阅读说明：本技术 一种ots材料、选通器单元及其制备方法 (OTS material, gating unit and preparation method thereof ) 是由 武仁杰 朱敏 贾淑静 宋志棠 于 2020-04-10 设计创作，主要内容包括：本发明涉及一种OTS材料、选通器单元及其制备方法。该OTS材料的化学通式为Ga<Sub>x</Sub>S<Sub>1-x-y</Sub>R<Sub>y</Sub>。该选通器单元包括该OTS材料。该选通器单元在外部电激励的作用下,能够实现从关断的、高电阻态到导通的、低电阻态的快速转变；而且,在撤去外部电激励时,能够由导通的、低电阻态向关断的、高电阻态快速转变；并且该选通器单元具有驱动电流高、阈值电压较低、开启速度快、开关比大、热稳定性好等优点。(The invention relates to an OTS material, a gating unit and a preparation method thereof. The OTS material has a chemical general formula of Ga x S 1‑x‑y R y . The gate unit includes the OTS material. The gate unit can realize rapid transition from an off state with high resistance to an on state with low resistance under the action of external electric excitation; moreover, when the external electric excitation is removed, the switch can be quickly switched from a conducting low-resistance state to a switching-off high-resistance state; the gate unit has the advantages of high driving current, lower threshold voltage, high starting speed, large switching ratio, good thermal stability and the like.)

1. An OTS material is provided, which comprises a base material,characterized in that the chemical general formula of the material is Ga_xS_1-x-yR_y0.333 in the formula<x<0.667, y is 0 to 0.55, R is an element other than Ga and S.

2. The material of claim 1, wherein R is one or more of As, C, N, Si, Ge, S, Se, Te and Sb.

3. The material of claim 1, wherein the material is Ga_0.45S_0.55、Ga_0.45S_0.05N_0.5Or Ga_0.42As_0.06S_0.52。

4. A method of manufacturing an OTS material as claimed in claim 1, wherein the OTS material is manufactured by sputtering, evaporation, physical vapor phase, chemical vapor phase, molecular beam epitaxy, atomic vapor deposition or atomic layer deposition.

5. A gate cell, characterized in that the cell comprises the OTS material of claim 1.

6. The unit according to claim 5, characterized in that it comprises, in sequence from bottom to top: the device comprises a lower electrode layer, an OTS material layer, an upper electrode layer and a lead-out electrode.

7. The cell of claim 6, wherein the upper electrode layer has a thickness of 10nm to 50 nm; the thickness of the OTS material layer is 1 nm-100 nm.

8. The cell of claim 6, wherein the extraction electrode has a thickness of 100nm to 500 nm.

9. The unit of claim 6, wherein the material of the lower electrode layer, the upper electrode layer and the extraction electrode comprises one or more of metal simple substances of W, Pt, Au, Ti, Al, Ag, Cu, Ni and nitrides thereof.

10. A method of making the cell of claim 5, comprising:

(1) preparing a lower electrode layer;

(2) preparing a gating material layer on the lower electrode layer in the step (1), wherein the gating material layer is made of an OTS material;

(3) preparing an upper electrode layer on the gating material layer in the step (2);

(4) and (4) preparing an extraction electrode on the upper electrode layer in the step (3).

Technical Field

The invention belongs to the technical field of microelectronics, and particularly relates to an OTS material, a gate unit and a preparation method thereof.

Background

Phase Change Random Access Memory (PCRAM) is a new type of nonvolatile memory, and has become the most competitive next generation memory technology due to its advantages such as high density (scalability), high speed, and low power consumption.

In order to achieve the goal of high density storage, the most popular approach is to use a crossbar array. The crossbar array requires the integration of gates with the gating cells. The role of the gate among them is: under the action of an external electric field, when a threshold voltage is reached, the transition from a high-resistance state to a low-resistance state can be realized, and the gate is opened. When the voltage is lower than the holding voltage, the state can be changed from the low resistance state to the high resistance state, and the gate is turned off. Based on the characteristics, the gate tube can effectively avoid the crosstalk problem caused when the information of the storage unit is read.

