KR102602680B1 - Structures and devices including germanium-tin films and methods of forming same - Google Patents

Abstract

Methods for forming germanium-tin films using germanium as a precursor are disclosed. Exemplary methods include growing films comprising germanium and tin in an epitaxial chemical vapor deposition reactor, wherein the ratio of tin precursor to germanium is less than 0.1. Structures and devices comprising germanium-tin films formed using the methods described herein are also disclosed.

Description

Structures and devices including germanium-tin films and methods of forming same}

[1] This application is a continuation-in part of U.S. Patent Application No. 13/966,782, filed on August 14, 2013 under the title “Methods of Forming Films Including Germanium Tin and Structures and Devices Including the Films” am. The disclosure thereof is incorporated herein by reference.

[2] This disclosure generally relates to techniques for depositing films containing germanium and tin and structures and devices containing such films. More specifically, the present disclosure includes methods of forming films containing germanium and tin using germane as a precursor, methods of forming structures and devices comprising the films, and the films. It relates to structures and elements that do.

[3] Various electronic devices, such as semiconductor devices, and optical devices, such as lasers and solar devices, may or may preferably include germanium-tin layers such as GeSn, GeSiSn, etc. For example, GeSn layers can be used to form direct band gap devices and/or to provide strain to an adjacent germanium layer to increase mobility within the germanium layer. can be used Similarly, GeSiSn layers can be used to form tunable band gap devices as well as optical devices with tunable optical properties. To obtain the desired device properties, the germanium-tin films generally have a crystalline structure, which generally follows the crystalline structure of the underlying layer.

[4] GeSn layers can be deposited or grown using a variety of techniques. For example, vacuum processes including molecular beam epitaxy and ultra-high vacuum chemical vapor deposition have been used to form GeSn films. Germanium precursors for these processes typically include digermane (Ge ₂ H ₆ ) or trigermane (Ge ₃ H ₈ ). If the film comprises silicon, the silicon precursor may be disilane, trisilane, or other higher order silane compounds, or (H ₃ Ge) _x SiH _{4 -x} (x =1~4), (H ₃ Si) _x GeH _{4 -x} (x=1~4).

[5] Although these processes have been used to deposit or grow crystalline GeSn and GeSiSn layers, the use of degermaine, trigermaine, or higher order germane precursors can be problematic in several ways. For example, the formation of films or layers comprising GeSn using higher order germane precursors such as degermaine or trigermaine can be achieved by combining certain carrier gases (e.g. hydrogen) and/or dopants (e.g. p type dopants) are not selective when used with the precursor. Additionally, degermaine is relatively unstable (explosive) in concentrated form; As a result, the amount of the precursor entering a vessel can be generally limited to less than 154 grams, which in turn results in relatively low throughput of processes using this precursor. Additionally, degermains and higher order germanes are relatively expensive. Accordingly, improved processes for forming crystalline films containing GeSn are needed.

The object of the present invention is to overcome the problems described above.

[6] Various embodiments of the present disclosure relate to GeSn films and methods of forming structures and devices including the films. Films formed using the methods described herein can be used in, for example, semiconductor, direct band gap, optical, or any other device containing such films. The ways in which various embodiments of the present disclosure address the shortcomings of prior art methods are described in greater detail below, but generally, the present disclosure utilizes a germane (GeH ₄ ) precursor on the surface of a substrate to produce (e.g., crystalline) germane. Methods of forming nium-tin layers and structures and devices comprising such films are provided.

[7] As used herein, germanium-tin (GeSn) layers (also referred to herein as films) or layers containing germanium and tin are layers that contain the elements germanium and tin. The layers may contain additional elements, for example silicon (eg GeSnSi) or carbon (eg GeSnSiC), or dopants such as boron, gallium, phosphorus, arsenic, or antimony.

