CN100369188C - Fabrication method of image charge effect quantum cellular automaton - Google Patents

Abstract

A method for making an image charge effect quantum cellular automaton is characterized in that it comprises the following steps: forming an insulating layer whose thickness can be controlled on a substrate; On the substrate; use intelligent cutting or grinding to thin the semiconductor layer to a thickness below 100nm; according to the requirements of quantum cellular automaton devices and circuits, use etching technology to etch the semiconductor layer into a quantum dot array, the The quantum dot array includes a plurality of cellular units, and each cellular unit includes four quantum dots; oxidation and deposition processes are used to form an oxide layer around the quantum dots to make a mirror charge effect quantum cellular automaton. There are two electrons; using the scanning tunneling electron microscope and the atomic force microscope, injecting additional electrons, when the electrons are injected, an equal amount of mirror positive charges will be formed on the substrate at the same time.

Description

Fabrication method of image charge effect quantum cellular automaton

technical field

The present invention designs a method for manufacturing a mirror image charge effect quantum cellular automaton, especially a method for forming an insulating layer with a controllable thickness such as two layers on a substrate with high conductivity such as a metal substrate or a highly doped semiconductor substrate. Silicon oxide (SiO ₂ ), etc., use wafer bonding technology to bond semiconductor wafers such as silicon (Si) to a substrate with high conductivity with an insulating layer, and use a thinning process to thin the semiconductor to below 100nm Thickness, according to the requirements of quantum cellular automaton devices and circuits, the semiconductor thin layer is etched into an array of quantum dots by etching technology, and an oxide layer is formed around the quantum dots by oxidation and deposition processes to form a mirror charge effect quantum cell Automata technology; suitable for mirror charge effect quantum cellular automata devices and circuits.

Background technique

In the past few decades, the integration of microelectronic integrated circuits has become higher and higher. With the continuous shrinking of its characteristic line width, the characteristics of transistors are close to their physical limits, and the quantum effects are more significant, which makes the development of integrated circuits Encountered an insurmountable bottleneck. In order to overcome the above problems and use quantum mechanical effects to develop new devices and circuits, Lent proposed a new computing model - the concept of quantum cellular automaton (Quantum cellular automaton, referred to as QCA). Quantum cellular automaton utilizes the close-range interaction between cells to realize information transmission and logic operations. It can avoid the problem of long-distance wiring difficulties in large-scale integrated circuits. At the same time, it has high speed, low power consumption, and high integration. Features. In recent years, more and more attention has been paid to the research of QCA, many specific implementation schemes have been proposed, and small-scale QCA logic circuits have been verified experimentally. Among them, the image charge effect quantum cellular automata (QCA) proposed by us is one of the most feasible schemes. An outstanding advantage of image charge QCA compared with other QCAs is that it is easy to achieve the charge neutrality of the entire device structure, and the tunneling effect of quantum mechanics can be used to inject two remaining working charges into each cell. Although the structure scheme of image charge effect QCA has been proposed, but so far there is no complete set of process methods for realizing image charge effect QCA.

Contents of the invention

The purpose of the present invention is to provide a manufacturing method of mirror charge effect quantum cellular automata, which has the advantage of adopting the method of combining standard semiconductor technology and nano-processing technology, which can realize mirror charge effect quantum cellular automata devices and circuits .

In order to achieve the above object, the present invention adopts the following technical solutions:

The present invention is a kind of manufacturing method of image charge effect quantum cellular automaton, is characterized in that, comprises the following steps:

1) Forming an insulating layer with a controllable thickness on the substrate;

2) Bonding the semiconductor layer to the substrate with the insulating layer by a wafer bonding process;

3) Thin the semiconductor layer to a thickness below 100nm by using intelligent cutting or grinding processes;

4) According to the requirements of the quantum cellular automaton device and circuit, the semiconductor layer is etched into a quantum dot array by an etching process, the quantum dot array includes a plurality of cellular units, and each cellular unit includes four quantum dots;

5) Oxidation and deposition processes are used to form an oxide layer around the quantum dots to form a mirror charge effect quantum cellular automaton, with two electrons in each cell;

6) Using the scanning tunneling electron microscope and the atomic force microscope to inject additional electrons, when the electrons are injected, an equal amount of mirror positive charges will be formed on the substrate at the same time.

The substrate is a substrate with high conductivity, which is a metal material or a highly doped semiconductor material, on which various processes can be processed.

