Semiconductor devices formed using conductive materials deposition on semiconductor to generate phase change and

Abstract

The present invention provides a method of depositing a photon-induced conductive material on a substrate, comprising the steps of: preparing a first solution comprising a metal salt, a metal ion, or a combination thereof; preparing a first suspension comprising the nanoparticles, a photosensitive reducing agent, an electron donor solvent, or a combination thereof; mixing the first solution and the first suspension to form a first reagent on the first substrate; a light beam provided by a light source is emitted and focused onto a first reagent held on a first region of a first substrate having a second region exposed to an ambient gas or air environment, thereby forming a mechanically rigid conductive deposit in contact with the first substrate at the focal point of the light source.

Description

Technical Field

[0001] The technology involved in the present invention is a semiconductor structure and a manufacturing method thereof. More specifically, the semiconductor structure / device and the manufacturing method thereof involved in the present invention is a method of depositing a conductive material on a semiconductor to produce a phase change and an ohmic contact. Background Art

[0002] Devices in the microelectronics and display industries rely on the patterning of conductive materials on semiconductors to create microcircuits on flexible and rigid substrates. The primary methods for generating these patterns are thin-film and etching methods, which are used to create conductive features smaller than about 100 microns. For lower-resolution applications, the most common methods include: fused deposition modeling (FDM), PolyJet printing, direct ink writing (DIW), stereolithography (SLA) / digital light processing (DLP), selective laser sintering (SLS), and direct laser writing (DLW).

[0003] Although a few methods show the potential of precision deposition technology, the processes involved are too complicated, time-consuming, or too expensive. More importantly, these methods usually impose additional requirements on design, samples, workspace, and manpower. In this regard, direct laser writing provides a possible solution to overcome the above problems.

[0004] As the scaling of devices approaches its limits, the related field is exploring innovative materials for silicon to keep the expansion of Moore's Law. Among the recently introduced two-dimensional materials, especially the atomically thin semiconductor transition metal dichalcogenides (TMDs), such as molybdenum disulfide (MoS2), tungsten diselenide (WSe2) and molybdenum ditelluride (MoTe2), have become the game changers of the current MOSFET scaling technology. As the channel material of field effect transistors (FETs), TMDs provide dangling bond free surfaces, high thermal stability and significantly tunable band gaps, which show immunity to short channel effects and become the potential materials for the next revolution in mainstream chip manufacturing.

[0005] On the other hand, due to the ultra-thin structure and fine lattice of 2D materials, obtaining high-quality metal-semiconductor (MS) contacts on 2D materials remains a key challenge. The contact surface controls the efficiency of carrier injection from metal to 2D channels. Large Schottky barriers can seriously degrade the performance of field-effect transistors, such as current on / off ratio, field-effect mobility, and drain current. Without ohmic contacts, tunneling effects in high-speed circuits delay response. However, due to many strict conditions, such as neat contact between metal and 2D materials and Fermi level pinning effects, the pursuit of pure non-rectifying ohmic contacts is somewhat difficult in practice. After the rapid development of 2D materials, this research direction has attracted attention. In order to eliminate the large barrier height, various attempts have been made in related research: low work function metals, ultra-high vacuum evaporation, doping, edge contacts, etc. Although these efforts have reduced the contact resistance to acceptable levels, such as hundreds of ohms per micron, it is still much higher than the ideal resistance of ohmic contacts; and, as you can imagine, they all require complex processes or harsh environmental conditions, or cannot adapt to small sizes less than 100 microns. More importantly, it often places additional demands on sample and functional temperature, resulting in possible material destruction or complete change of properties, or the need for metals with higher resistivity.

[0006] One of the key challenges is to find a mechanism that can achieve ohmic contacts on 2D materials. The mechanism must be broadly general enough to be applied to common metals and 2D materials on many types of substrates. In modern silicon-based device applications, metal electrodes are fabricated on degenerately doped n++ or p++ regions to manipulate the source and drain contacts and the channel type. The higher conductivity state of the channel material helps to limit the mismatch of the Fermi level at the interface, the injection of charge carriers and the reduction of contact resistance. Similar strategies can be applied to 2D materials, but doping is challenging due to their atomically thin nature and the problems they face instability.

[0007] The common method to achieve ohmic contact at the MS interface is to form a phase change on the semiconductor, which can be achieved by applying stress, plasma electron doping, chemical reaction, argon plasma and alkali metal ion doping, etc. However, most of these methods face the problem of being unable to form a phase change locally to maintain the original properties of the channel, and these methods usually require non-general environmental conditions such as alkalinity or high pressure. These problems also limit the practical application of phase change method in achieving ohmic contact.

[0008] Therefore, an improved method is needed, that is, depositing a conductive material on the surface of a semiconductor substrate having an ohmic contact through an in-situ phase change, and also being able to conveniently perform direct testing on the semiconductor sample, so as to overcome the above problems. Summary of the invention

[0009] The object of the present invention is to provide a semiconductor structure and a method thereof to solve the above-mentioned problems existing in the prior art.

[0010] In the present invention, the solution involves the deposition of materials that can be used to produce conductive features and patterns. An important feature is that direct laser writing is used to deposit conductive materials and simultaneously form ohmic contacts in situ on semiconductors through phase changes. The composition for ohmic contacts can be efficiently deposited on various semiconductors at low temperatures and allows direct testing on single-layer, double-layer or multi-layer semiconductors, as well as the manufacture of diodes, transistors and microcircuits with different functions.