[8] According to various embodiments of the present disclosure, methods of forming a layer containing GeSn include providing a gas phase reactor, providing a germane precursor source connected to the gas phase reactor, and a tin precursor connected to the gas phase reactor. providing a source, providing a substrate within a reaction chamber of the gas phase reactor, providing a germanium precursor and a tin precursor to the reaction chamber, and forming a crystalline germanium tin layer on the surface of the substrate (e.g. For example, it includes an epitaxial growth step. According to various aspects of these embodiments, providing a germane precursor and a tin precursor to the reaction chamber may provide a tin to germane precursor of about 0.001 to about 0.1, about 0.005 to about 0.05, less than about 0.1, or less than about 0.05. and providing a mixture of the tin precursor and the germaine precursor having a precursor volume ratio. The reaction chamber temperature and pressure during the steps of forming the germanium tin crystalline layer can vary depending on various factors. Exemplary reaction chamber temperatures range from about 200°C to about 500°C, from about 250°C to about 450°C, or from about 300°C to about 420°C. Exemplary reaction chamber pressures during this step range from about 300 Torr to about 850 Torr, about 400 Torr to about 800 Torr, about 500 Torr to about 760 Torr, ambient atmospheric pressure ± about 20 Torr, ambient atmospheric pressure ± about 10 Torr, or ambient atmospheric pressure ± about 5 Torr. . According to further aspects of these embodiments, the germanium-tin layer includes silicon. In this case, the method further includes providing a silicon source precursor to the reaction chamber. Exemplary silicon source precursors include disilane, trisilane, tetrasilane, neopentasilane, and higher order silane compounds. The amount of tin included in the crystalline germanium-tin layer is greater than 1 at% (atomic percent), greater than 2 at%, or greater than 5 at%, or about 0 at% to about 15 at% tin, or about 2 at% to about 15 at% tin, about It may be from 0.2 at% to about 5 at% tin, or from about 0.2 at% to about 15 at% tin. When the crystalline germanium-tin layer comprises silicon, the layer has greater than 0 at% silicon, greater than about 1 at% silicon, or about 1 at% silicon to about 20 at% silicon, about 2 at% silicon to about 16 at% silicon, or about It may contain from 4 at% silicon to about 12 at% silicon. According to further aspects of these embodiments, the substrate includes silicon. According to other aspects, the substrate includes a germanium layer (eg overlying silicon). Exemplary methods according to these embodiments include forming an insulating layer overlying the substrate, forming a via in the insulating layer, and forming a via in the via to overly overly the substrate. Additionally comprising (e.g. optionally) forming a nium-tin layer, wherein the substrate may include one or more previously formed layers.

[9] According to further exemplary embodiments of the present disclosure, a method of forming a structure comprising a germanium-tin layer (e.g., crystalline) includes providing a gas phase reactor, within a reaction chamber of the gas phase reactor. Providing a substrate, and forming a layer comprising germanium and tin (eg, crystalline) on the surface of the substrate using one or more precursors comprising germanium (GeH ₄ ). According to various aspects of these embodiments, forming a layer comprising germanium and tin comprises a tin precursor to germanium of about 0.001 to about 0.1, about 0.005 to about 0.05, less than about 0.1, or less than about 0.05. and providing a mixture of the tin precursor and the germane having a volume ratio of . According to further aspects, the reaction chamber temperature during the step of forming the germanium tin crystalline layer ranges from about 200°C to about 500°C, from about 250°C to about 450°C, or from about 300°C to about 420°C. According to still further aspects, the reaction chamber pressure during the step of forming the layer comprising germanium tin is from about 300 Torr to about 850 Torr, about 400 Torr to about 800 Torr, about 500 Torr to about 760 Torr, ambient atmospheric pressure ± about 20 Torr, It is in the range of ambient atmospheric pressure ± about 10 Torr, or ambient atmospheric pressure ± about 5 Torr. According to still further aspects of these embodiments, forming a layer comprising germanium and tin includes forming a layer comprising silicon germanium tin. In this case, a silicon precursor is provided to the reaction chamber. Exemplary silicon source precursors include disilane, trisilane, tetrasilane, neopentasilane, and higher order silane compounds. The amount of tin included in the germanium-tin layer is greater than 1 at%, greater than 2 at%, or greater than 5 at%, or about 0 at% to about 15 at% tin, about 2 at% to about 15 at% tin, about 0.2 at% to about 0.2 at% tin. It may be 5 at% tin, or about 0.2 at% to about 15 at% tin. When the crystalline germanium-tin layer comprises silicon, the layer has greater than 0 at% silicon, greater than about 1 at% silicon, or about 1 at% silicon to about 20 at% silicon, about 2 at% silicon to about 16 at% silicon, or about It may contain from 4 at% silicon to about 12 at% silicon. According to various aspects of these embodiments, the substrate includes silicon. According to other aspects, the substrate includes a germanium layer (eg overlying silicon). Exemplary methods according to these embodiments include forming an insulating layer overlying the substrate, forming a via in the insulating layer, and forming the germanium-tin layer (e.g., within the via) overlying the substrate. For example, it additionally includes a forming step (optionally).