The insulating layer on the substrate is an oxide layer or a nitride layer, which is formed by high-temperature oxidation or deposition. The temperature and time can be adjusted according to the requirements of the image charge effect quantum cellular automaton device and circuit. parameter to get the thickness of the corresponding insulating layer.

Wherein the semiconductor layer is a Si, GaAs semiconductor single wafer or a semiconductor with a superlattice structure, which is bonded to the insulating layer of the substrate by a bonding method.

The quantum dot array is formed by nano-growth processing technologies such as electron beam exposure and ion etching. The quantum dots are columnar or hemispherical. The size and spacing of quantum dots are processed according to the requirements of mirror charge effect quantum cellular automaton devices. .

The oxide layer after the formation of the quantum dot array is formed by high temperature oxidation plus oxide layer deposition or simply oxide layer deposition according to the type of semiconductor.

Description of drawings

In order to further illustrate the technology of the present invention, the following detailed descriptions are as follows in conjunction with the embodiments and accompanying drawings, wherein:

Fig. 1 is a schematic diagram of the structure of the image charge effect quantum cellular automata device.

Fig. 2 is a process flow chart of making the image charge effect quantum cellular automaton.

Detailed ways

Please refer to Figure 1 and Figure 2,

Please refer to Fig. 1, Fig. 1 shows a schematic diagram of the structure of the image charge effect quantum cellular automaton. It is composed of a substrate 101 , an insulating layer 102 , semiconductor quantum dots 104 , and an oxide layer 103 formed around the quantum dots 104 . The material of the substrate 101 is a metal material. A silicon dioxide (SiO ₂ ) insulating layer 102 with a controllable thickness can be formed on the substrate 101 . A semiconductor layer 108 (silicon (Si) wafer) may be bonded to a metal substrate 101 with a silicon oxide (SiO ₂ ) insulating layer 102 using a wafer bonding process. Then, the semiconductor layer (108) can be thinned to a thickness below 100 nm by using a smart cut process. The thin layer of the semiconductor layer 108 can be etched into a whole column of quantum dots 104 according to the requirements of quantum cellular automaton devices and circuits by using an etching process. Four quantum dots form a cell 106, and each cell has two electrons. 105 , correspondingly there will be two image charges 107 in the metal substrate 101 . Finally, a SiO ₂ oxide layer 103 is formed around the quantum dots by high temperature oxidation and oxide layer deposition process, and the image charge effect quantum cellular automaton can be made.

Please refer to Fig. 2, a kind of preparation method of image charge effect quantum cellular automaton of the present invention, comprises the following steps:

1) Form an insulating layer 102 with a controllable thickness on the substrate 101 (FIG. 2a); the substrate 101 is a substrate with high conductivity, which is a metal material or a highly doped semiconductor material, on which various processes can be performed processing;

2) the semiconductor layer 108 is bonded to the substrate 101 with the insulating layer 102 (Fig. 2b) by a wafer bonding process; the semiconductor layer 108 is a Si, GaAs semiconductor single wafer or a semiconductor with a superlattice structure, Bonding to the insulating layer 102 of the substrate 101 by a bonding method;

3) Thinning the semiconductor layer 108 to a thickness below 100nm by using processes such as intelligent cutting or grinding (FIG. 2c);

4) According to the requirements of the quantum cellular automaton device and circuit, the semiconductor layer 108 is etched into a quantum dot array by using an etching process. The quantum dot array includes a plurality of cellular units 106, and each cellular unit 106 includes four quantum dots. Dot 104 (Fig. 2d); wherein the quantum dot array is formed by nano-growth processing technologies such as electron beam exposure plus ion etching, the quantum dot 104 is columnar or hemispherical, and the size of the quantum dot 104 and the spacing of the quantum dot 104 are based on the image charge effect Quantum cellular automaton device requirements for processing;

5) Oxidation and deposition processes are used to form an oxide layer 103 (Fig. 2e) around the quantum dot 104 to make a mirror image charge effect quantum cellular automaton, with two electrons 105 in each cell; Oxide layer 103 is formed by high-temperature oxidation method, or formed by deposition method, and the thickness of corresponding oxide layer 103 can be obtained by adjusting parameters such as temperature and time according to the requirements of image charge effect quantum cellular automaton device and circuit;

6) Using a scanning tunneling electron microscope and an atomic force microscope to inject additional electrons, when the electrons are injected, an equal amount of mirror positive charges 107 will be simultaneously formed on the substrate 101 ( FIG. 2 e ).