[0011] According to one aspect of the present invention, a method for photon-induced deposition of a conductive material on a substrate is provided. The method comprises the following steps: preparing a first solution, which contains a metal compound, a metal ion or a combination thereof; preparing a first suspension, which contains nanoparticles, a photosensitive reducing agent, an electron donor solvent or a combination thereof; mixing the first solution with the first suspension and forming a first reagent on a first substrate; emitting a light beam, which is provided by a light source and focused onto the first reagent held on a first area of ​​the first substrate to form a mechanically rigid conductive deposit in contact with the first substrate at the focus of the light source, wherein the first substrate has a second area exposed to an ambient gas or air environment.

[0012] According to one aspect of the present invention, a semiconductor device using photon-induced conductive material deposition is provided. The semiconductor device includes a first substrate, a mechanically rigid conductive deposition, and a second substrate. The first substrate has a first region and a second region adjacent to the first region, wherein the first substrate includes molybdenum disulfide (MoS2), molybdenum diselenide (MoSe2), molybdenum ditelluride (MoTe2), tungsten diselenide (WSe2), graphene, a layer with a metal isomer, or a combination thereof, which is used as a two-dimensional material to form at least one channel in the first substrate. The mechanically rigid conductive deposition is formed as a conductive pattern disposed above the first region of the first substrate, wherein the mechanically rigid conductive deposition forms an ohmic contact with the first region of the first substrate and is a solid and rigid composite pattern made of pure metal, solid metal salt, metal oxide, or a combination thereof. The second substrate is attached to the first substrate, wherein the mechanically rigid conductive deposition is located above the first substrate and the second substrate, and also extends from the first region of the first substrate to the second substrate.

[0013] In the present disclosure, a conductive material deposition for making functional patterns with special electrical properties is provided. The material deposition can form an ohmic contact at the metal-semiconductor interface through an in-situ semiconductor phase transition. The material deposition forms a strong adhesion with the substrate, thereby allowing the use of advantageous direct write lasers. The material deposition also has a low conversion temperature, thereby preventing material damage. The nanoparticle composition allows maskless deposition on different substrates. The contact resistance between the deposited metal and the semiconductor is very low, which allows direct measurement of semiconductor electrical properties and is not affected by contact interference and Schottky barriers. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] The embodiments of the present invention will be described in more detail with reference to the accompanying drawings, in which:

[0015] Figure 1A is a top view of a semiconductor device according to some embodiments of the present disclosure;

[0016] Figure 1B yes Figure 1A A vertical cross-section along line I-I';

[0017] Figure 1C yes Figure 1A A vertical cross-section along line II-II';

[0018] Figure 1D is a vertical cross-sectional view of a local structure profile of a first substrate according to some embodiments of the present invention;

[0019] Figure 2A , Figure 2B and Figure 2C is a schematic diagram according to some embodiments of the present disclosure, which illustrates a method of photon-induced deposition of a conductive material on a semiconductor to create an electrode and thereby establish an ohmic contact;

[0020] Figure 2D is a schematic diagram according to some embodiments of the present disclosure, which illustrates a further stage of obtaining one or more electrodes having a desired shape;

[0021] Figure 3A , Figure 3B , Figure 3C and Figure 3D The Raman spectroscopic analysis of the deposition of different noble metals on different TMDs is illustrated according to some embodiments of the present invention;

[0022] Figure 4A , Figure 4B , Figure 4C and Figure 4D Together, electrical measurement graphs of FET devices fabricated using solutions according to some embodiments of the present invention are provided;

[0023] Figure 5 is a vertical cross-sectional view of a semiconductor device according to some embodiments of the present disclosure;

[0024] Figure 6 is a vertical cross-sectional view of a semiconductor device according to some embodiments of the present disclosure;

[0025] Figure 7 is a vertical cross-sectional view of a semiconductor device according to some embodiments of the present disclosure;

[0026] Figure 8 is a vertical cross-sectional view of a semiconductor device according to some embodiments of the present disclosure;

[0027] Fig. 9 is a vertical cross-sectional view of a semiconductor device according to some embodiments of the present disclosure;

[0028] Fig.10 is a vertical cross-sectional view of a semiconductor device according to some embodiments of the present disclosure;

[0029] Fig.11 is a vertical cross-sectional view of a semiconductor device according to some embodiments of the present disclosure;

[0030] Fig.12 is a vertical cross-sectional view of a semiconductor device according to some embodiments of the present disclosure;

[0031] Fig.13 is a vertical cross-sectional view of a semiconductor device according to some embodiments of the present disclosure; and

[0032] Fig.14 is a vertical cross-sectional view of a semiconductor device according to some embodiments of the present disclosure. DETAILED DESCRIPTION

[0033] In the following description, semiconductor structures and methods for depositing conductive materials on semiconductors with phase change and in-situ ohmic contact will be used as preferred examples for explanation. Those skilled in the art will appreciate that modifications, including additions and / or substitutions, may be made without departing from the scope and spirit of the invention. Specific details may be omitted so as not to obscure the invention; however, the present disclosure is written to enable those skilled in the art to practice the teachings herein without undue experimentation.