[10] According to still further embodiments of the present disclosure, the structure includes a crystalline germanium-tin layer formed according to the method of the present disclosure. The structure can be used to form electronic (eg semiconductor) or optical (eg solar or light emitting) devices.

[11] And according to still further exemplary embodiments of the present disclosure, the device includes a crystalline germanium-tin layer formed according to the method of the present disclosure.

[12] A more complete understanding of exemplary embodiments of the present disclosure can be derived from the specification and claims for carrying out the invention when considered in conjunction with the following illustrative drawings.
[13] Figure 1 shows a system for forming a crystalline germanium tin layer according to example embodiments of the present disclosure.
[14] Figure 2 shows a method of forming a layer comprising germanium tin according to further example embodiments of the present disclosure.
[15] Figure 3 shows another method of forming a layer containing germanium tin according to example embodiments of the present disclosure.
[16] Figure 4 shows a structure according to example embodiments of the present disclosure.
[17] Figure 5 shows a rocking scan of a structure according to example embodiments of the present disclosure.
[18] Figure 6 shows another structure according to still further exemplary embodiments of the present disclosure.
[19] Figure 7 shows another structure according to further example embodiments of the present disclosure.
[20] It will be understood that elements in the drawings are drawn for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the components in the drawings may be exaggerated relative to other components to help improve the understanding of the illustrated embodiments of the present disclosure.

[21] The description of example embodiments of methods, structures, and devices provided below is illustrative only and is intended for illustrative purposes only; The following description is not intended to limit the scope of the disclosure or the claims. Moreover, the description of multiple embodiments having recited features is not intended to exclude other embodiments having additional features or including different combinations of the recited features.

[22] The present disclosure generally relates to methods of forming layers, such as a crystalline layer comprising germanium and tin, placed on a substrate. The germanium-tin layers may include additional elements such as silicon and/or carbon that together with the germanium-tin layer form part of the crystal lattice.

[23] As used herein, “substrate” refers to any material having a surface on which material can be deposited. The substrate may include a bulk material such as silicon (eg, single crystal silicon, single crystal germanium, or another semiconductor wafer) or may include one or more layers overlying the bulk material. Additionally, the substrate may have various topologies such as trenches, vias, lines, etc. formed in or on at least a portion of a layer of the substrate. Exemplary substrates include a silicon wafer, a layer comprising germanium on silicon, and a layer comprising germanium silicon tin on silicon.

[24] Figure 1 shows a system 100 suitable for forming germanium-tin using the methods described herein. In the example shown, system 100 includes a reactor 102, a germaine precursor source 104, a tin precursor source 106, and an optional third precursor source 108 (e.g., silicon or other elements within the formed layer). (s), a purge and/or carrier gas source 110, an optional mixer 112, an optional intake plenum 114, and a vacuum source 116. Includes. Sources 104-110 may be connected to mixer 112 or reactor 102 using lines 118-132 and valves 134-140. Although not shown, a system such as system 100 includes additional sources for dopants (e.g. n-type dopants such as phosphorus or arsenic or p-type dopants such as boron) and corresponding transport lines. can do. Additionally or alternatively, the dopants may be included in one or more of the precursor sources 102-108.

[25] Reactor 102 may be a stand-alone reactor or part of a cluster tool. Additionally, reactor 102 may be dedicated to specific processes, such as deposition processes, or reactor 102 may be used for other processes, such as layer passivation and/or etch processes. For example, reactor 102 may be an Epsilon ^® 2000Plus or Intrepid ^TM available from ASM. It may include reactors commonly used in epitaxial chemical vapor deposition (expitaxial CVD) processes, such as XP, and may include direct plasma, and/or remote plasma devices (not shown) and/or radiation, It may include various heating systems, such as induction, and/or resistance heating systems (not shown). Using plasma can increase the reactivity of one or more precursors. The reactor shown is a single substrate, horizontal flow reactor that allows laminar flow of reactants over the substrate 142 and has a low residence time that allows for relatively fast continuous substrate processing. Examples suitable for system 100 include U.S. Pat. No. 7,476,627, issued Jan. 13, 2009 to Pomarede et al., the contents of which are incorporated herein by reference to the extent that their contents do not conflict with this disclosure. A typical CVD reactor is described. Although shown as a horizontal-flow reactor, reactor 102 according to alternative embodiments may include a vertical flow, for example, a flow exiting a showerhead and flowing substantially downwardly over the substrate.