Example

Please refer to FIG. 2 again. FIG. 2 shows a schematic diagram of the fabrication process of the mirror charge cellular automaton device. First, as shown in (a) of FIG. 2 , a silicon dioxide (SiO ₂ ) insulating layer 102 is deposited on the metal substrate 101, and the temperature can be adjusted according to the requirements of the image charge effect quantum cellular automaton device. Time and other parameters to get the thickness of the corresponding oxide layer.

Then, as shown in (b) of FIG. 2 , the semiconductor layer 108 (Si wafer) can be bonded on the SiO ₂ insulating layer 102 by a wafer bonding process. Then, the semiconductor layer 108 is thinned to a thickness below 100 nm by using a smart cut process, and the result shown in (c) of FIG. 2 is obtained.

Next, according to the structure of the image charge effect quantum cellular automaton device we want to obtain, the array of Si quantum dots 104 is formed, as shown in FIG. 2( d ). The array of quantum dots 104 can be formed by nano-growth processing technologies such as electron beam exposure plus ion etching. These quantum dots 104 can be in the shape of columns or hemispheres. The distance between them and the quantum dots 104 can be obtained by etching or growing according to our actual needs. In the quantum dot 104, additional electrons can be injected using a scanning tunneling electron microscope (STM) and an atomic force microscope (AFM). After the electrons are injected, an equal amount of mirrored positive charges 107 will be formed on the metal substrate at the same time, thereby maintaining the charge neutrality of the entire QCA circuit.

Finally, as shown in FIG. 2( e ), after the quantum dots 104 array is formed, an oxide layer 103 needs to be formed around the quantum dots 104 . The oxide layer 103 can be formed by a method of high temperature oxidation plus oxide layer deposition or a simple oxide layer deposition method according to the type of semiconductor. This oxide layer acts as a tunneling barrier.

Through the above process, the device structure of the quantum cellular automaton utilizing the image charge 107 effect can be realized.

Claims (7)

1. A method for making a mirror image charge effect quantum cellular automaton, characterized in that it comprises the following steps: 1) Forming an insulating layer with a controllable thickness on the substrate; 2) Bonding the semiconductor layer to the substrate with the insulating layer by a wafer bonding process; 3) Thin the semiconductor layer to a thickness below 100nm by using intelligent cutting or grinding processes; 4) According to the requirements of the quantum cellular automaton device and circuit, the semiconductor layer is etched into a quantum dot array by an etching process, the quantum dot array includes a plurality of cellular units, and each cellular unit includes four quantum dots; 5) Oxidation and deposition processes are used to form an oxide layer around the quantum dots to form a mirror charge effect quantum cellular automaton, with two electrons in each cell; 6) Using a scanning tunneling electron microscope and an atomic force microscope, inject additional electrons into the quantum dots. When the electrons are injected, an equal amount of mirror positive charges will be formed on the substrate at the same time. 2. The manufacturing method of the image charge effect quantum cellular automaton according to claim 1, wherein the substrate is a substrate of high conductivity, is a metal material, and can be processed by various processes thereon. 3. the manufacture method of image charge effect quantum cellular automata according to claim 1, is characterized in that, wherein substrate is the substrate of high conductivity, is highly doped semiconductor material, can carry out various processes above processing. 4. the manufacture method of mirror image charge effect quantum cellular automata according to claim 1 is characterized in that, wherein the oxide layer on the insulating layer is formed by high temperature oxidation, or forms with the method of deposition, according to image charge effect According to the requirements of quantum cellular automaton devices and circuits, adjust the temperature and time parameters to obtain the corresponding oxide layer thickness. 5. the manufacture method of image charge effect quantum cellular automata according to claim 1, is characterized in that, wherein semiconductor layer is Si, GaAs semiconductor monolithic wafer or the semiconductor with superlattice structure, bonds by bonding method bonded to the insulating layer of the substrate. 6. The manufacturing method of image charge effect quantum cellular automata according to claim 1, wherein the quantum dot array is formed by electron beam exposure plus ion etching nano-growth processing technology, and the quantum dots are columnar or hemispherical , the size of the quantum dots and the spacing of the quantum dots are processed according to the requirements of the image charge effect quantum cellular automaton device. 7. according to the manufacture method of claim 1 or 6 described image charge effect quantum cellular automata, it is characterized in that, wherein the oxide layer after the quantum dot array is formed adopts the deposition of high temperature oxidation plus oxide layer according to the kind of semiconductor method of formation or pure oxide layer deposition method.

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