[0034] In the present disclosure, various embodiments or examples are provided to illustrate different aspects of the subject matter. Specific examples of components and arrangements are included. However, these descriptions are illustrative only and are not intended to be limiting. When describing features, a reference to a first feature being formed on or above a second feature may refer to a situation where the first feature directly contacts the second feature, or to a situation where an additional feature separates them. In addition, for clarity and simplicity, reference numbers or letters may be repeated in the examples, but no relationship between the different embodiments or configurations is implied.

[0035] In this context, to simplify the explanation, terms related to spatial directions, such as "below", "beneath", "lower", "above", "upper", "under", "left", "right" and similar expressions may be used to describe the relationship between one component or feature shown in the figures and another component or feature. In addition to the orientation shown in the figures, these spatial terms are intended to cover various orientations of the device during use or operation. The device can be positioned in different ways (for example, rotating the passivation layer 90 degrees or in other orientations), so the spatial descriptors mentioned here may be applied for clarification. It is worth noting that when a component is described as being "connected" or "coupled" to another component, it can be directly connected or coupled to that component, or intermediate components may be involved.

[0036] In the present disclosure, the terms "approximately", "substantially", "substantially" and "about" are used to describe slight variations. When combined with an event or circumstance, these terms can indicate both the exact and approximate occurrence of the event or circumstance. When used for a specific value or range, "approximately" generally means within ±10%, ±5%, or ±1% of the given value or range. Unless otherwise stated, all ranges mentioned include their endpoints. For example, "substantially coplanar" can mean surfaces that are a few microns (μm) apart from each other along the same plane, such as within 10 μm, 5 μm, or 1 μm.

[0037] Figure 1A is a top view of a semiconductor device 100A according to some embodiments of the present invention; Figure 1B is along Figure 1A A vertical cross-sectional view of line I-I' in FIG. Figure 1C is along Figure 1A The semiconductor device 100A includes a first substrate 110 , a second substrate 120 , and one or more electrodes established by a mechanically rigid conductive deposit 130 .

[0038] In one embodiment, the first substrate 110 includes a semiconductor transition metal dichalcogenides (TMDs) material, such as molybdenum disulfide (MoS2), molybdenum diselenide (MoSe2), molybdenum ditelluride (MoTe2), tungsten diselenide (WSe2), graphene, a layer with metal isomers, or a combination thereof. The TMD material of the first substrate 110 is a two-dimensional material for forming a field effect transistor (FET) channel in the first substrate 110. The first substrate 110 is disposed above the second substrate 120. The first substrate 110 is connected to the second substrate 120; for example, the first substrate 110 is formed or grown from the second substrate 120, so that the second substrate 120 is attached to the first substrate 110. In one embodiment, the second substrate 120 includes glass, quartz, sapphire, indium tin oxide, diamond, silicon, silicon carbide (SiC), silicon oxide, or a combination thereof. The first substrate 110 and the second substrate 120 are not limited to the above materials. In other embodiments, the first substrate 110 or the second substrate 120 may include one or more other features, such as a doped region, a buried layer, an epitaxial (epi) layer, or a combination thereof.

[0039] The mechanically rigid conductive deposit 130 is formed as a conductive pattern (e.g., one or more electrodes) disposed over a first region of the first substrate 110. In this regard, the first substrate 110 includes a first region that is covered by the one or more electrodes and also includes a second region that is adjacent to the first region and is not covered by the one or more electrodes. The mechanically rigid conductive deposit 130 is disposed over the first substrate 110 and the second substrate 120 and extends from the first region of the first substrate 110 to the second substrate 120.

[0040] The mechanically rigid conductive deposit 130 can form an ohmic contact with the first region of the first substrate 110. In one embodiment, the mechanically rigid conductive deposit 130 is a solid and rigid composite pattern made of a pure metal, a solid metal salt, a metal oxide, or a combination thereof. For example, the mechanically rigid conductive deposit 130 includes platinum Pt, gold Au, silver Ag, or a combination thereof, and / or a combination thereof with carbon. Specifically, since the first substrate 110 is a semiconductor, at the interface between the first substrate 110 and the mechanically rigid conductive deposit 130, the local structure 112 of the first substrate 110 below the mechanically rigid conductive deposit 130 can be transformed into a metallic phase, thereby allowing an ohmic contact to be formed. In various embodiments, the local structure 112 of the first substrate 110 is a phase change layer. It should be noted that the local structure 112 of the phase change layer depicted in the drawings of the present disclosure is illustrative. In practice, its shape or size does not need to be made in proportion to the drawings; for example, the phase change layer 112 can be relatively thin relative to other layers. In addition, in some embodiments, the local structure 112 of the first substrate 110 has various contours; for example, Figure 1D 1 is a vertical cross-sectional view of the profile of a local structure 112' of the first substrate 110' in an embodiment of the present invention, wherein the local structure 112' of the phase change layer is separated from the sidewall / side of the first substrate 110', that is, the present invention does not limit the cross-sectional profile of the local structure 112'.