[26] The operating pressure of the reaction chamber 144 of the reactor 102 may vary depending on various factors. Reactor 102 may be configured to operate near ambient atmospheric pressure. Operating near ambient atmospheric pressure allows for relatively rapid film formation. For example, the operating pressure of reactor 102 during layer formation steps may be about 300 Torr to about 850 Torr, about 400 Torr to about 800 Torr, about 500 Torr to about 760 Torr, ambient atmospheric pressure ± about 20 Torr, ambient atmospheric pressure ± about 10 Torr, or Ambient atmospheric pressure ± approximately 5 Torr range.

[27] The source 104 includes germane (GeH ₄ ) and may optionally include one or more dopant compounds, such as compounds commonly used to manufacture optical and/or semiconductor devices. Exemplary p-type dopant compounds include B ₂ H ₆ and exemplary n-type dopant compounds include AsH ₃ .

[28] Germaine is relatively selective when mixed with various carrier gases (e.g. hydrogen, nitrogen, etc.), even when dopants (e.g. p-type dopants) are used with the precursor (e.g. For example, as it can be relatively selective (using the various process conditions presented herein), the use of germanium can be compared to other germanium-tin layers used to form germanium-tin layers, such as degermaine, trigermaine, and other higher order germanes. It has advantages over precursors. Additionally, germanes are relatively safe compared to higher order germanes and therefore can be used and/or transported in larger quantities compared to higher order germines. Germaine is also used as a precursor for other layers, such as germanium, and is more readily available and less expensive than higher order germane compounds.

[29] Tin precursor source 106 comprises any compound suitable for supplying tin to the germanium-tin layer. Exemplary tin precursors include tin chloride (SnCl ₄ ), tin deuterium (SnD ₄ ), and _Sn (CH ₃ ) _{4 - n} , 1, 2, or 3); _ZSn (CH ₃ ) _{3 - n} Z ₂ Sn(CH ₃ ) _{2- n} or methyl and/or halide substituted tin compounds, such as compounds having the chemical formula SnBr ₄ . In application No. 13/783,762, filed March 4, 2013, entitled “TIN PRECURSORS FOR VAPOR DEPOSITION AND DEPOSITION PROCESSES,” the contents of which are hereby incorporated by reference to the extent they do not conflict with this disclosure. Some exemplary tin precursors suitable for use with the present disclosure are discussed in more detail.

[30] The optional third precursor source 108, if used, contains precursors for additional elements or compounds that may be included in the deposited layer. For example, precursor source 108 may be a silicon precursor such as disilane, trisilane, tetrasilane, neopentasilane, and higher order silanes, H ₃ SiCH ₃ , (H ₃ Si) ₄ C, CH ₄ , H ₃ GeCH ₃ , and (H ₃ Ge) ₂ CH ₂ and/or one or more compounds suitable as dopant precursors/compounds. If source 108 includes a silicon precursor, as noted above, system 100 may include additional dopant sources and corresponding supply lines.

[31] Gas source 110 may include any suitable purge or carrier gas. Exemplary gases suitable as carrier and purge gases include nitrogen, argon, helium, and hydrogen.

[32] System 100 may include a gas distribution system. To the extent that it does not conflict with this disclosure, U.S. Patent No. No. 8,152,922 presents an exemplary gas distribution system that allows fast switching between gases (e.g., from sources 104-110). The gas distribution system may, for example, distribute one or more precursor gases and a carrier gas (which may be the same or different from the purge gas from gas source 108) to plenum 114 or reactor 102. Can be used to mix before reaching.

[33] Referring now to Figure 2, an exemplary method 200 of forming a crystalline germanium-tin layer is shown. Method 200 includes providing a vapor phase reactor (step 202), providing a germane source coupled to the vapor phase reactor (step 204), providing a tin precursor source coupled to the vapor phase reactor (step 206), providing a substrate in a reaction chamber of a gas phase reactor (step 208), providing germane and tin precursors to the reaction chamber, wherein the ratio of the tin precursor to germane is less than 0.1 (step 210), and It may comprise, consist of, or consist essentially of forming a crystalline germanium tin layer on the surface (step 212). Method 200 may be used to form (e.g., selectively grow) germanium tin films without an etchant during and/or prior to step 212 of forming a germanium tin crystalline layer on the surface of the substrate. there is.

[34] During step 202, a gas phase reactor, such as a CVD reactor suitable for epitaxial growth, is provided. The reactor may be a single-substrate, laminar flow reactor. These reactors are available from ASM such as Epsilon ^® 2000Plus and Intrepid ^TM XP.