Currently, a gate tube capable of realizing three-dimensional integration mainly comprises an oxide diode, an oxide triode, a threshold change switch and the like. However, the gating device made of the material generally has the phenomena of higher threshold voltage and poorer thermal stability. In addition, for new memory devices such as phase change memory, the drive current is required to be at MA/cm²On-state currents of such high magnitude are difficult to achieve with typical gated devices. Therefore, the development of the gate device is currently aimed at achieving a large driving current, a high switching ratio, a low threshold voltage, high fatigue, and high reliability.

Disclosure of Invention

The invention aims to solve the technical problem of providing an OTS material, a gate unit and a preparation method thereof, so as to overcome the defects of low driving current, small switching ratio, high threshold voltage, poor thermal stability and the like of a gate in the prior art.

The invention also provides an OTS material, and the chemical general formula of the material is Ga_xS_1-x-yR_yIn the formula 0<x<1 (preferably 0.333)<x<0.667), y is 0 to 0.55, R is an element other than Ga and S.

And R is one or more of As, C, N, Si, Ge, S, Se, Te and Sb.

The material is Ga_0.45S_0.55、Ga_0.45S_0.05N_0.5Or Ga_0.42As_0.06S_0.52。

The OTS material can realize rapid transition from a high resistance state to a low resistance state when an applied voltage exceeds a threshold voltage, and can transition from the low resistance state to the high resistance state when the voltage is lower than a holding voltage.

The invention also provides a preparation method of the OTS material, which adopts a sputtering method, an evaporation method, a physical vapor phase method, a chemical vapor phase method, a molecular beam epitaxy method, an atomic vapor phase deposition method or an atomic layer deposition method to prepare the OTS material.

The invention also provides a gate unit comprising the OTS material.

The unit includes from bottom to top in proper order: the device comprises a lower electrode layer, an OTS material layer, an upper electrode layer and a lead-out electrode.

The thickness of the upper electrode layer is 10 nm-50 nm.

The thickness of the OTS material layer is 1 nm-100 nm; the thickness of the extraction electrode is 100 nm-500 nm.

The materials of the lower electrode layer, the upper electrode layer and the extraction electrode comprise one or more of metal simple substances W, Pt, Au, Ti, Al, Ag, Cu, Ni and nitrides thereof.

The invention also provides a preparation method of the gate unit, which comprises the following steps:

(1) preparing a lower electrode layer;

(2) preparing a gating material layer on the lower electrode layer in the step (1), wherein the gating material layer is made of an OTS material;

(3) preparing an upper electrode layer on the gating material layer in the step (2);

(4) and (4) preparing an extraction electrode on the upper electrode layer in the step (3).

The preparation method of the lower electrode layer, the gating material layer, the upper electrode layer and the extraction electrode comprises the following steps: physical vapor deposition, chemical vapor deposition, electron beam evaporation, molecular beam epitaxy, or atomic layer deposition.

The upper electrode layer, the lower electrode layer and the gate material layer are integrated with other elements such as a memory cell, a driving circuit and a peripheral circuit through the extraction electrode.

Advantageous effects

The invention is based on Ga_xS_1-x-yR_y(0<x<1, y is 0-0.55), can realize the quick transition from the off, high resistance state to the on, low resistance state under the effect of external electric excitation. Moreover, when the external electric excitation is removed, the resistance state can be switched from the on-state, low-resistance state to the off-state, high-resistance stateAnd (4) rapidly converting. The gating unit based on the chalcogenide compound has the advantages of high driving current, lower threshold voltage, high starting speed, large switching ratio, good thermal stability and the like.

Drawings

Fig. 1 is a graph of the threshold switching characteristics, i.e., the current-voltage (I-V) measured under voltage excitation, of a gate cell based on the gate material of the present invention.

Fig. 2 is a graph representing the switching speed of a gate unit based on the gate material of the present invention.

Fig. 3 is a graph of fatigue characteristics of a gating cell based on the gating material of the present invention.

Figure 4 is an XRD pattern based on different temperatures of the gated material of the present invention.

Detailed Description

The invention will be further illustrated with reference to the following specific examples. It should be understood that these examples are for illustrative purposes only and are not intended to limit the scope of the present invention. Further, it should be understood that various changes or modifications of the present invention may be made by those skilled in the art after reading the teaching of the present invention, and such equivalents may fall within the scope of the present invention as defined in the appended claims. It is to be noted that the features in the following embodiments and examples may be combined with each other without conflict.