[0041] This configuration can be achieved by performing the material deposition process at a low conversion temperature using a direct write laser technique, and without using a mask on the first substrate 110 or the second substrate 120. In the present disclosure, as mentioned, "low conversion temperature" means that during the material deposition process, the manufacturing temperature is room temperature or close to room temperature. In some cases, "low temperature" refers to a low test temperature, which allows for truly low temperatures far below zero degrees Celsius, such as as low as 100K or below zero degrees Celsius.

[0042] Specifically, Figure 2A , Figure 2B and Figure 2C A schematic diagram is shown illustrating a method of creating an electrode on a semiconductor by photon-induced deposition of a conductive material to establish an ohmic contact.

[0043] exist Figure 2A In the method, a first solution 150 and a first suspension 152 are prepared. The first solution 150 includes a metal acid salt, a metal ion, or a combination thereof. In one embodiment, the first solution 150 includes gold (III) chloride hydrochloride (HAuCl4), chloroplatinic acid (H2PtCl6), silver nitrate (AgNO3), or a combination thereof. The first suspension 152 includes nanoparticles, a photosensitive reducing agent, an electron donor solvent, or a combination thereof. In one embodiment, the electron donor solvent includes water, ethanol, propanol, isopropanol, acetone, methanol, or a combination thereof. In one embodiment, the photosensitive reducing agent includes reduced graphene oxide, quantum dots, carbon ink particles, or a combination thereof.

[0044] exist Figure 2B In the present invention, this stage starts with transferring the first substrate 110 (e.g., semiconductor) onto the second substrate 120 (e.g., support base / substrate). Then, the first solution 150 and the first suspension 152 are mixed to form the first reagent 154 on the first substrate 110, thereby applying the prepared solution containing metal acid salt or metal ions, reactive reducing ions and low surface tension solvent to the surface of the first substrate 110. In one embodiment, the first reagent 154 can also be applied to the first substrate 110 by drop casting, spin coating, spray coating, microfluidic channel, ink injection or a combination thereof.

[0045] exist Figure 2CIn the embodiment, a light source 160 (eg, a laser light source) provides a light beam 162 (eg, a laser beam) and emits it to the first substrate 110. The light beam 162 is focused onto the first reagent held on the first region R1 of the first substrate 110 (see Figure 2B ), thereby forming a mechanically rigid conductive deposit 130 in contact with the first substrate 110 at the focus of the light source 160, which also causes a phase change locally at the semiconductor surface of the first region R1 of the first substrate 110 (i.e., Figure 1B and Figure 1C In this regard, the first substrate 110 further has a second region R2 adjacent to the first region R1 and exposed to the surrounding gas or air environment. That is, Figure 2C The process in the stage is a maskless process during the formation of the mechanically rigid conductive deposit 130. Since the second region R2 is not irradiated by the light beam 162, the part in the second region R2 is not optically damaged. Accordingly, the phase change can be achieved without changing at least one property of the semiconductor in the second region R2 of the first substrate 110. Figure 2C In the phase, a local structure 112 of the phase change layer is also formed; it should be noted that Figure 2C The size / profile / shape of the local structure 112 of the phase change layer shown in FIG. 1 is illustrative and is not intended to limit the features of the present invention.

[0046] Here, the interactions in the process are briefly introduced: when the laser beam 162 with appropriate power is focused on the semiconductor of the first substrate 110, the photon-induced chemical reduction process is completed, causing the conductive material to aggregate into the mechanically rigid conductive deposit 130. At the same time, a material phase change is triggered below the deposited material, causing a local in-situ transition from a semiconductor state to a metallic state. In the absence of a work function mismatch between the metal and the semiconductor (the mechanically rigid conductive deposit 130 and the first substrate 110), an ohmic contact can be successfully established (i.e., the mechanically rigid conductive deposit 130 can form an ohmic contact with the first region R1 of the first substrate 110 in situ). In one embodiment, the ohmic contact is achieved by the coexistence of an in-situ phase transition of the semiconductor to a metallic state and deposition of a photon conductive material. Therefore, such a process can deposit a solid metal structure with a functional pattern and maintain strong adhesion to the first substrate 110, so that semiconductor and device manufacturing can be directly tested. For example, it can be used Figure 1A The test is directly performed by connecting the test line 140 to the mechanically rigid conductive deposit 130.

[0047] At this stage, although reduction has occurred, the first substrate 110 and the mechanically rigid conductive deposit 130 are still immersed in the first reagent 154. In some embodiments, the first reagent 154 is removed during the cleaning process. In various embodiments, when the droplets of the first reagent 154 are small enough, the mechanically rigid conductive deposit 130 may not be immersed (i.e., at least exposed from the first reagent 154). In one embodiment, the entire structure including the substrate and the combination of the first substrate 110 and the mechanically rigid conductive deposit 130 is completely immersed in the first reagent 154.

[0048] The following provides information about Figure 2C Further details of the reaction process during the stages.

[0049] As described above, when the photon-induced chemical reduction process is completed, the conductive material aggregates into a mechanically rigid deposit; when the light beam 162 is focused on the first reagent, the photons excite free electrons from the valence band of the photosensitive reducing agent (e.g., semiconductor nanoparticles), thereby triggering the chemical reduction process. In this process, the metal ions in the solution are converted into metal particles on the semiconductor surface of the first substrate 110.

