed around the phase change layer 118 on the metal layers 112 on both sides of the phase change layer 118, and the phase change layer 118 is formed on the phase change layer 118. The second via hole 124 is formed in the second via hole 124.

Subsequently, a conductive film such as a Cu, Al, TiW, or W film is formed to fill the first via hole 122, the second via hole 124, and the third via hole 126, and then patterned by a photo process and an etching process. As shown in FIG. 1, the third electrode 122, the fourth electrode 126, and the second electrode 124 are formed. The third electrode 122 and the fourth electrode 126 are connected to the metal layer 112.

 The third electrode 122 and the fourth electrode 126 are used as read-only electrodes in the operation of the programmable switch element. The second electrode 124 is formed on the phase change layer 118 and is connected to the phase change layer 118. The second electrode 124 is used as a write-only electrode in the operation of the programmable switch element.

8 to 11 are cross-sectional views illustrating a method of manufacturing the nonvolatile programmable switch device of FIG. 2.

Referring to FIG. 8, the first electrode 102, the first insulating layer 104, and the heating electrode 108 are formed on the semiconductor substrate 100 in the same manner as in FIG. 4. A phase change layer 210 connected to the heating electrode 108 is formed on the heating electrode 108 and the first insulating layer 104. The phase change layer 210 is formed by patterning a phase change material layer (not shown) on the heating electrode 108 and the first insulating layer 104.

Referring to FIG. 9, a metal material layer 212 is formed on the entire surface of the semiconductor substrate 100 on which the phase change layer 210 and the first insulating layer 104 are formed. The metal material layer 212 is formed on the first insulating layer 104 while covering and contacting the phase change layer 210. An insulating material layer 214 is formed on the metal layer material layer 212.

Referring to FIG. 10, the insulating material layer 214 and the metal material layer 212 are planarized by using the upper surface of the phase change layer 210 as an etch stop. Accordingly, the surfaces of the phase change layer 210 and the insulating material layer 214 are exposed. The metal material layer 212 becomes the metal layer 212a formed on the first insulating layer 104 while in contact with both sides of the phase change layer 210. The insulating material layer 214 is formed on the metal layer 212a with the insulating material layer pattern 214a. Planarization of the insulating material layer 214 and the metal material layer 212 is performed using a chemical mechanical polishing process. Subsequently, a third insulating layer 216 is formed on the phase change layer 210, the metal layer 212a, and the insulating material layer pattern 214a.

Referring to FIG. 11, the third insulating layer 216 and the insulating material layer pattern 214a are patterned to form a patterned third insulating layer 216a and a second insulating layer 214b. Accordingly, the first via hole 218 and the third via hole 222 are formed around the phase change layer 210 on the metal layers 212a on both sides of the phase change layer 210, and the phase change layer 210 is formed. The second via hole 220 is formed on the second via hole 220.

Subsequently, a conductive film such as a Cu, Al, TiW, or W film is formed to fill the first via hole 218, the second via hole 220, and the third via hole 222, and then patterned by a photo process and an etching process. As shown in FIG. 2, the third electrode 224, the fourth electrode 228, and the second electrode 226 are formed. The third electrode 224 and the fourth electrode 228 are connected to the metal layer 212a. The third electrode 224 and the fourth electrode 228 are used as read-only electrodes in the operation of the programmable switch element. The second electrode 226 is formed on the phase change layer 210 and connected to the phase change layer 210. The second electrode 226 is used as a write-only electrode in the operation of the programmable switch element.

The programmable switch element of the present embodiments described above preferably comprises the third electrodes 128 and 224 and the fourth electrodes 132 and 228 as read-only electrodes (read-only terminals), and the first electrode 102. And the second electrodes 130 and 226 as write-only electrodes (write-only terminals 102 and 130).

However, the first to fourth electrodes may be used for various purposes as long as the current or voltage is applied to the phase change layers 118 and 210 through the heating electrode 108 to form an amorphous state and a crystalline state. For example, the third electrode 128 and 224 and the fourth electrode 132 and 228 are composed of write only electrodes (write only terminals), and the first electrode 102 and the second electrode 130 and 226 are formed. It may also be configured as read-only electrodes (read-only terminals).