[0050] Then, as the initial block of material is formed, local laser heating increases the vapor pressure until vapor microbubbles are formed. At this point, convection and capillary forces carry the particles to the bottom of the microbubbles, where some of the particles are retained. At the same time, the focusing of the first substrate 110 also acts as a light trap, driving the particles to the light focus on the substrate surface of the first substrate 110, while the scattering force strengthens the adhesion between the particles and the first substrate 110. This process can occur together with the photoelectrons generated by the semiconductor of the first substrate 110, which enhances the redox reaction. Through the combination of these mechanisms, the reduced metal or metal oxide grown on the surface of the particles can act like a colloid, bonding the captured particles together to form a mechanically rigid deposit (i.e., a mechanically rigid conductive deposit 130) on the substrate surface of the first substrate 110 or on the already deposited material layer (for 3D patterns).

[0051] At the same time, through the in-situ etching mechanism, a strong adhesion is formed between the deposited material and the first substrate 110. At the same time, through electron transfer or local electric field, a semiconductor phase change occurs in situ. For this, electron transfer is achieved through the combined action of plasma electrons of the deposited metal, hole scavenger solvent in the solution, and photon-excited photoelectrons. In the coexistence of laser, plasma metal and hole scavenger solvent, the local structure of the semiconductor of the first substrate 110 below the deposited metal can be transformed into a metallic phase (i.e. Figure 1B and Figure 1C The local structure 112 in the structure is formed to achieve ohmic contact.

[0052] Then, if Figure 2DAs shown, the next stage is performed to obtain one or more electrodes having a desired shape. In short, by controlling the relative movement of the light source 160 and the target sample (e.g., a reagent applied to the first substrate 110), the continuous deposition of metal can produce one or more electrodes. In addition, the light source 160 can be extended to the semiconductor-free area of ​​the first substrate 110 to facilitate measurement. In one embodiment, the laser writing process is repeated and the sample is thoroughly cleaned to complete the FET configuration. Figure 2D In the phase, a local structure 112 of the phase change layer is also formed; it should be noted that Figure 2D The size / profile / shape of the local structure 112 of the phase change layer shown in FIG. 1 is illustrative and is not intended to limit the present invention.

[0053] For example, movement of the light source may cause its focus to move as well, resulting in a mechanically rigid conductive deposition 130 being formed as a conductive pattern on the first substrate 110, wherein the distribution area of ​​the conductive pattern depends on the moving region of the focus of the light source 120 (for example, extending from the region irradiated by the light beam 162A to the region irradiated by the light beam 162B).

[0054] For example, the light source moves from the first substrate 110 to the second substrate 120 along a moving path (e.g., a path from light beam 162A to light beam 162C), so that its focus also moves along the same path, thereby forming a mechanically rigid conductive deposit 130 along the moving path, so that the conductive pattern of the mechanically rigid conductive deposit 130 extends from the first substrate 110 to the second substrate 120.

[0055] In one embodiment, after the deposit is formed, the above method can be repeated to obtain a thicker or denser deposit (e.g., a mechanically rigid conductive deposit 130); or different material depositions can be obtained by changing the first solution 150 containing metal salts or metal ions or the first suspension 152 containing nanoparticles or photosensitive reducing agents and repeating the above method.

[0056] In various embodiments, light source 160 is a laser, particularly a continuous wave laser or a pulsed laser, preferably in the visible light range, and preferably has a wavelength of 532nm. In various embodiments, light source 160 can be focused by a lens, preferably using an air objective lens, an oil objective lens or a water immersion objective lens. In various embodiments, the light from light source 160 can be guided to the reagent by free space, and / or by at least one photon waveguide, and / or by at least one optical fiber, and / or by attenuation coupling. In the process as described above, the power of the light or laser is maintained at a low level, for example, for any substrate, it can be maintained at a maximum of 400mW. The power depends on the numerical aperture value of the applied objective lens. In contrast, common laser writing methods require high-power ultrafast lasers.

[0057] Figure 3A , Figure 3B , Figure 3C and Figure 3D Raman spectra of different noble metals deposited on different TMDs according to some embodiments of the present invention are shown. These Raman spectra are direct evidence of the existence of in-situ phase transitions in TMDs. Figure 3A It is made for platinum (Pt) on molybdenum disulfide (MoS2). Figure 3B It was made for gold (Au) on molybdenum disulfide (MoS2); it shows that the lattice of molybdenum disulfide (MoS2) below the deposited material has transformed into a metallic phase, while other areas of the MoS2 still remain in the semiconductor phase as channels. Figure 3C It is made for platinum (Pt) on tungsten diselenide (WSe2). Figure 3D This was done for gold (Au) on tungsten (WSe2); it also shows the same metallic phase change in the deposited area, while the rest of the channel area remains unchanged.

[0058] In order to verify the ohmic contact on the MS interface, the electrical characteristics of the Pt-MoS2 devices were tested at different temperatures. Figure 4A , Figure 4B , Figure 4C , Figure 4D The electrical measurement diagrams of FET devices manufactured using the technical solutions according to some embodiments of the present invention are provided together. The samples used for FET devices are samples based on molybdenum disulfide (MoS2) with platinum (Pt) electrodes, which contain multiple channels on the same TMD.

[0059] like Figure 4A and Figure 4B As shown in the figure, drain-source bias voltage (Vds) is applied to different pairs of platinum electrodes on the same sample to measure the total resistance of metal-semiconductor (MS) contact and channel transmission. The total resistance refers to the sum of channel resistance and contact resistance. Figure 4A The linear relationship between the current measured between the source and drain and the applied voltage provides direct evidence of an ohmic contact. The total resistance measured at room temperature is approximately 2 MΩ. Figure 4B In the figure, the temperature dependence of the total resistance of different channels on the same sample is shown, which shows a negative exponential dependence, which is consistent with the electrical properties of the channel material. Figure 4A The ohmic contact of the metal-semiconductor interface is directly demonstrated because the applied drain-source bias voltage and the measured drain-source current have a linear relationship; Figure 4B It was shown that as the temperature decreases, the total resistance also decreases, which is the same characteristic property of semiconductors, thus indirectly proving the ohmic contact.

[0060] In addition, a MoS2 field effect transistor with a size class of 15 microns was fabricated, which fully demonstrated the potential of the present invention and the possibility of further applications. The output current of the field effect transistor at the same drain-source voltage (Vds) was measured at different back gate voltages, and good current saturation was observed. Figure 4C The transfer characteristics of the field effect transistor device at different temperatures are shown, and it can be observed that it exhibits N-type channel behavior. In addition, Figure 4D The mobility of the field effect transistor device is shown, which is a reasonable and usable level. Based on this, it is estimated that the mobility of the field effect transistor device is about 8.5 cm 2 V -1 s -1 , which is already at a level that can be used in practice.

[0061] In addition, by means of the solution provided by the present invention, a solid metal structure with strong adhesion can be deposited in different solvents, including acetone, isopropanol or ethanol, which remains intact after more than 30 minutes of ultrasonic treatment. In one embodiment, the solution provided by the present invention can be combined with the optical characterization of semiconductor samples, thereby allowing sample selection, device manufacturing and optical quality inspection within the same device. In one embodiment, the solution provided by the present invention can be used to manufacture electronic products, to manufacture flexible devices and / or quantum devices, and / or photonic structures, and / or electrodes for testing the electronic properties of two-dimensional materials, in particular in a manner that prints circuits using a printer.

[0062] Based on the above content, various embodiments of the present invention also provide more structural configurations.

[0063] Figure 5 1 is a vertical cross-sectional view of a semiconductor device 100B according to some embodiments of the present invention. The configuration of the semiconductor device 100B is similar to that of the semiconductor device 100A, except that the semiconductor device 100B further includes electrodes having different thicknesses formed by mechanically rigid conductive depositions 130A and 130B. The mechanically rigid conductive depositions 130A and 130B are formed in different regions (e.g., the first region R1 and the second region R2) of the first substrate 110 and have different thicknesses. The mechanically rigid conductive depositions 130A and 130B may have the same composition.

[0064] During the process, the solution and the suspension are mixed on the first substrate 110 to form a reagent again; then, the light beam is focused on the reagent held on a partial area within the first substrate 110 (which is different from the first area R1) to form an additional conductive deposit 130B in contact with the first substrate 110. Moreover, the mechanically rigid conductive deposit 130B can be formed by repeated multiple times. Figure 2A , Figure 2B and Figure 2C The mechanically rigid conductive deposit 130A is formed by the steps shown in the stages (ie, it is formed more times than the mechanically rigid conductive deposit 130A).

[0065] Figure 6 is a vertical cross-sectional view of a semiconductor device 100C according to some embodiments of the present invention. The configuration of the semiconductor device 100C is similar to that of the semiconductor device 100B, except that the semiconductor device 100C includes electrodes with different thicknesses formed by mechanically rigid conductive deposits 130A, 130B in contact with each other. The mechanically rigid conductive deposits 130A, 130B in contact with each other can provide a modulation effect on the resistance of the electrodes.

[0066] Figure 7 1 is a vertical cross-sectional view of a semiconductor device 100D according to some embodiments of the present invention. The configuration of the semiconductor device 100D is similar to that of the semiconductor device 100A, except that the semiconductor device 100D further includes electrodes formed by mechanically rigid conductive deposits 130C, 130D having different compositions. In one embodiment, the mechanically rigid conductive deposit 130C and the mechanically rigid conductive deposit 130D have different metal elements. For example, the mechanically rigid conductive deposit 130D has a metal element that is not present in the mechanically rigid conductive deposit 130C.

[0067] The mechanically rigid conductive deposit 130C can be formed by the method described above. During its formation, a second solution is first prepared and mixed with the suspension to form a second reagent on the first substrate 110. The second reagent contains Figure 2B The light beam is then focused onto the second reagent held on an area different from the first region R1 within the first substrate 110, thereby forming an additional conductive deposit 130D in contact with the first substrate 110. Therefore, the electrodes of the mechanically rigid conductive deposits 130C, 130D can have different characteristics, thereby providing a regulating effect on their resistance.

[0068] Figure 8 is a vertical cross-sectional view of a semiconductor device 100E according to some embodiments of the present disclosure. The configuration of the semiconductor device 100E is similar to that of the semiconductor device 100D, except that the semiconductor device 100E includes electrodes formed by mechanically rigid conductive deposits 130C, 130D contacting each other.