1 is a cross-sectional view of a nonvolatile programmable switch device according to a first embodiment of the present invention.

2 is a cross-sectional view of a nonvolatile programmable switch device according to a second embodiment of the present invention.

3 is a cross-sectional view of the chalcogenide storage element for comparison with FIG. 1.

4 to 7 are cross-sectional views illustrating a method of manufacturing the nonvolatile programmable switch device of FIG. 1.

8 to 11 are cross-sectional views illustrating a method of manufacturing the nonvolatile programmable switch device of FIG. 2.

Claims (10)

A first electrode formed on the semiconductor substrate; An insulating layer having a contact hole exposing a part of the first electrode on the first electrode; A heating electrode embedded in the contact hole; A phase change layer formed on the heating electrode; Metal layers in contact with both sides of the phase change layer; A second electrode connected to the phase change layer and insulated from the metal layer; A third electrode connected to one side of the metal layer around the phase change layer; And And a fourth electrode connected to the other side of the metal layer around the phase change layer. The nonvolatile programmable switch device of claim 1, wherein the metal layer is formed in contact with a portion of the side surface of the phase change layer, or is formed in contact with all of the side surfaces of the phase change layer. The method of claim 1, wherein the first electrode and the second electrode is a write-only electrode, the third electrode and the fourth electrode is a read-only electrode for detecting the resistance value of the phase change layer through the metal layer. Nonvolatile programmable switch element. The semiconductor device of claim 1, further comprising: a first via hole and a third via hole exposing one side portion and the other side portion of the metal layer around the phase change layer, and a second insulating layer having a second via hole on the phase change layer; And a third insulating layer, wherein the third electrode and the fourth electrode are embedded in the first via hole and the third via hole, respectively, and the second electrode is formed in the second via hole. Volatile programmable switch element. The nonvolatile programmable switch device of claim 1, wherein the first electrode and the second electrode are electrically separated from the third electrode and the fourth electrode. Forming a first electrode on the semiconductor substrate; Forming a first insulating layer having a contact hole exposing the first electrode; Forming a heating electrode embedded in the contact hole; Forming a phase change layer on the heating electrode; Sequentially forming metal layers and second insulating layers on both sides of the phase change layer; Forming a third insulating layer on the second insulating layer and the metal layer to cover the phase change layer; And The third insulating layer and the second insulating layer are patterned to form third and fourth electrodes, respectively, on one side and the other side of the metal layer around the phase change layer, and a second electrode on the phase change layer. A method of manufacturing a nonvolatile programmable switch device, characterized in that it is formed. The method of claim 6, wherein the phase change layer, Forming the metal layer and the second insulating layer having pores exposing the heating electrode on the heating electrode and the first insulating layer, and forming a phase change material layer in contact with the heating electrode and the metal layer while filling the pore; And planarizing the phase change material layer by using the second insulating layer as an etch stop layer to fabricate the nonvolatile programmable switch device. The method of claim 6, wherein the phase change layer, the metal layer and the second insulating layer, Forming the phase change layer on the heating electrode and the first insulating layer; Forming a metal material layer and an insulating material layer on the first insulating layer to cover the phase change layer; And forming the metal layer and the second insulating layer by planarizing the insulating material layer and the metal material layer by using the phase change layer as an etch stop layer. The method of claim 6, wherein the third electrode, the second electrode and the fourth electrode, Patterning the third insulating layer and the second insulating layer to form first via holes and third via holes on the metal layers on both sides of the phase change layer, and form second via holes on the phase change layer; And And a third electrode, a second electrode, and a fourth electrode embedded in the first via hole, the second via hole, and the third via hole, respectively. 7. The non-limiting method of claim 6, wherein the third electrode and the fourth electrode are read-only electrodes when the programmable switch element is operated, and the first and second electrodes are write-only electrodes when the programmable switch element is operated. Method of manufacturing volatile programmable switch device.

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