[0069] Fig. 91 is a vertical cross-sectional view of a semiconductor device 100F according to some embodiments of the present invention. The configuration of the semiconductor device 100F is similar to the configuration of the semiconductor device 100A, except that the semiconductor device 100F further includes an electrode formed by a mechanically rigid conductive deposit 130F, which is disposed above the mechanically rigid conductive deposit 130E. Specifically, the mechanically rigid conductive deposit 130F has a different composition than the mechanically rigid conductive deposit 130E and is formed to contact the top surface of the mechanically rigid conductive deposit 130E. In one embodiment, the mechanically rigid conductive deposit 130E and the mechanically rigid conductive deposit 130F have different thicknesses. For example, the mechanically rigid conductive deposit 130F is thicker than the mechanically rigid conductive deposit 130E. In one embodiment, the formation of the mechanically rigid conductive deposit 130F can be controlled so that the mechanically rigid conductive deposit 130E and the mechanically rigid conductive deposit 130F have the same width.

[0070] The mechanically rigid conductive deposit 130E can be formed by the above method. During its formation, a second solution is first prepared and mixed with the suspension to form a second reagent (for example, the second reagent includes an element or compound not present in the first reagent) on the mechanically rigid conductive deposit 130E; thereafter, the light beam is focused on the second reagent held on the mechanically rigid conductive deposit 130E, and an additional conductive deposit 130F in contact with the mechanically rigid conductive deposit 130E can be formed. Therefore, the electrodes of the mechanically rigid conductive deposits 130E and 130F can provide the desired adjustment effect on their resistance.

[0071] Fig.10 is a vertical cross-sectional view of a semiconductor device 100G according to some embodiments of the present invention. The configuration of the semiconductor device 100G is similar to that of the semiconductor device 100F, except that the semiconductor device 100G includes electrodes formed of mechanically rigid conductive deposits 130C, 130D having the same thickness.

[0072] Fig.11 is a vertical cross-sectional view of a semiconductor device 100H according to some embodiments of the present invention. The configuration of semiconductor device 100H is similar to that of semiconductor device 100A, except that semiconductor device 100F further includes an electrode formed of a mechanically rigid conductive deposition 130G having an inverted trapezoidal shape. Fig.121 is a vertical cross-sectional view of a semiconductor device 100I according to some embodiments of the present invention. The configuration of the semiconductor device 100I is similar to that of the semiconductor device 100A, except that the semiconductor device 100I further includes an electrode formed by a mechanically rigid conductive deposit 130H having a curved surface. For mechanically rigid conductive deposits of different shapes, the movement trajectory of the laser source is controlled when the conductive pattern thereof is formed by a laser beam, and different desired shapes can be generated. In other words, the movement trajectory of the laser beam can determine the profile of the electrode.

[0073] Fig.13 is a vertical cross-sectional view of a semiconductor device 100J according to some embodiments of the present invention; Fig.14 1 is a vertical cross-sectional view of a semiconductor device 100K according to some embodiments of the present invention. The configurations of the semiconductor devices 100I and 100K are similar to the aforementioned configurations, except that the local structure 112 of the phase change layer in the first substrate 110 is smaller than the mechanically rigid conductive deposition 130 (e.g., narrower than the mechanically rigid conductive deposition 130), which means that only a portion of the first substrate 110 located below the mechanically rigid conductive deposition 130 transitions to become the local structure 112 shown (i.e., at least a portion of the first substrate 110 located below the mechanically rigid conductive deposition 130 remains in an intrinsic state).

[0074] As described above, the present invention realizes the deposition of conductive materials on the semiconductor surface with ohmic contact through in-situ phase change, and its advantages are as follows: (1) Local phase change can be achieved without changing the semiconductor material of the channel part. (2) This method allows electrical measurements to be made directly on semiconductors. (3) The contact resistance of the MS surface is quite small. (4) This method can use precious metals as electrodes to reduce electrode resistance. (5) This method can be deployed in a simple environment at room temperature and does not require extreme conditions. (6) This method requires low energy and solution costs. (7) This method is readily available and test samples can be produced within minutes. (8) This approach allows the integration of sample selection, electrode deposition, and optical inspection processes into a single setup. (9) This method allows for surface phase transitions that do not alter the structure of the semiconductor beneath the surface. (10) This method can achieve ohmic contact without damaging the semiconductor sample.

[0075] The foregoing description of the present invention is for the purpose of illustration and description. It is not intended to be exhaustive or to limit the present invention to the precise form disclosed. Many modifications and variations will be apparent to those skilled in the art.

[0076] The embodiments were chosen and described in order to best explain the principles of the invention and its practical applications, thereby enabling others skilled in the art to understand the invention for various embodiments and with various modifications as are suited to the particular use contemplated.

Claims

1. A method for photon-induced deposition of a conductive material on a substrate, characterized in that: include: preparing a first solution comprising a metal acid salt, a metal ion, or a combination thereof; preparing a first suspension comprising nanoparticles, a photosensitive reducing agent, an electron donor solvent, or a combination thereof; mixing the first solution and the first suspension to form a first reagent on a first substrate; as well as A light beam provided by a light source is emitted and focused onto the first reagent held on a first area of ​​the first substrate, thereby forming a mechanically rigid conductive deposit in contact with the first substrate at the focus of the light source, wherein the first substrate has a second area exposed to an ambient gas or air environment.

2. The method according to claim 1, characterized in that The first substrate includes molybdenum disulfide (MoS2), molybdenum diselenide (MoSe2), molybdenum ditelluride (MoTe2), tungsten diselenide (WSe2), graphene, a layer with a metal isomer, or a combination thereof, thereby serving as a two-dimensional material to form at least one channel within the first substrate.

3. The method according to claim 2, characterized in that The mechanically rigid conductive deposit forms an in-situ ohmic contact with the first region of the first substrate.

4. The method according to claim 1, characterized in that: Also includes: The focus of the light source is moved to make the mechanically rigid conductive deposit form a conductive pattern on the first substrate, wherein a distribution area of ​​the conductive pattern depends on a moving area of ​​the focus of the light source.

5. The method according to claim 4, characterized in that The first substrate is located above and attached to a second substrate, and the method further comprises: The focus of the light source is moved from the first substrate to the second substrate along a movement path to form the mechanically rigid conductive deposit along the movement path such that the conductive pattern of the mechanically rigid conductive deposit extends from the first substrate to the second substrate.

6. The method according to claim 5, characterized in that The second substrate includes glass, quartz, sapphire, indium tin oxide, diamond, silicon, silicon carbide (SiC), silicon oxide, or a combination thereof.

7. The method according to claim 1, characterized in that The first solution includes gold (III) chloride hydrochloride (HAuCl4), chloroplatinic acid (H2PtCl6), silver nitrate (AgNO3), or a combination thereof.

8. The method according to claim 1, characterized in that: The electron donor solvent includes water, ethanol, propanol, isopropanol, acetone, methanol or a combination thereof.

9. The method according to claim 1, characterized in that: The photosensitive reducing agent includes reduced graphene oxide, quantum dots, carbon ink particles or a combination thereof.

10. The method according to claim 1, characterized in that The first substrate is a semiconductor, and forming the mechanically rigid conductive deposition causes a local phase change at a surface of the semiconductor in the first region of the first substrate without changing at least one property of the semiconductor in the second region of the first substrate.

11. The method according to claim 1, characterized in that: The mechanically rigid conductive deposit is a solid and rigid composite pattern made of pure metal, solid metal salt, metal oxide or a combination thereof.

12. The method according to claim 1, characterized in that Also includes: After forming the mechanically rigid conductive deposit, mixing the first solution and the first suspension to form the second reagent on the first substrate; as well as The light beam provided by the light source is focused onto the second reagent held on the third area of ​​the first substrate to form an additional conductive deposit in contact with the third area of ​​the first substrate.

13. The method according to claim 1, characterized in that Also includes: mixing the first solution and the first suspension to form a second reagent on the mechanically rigid conductive deposit; as well as The light beam provided by the light source is focused onto the second reagent held on the mechanically rigid conductive deposit to form an additional conductive deposit in contact with the mechanically rigid conductive deposit.

14. The method according to claim 1, characterized in that Also includes: After forming the mechanically rigid conductive deposit, forming a second reagent on the first substrate, wherein the second reagent includes an element or compound not present in the first reagent; as well as The light beam provided by the light source is focused onto the second reagent held on the third area of ​​the first substrate, thereby forming an additional conductive deposit in contact with the third area of ​​the first substrate.

15. A semiconductor device using photon-induced deposition of conductive material, characterized in that include: A first substrate having a first region and a second region adjacent to the first region, wherein the first substrate comprises molybdenum disulfide (MoS2), molybdenum diselenide (MoSe2), molybdenum ditelluride (MoTe2), tungsten diselenide (WSe2), graphene, a layer having a metal isomer, or a combination thereof, and is used as a two-dimensional material to form at least one channel in the first substrate; a mechanically rigid conductive deposit formed into a conductive pattern and disposed over the first region of the first substrate, wherein the mechanically rigid conductive deposit forms an ohmic contact with the first region of the first substrate, and the mechanically rigid conductive deposit is a solid and rigid composite pattern made of pure metal, solid metal salt, metal oxide, or a combination thereof; as well as A second substrate is attached to the first substrate, wherein the mechanically rigid conductive deposit is located over the first substrate and the second substrate and extends from the first region of the first substrate to the second substrate.

16. The semiconductor device according to claim 15, characterized in that The second substrate includes glass, quartz, sapphire, indium tin oxide, diamond, silicon, silicon carbide (SiC), silicon oxide, or a combination thereof.

17. The semiconductor device according to claim 16, characterized in that Also includes: An additional conductive deposit, formed as a conductive pattern, is located over the second region of the first substrate, wherein the additional conductive deposit forms an ohmic contact with the second region of the first substrate and is a solid and rigid composite pattern made of pure metal, solid metal salt, metal oxide, or a combination thereof.

18. The semiconductor device according to claim 17, wherein: The mechanically rigid conductive deposit and the additional conductive deposit have different metallic elements.

19. The semiconductor device according to claim 17, wherein: The mechanically rigid conductive deposit and the additional conductive deposit have different thicknesses.

20. The semiconductor device according to claim 17, wherein: The additional conductive deposit has a metallic element that is not present in the mechanically rigid conductive deposit.

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