[35] During steps 204 and 206, appropriate germane (GeH ₄ ) and tin precursor sources are connected to the reactor. As mentioned above, the germane source may include dopant compounds such as p-type dopant compounds. Alternatively, dopants may be supplied from additional sources (not shown). The tin precursor source may include, for example, tin chloride and/or tin deuterate and/or other tin precursors mentioned herein.

[36] During step 208, a substrate is loaded into the reaction chamber of the reactor. The substrate can be received from the loading load lock of the reactor system and transported to the reaction chamber using an appropriate transport mechanism.

[37] In step 210, the tin precursor and germane are provided to the reaction chamber of the reactor. The tin precursor and germane may be mixed (e.g., in mixer 112) before entering the chamber. Additionally, the germane and tin precursors may be mixed individually or in combination with one or more carrier gases. The germane and/or tin precursor may be mixed with a carrier gas upstream of the reaction chamber, such as in a mixer, or upstream of a mixer.

[38] As mentioned above, the use of germanium has several advantages over the use of conventional precursors used to form layers containing germanium and tin. Surprisingly and unexpectedly, it was found that using relatively high partial pressures of germanium compared to the tin precursor results in the formation of high-quality crystalline germanium tin layers. According to various aspects of exemplary embodiments of the present disclosure, the step of providing germane and tin precursors to the reaction chamber includes a germane concentration of about 0.001 to about 0.1, about 0.005 to about 0.05, less than about 0.1, or less than about 0.05. and providing a mixture of tin precursor and germane having a volume ratio of tin precursor to .

[39] During step 212, a crystalline layer (e.g., an epitaxial layer) is formed overlying the substrate. Exemplary reaction chamber temperatures during step 212 may range from about 200°C to about 500°C, from about 250°C to about 450°C, or from about 300°C to about 420°C. And, exemplary reaction chamber pressures during this step are about 300 Torr to about 850 Torr, about 400 Torr to about 800 Torr, about 500 Torr to about 760 Torr, ambient atmospheric pressure ± about 20 Torr, ambient atmospheric pressure ± about 10 Torr, or ambient atmospheric pressure ± about 5 Torr. It may be a range. Operating at relatively high pressures enables fast throughput of structures containing the germanium tin films.

[40] Step 212 may include forming a layer containing germanium silicon tin. In this case, a silicon precursor is provided to the reaction chamber. Exemplary silicon source precursors include disilane, trisilane, tetrasilane, neopentasilane, and higher order silane compounds. Additionally or alternatively, step 212 includes forming a layer comprising carbon. In this case, the carbon source may include one or more of H ₃ SiCH ₃ , (H ₃ Si) ₄ C, CH ₄ , H ₃ GeCH ₃ , and (H ₃ Ge) ₂ CH ₂ . The silicon and/or carbon precursor or other suitable precursor may be mixed with a carrier gas and optionally with one or more other precursors as described herein. Step 212 may include selective deposition without the use of an etchant during or before step 212.

[41] The method 200 may further include forming an insulating layer placed on the substrate and forming a via in the insulating layer. Exemplary techniques for forming the insulating layer and vias within the insulating layer are described in greater detail below. In this case, the germanium-tin layer is applied to the substrate within the via (e.g., without the use of the additional step of exposing the substrate to an etchant to selectively deposit the germanium-tin film) as described below. It can be formed selectively on the phase.

[42] Figure 3 shows another method 300 according to additional embodiments of the present disclosure. Method 300 includes providing a vapor phase reactor (step 302), providing a substrate within a reaction chamber of the vapor phase reactor (step 304), and using one or more precursors comprising germaine on the surface of the substrate. Step 306 of forming a crystalline layer comprising, consisting essentially of, or consisting of germanium tin. Similar to method 200, method 300 provides (e.g., selectively) forms germanium-tin layers without requiring an etchant during or prior to forming a crystalline layer comprising germanium tin. can be used

[43] During step 302, a reactor suitable for growing a crystalline layer comprising germanium tin is provided. The reactor may include any reactor described herein, such as a horizontal-flow epitaxial CVD reactor.

[44] During step 304, a substrate is provided within the reaction chamber of the reactor. Step 304 may be the same or similar to step 208 of method 200.

[45] In step 308, a crystalline layer comprising germanium tin is formed. In accordance with various aspects of exemplary embodiments of the present disclosure, the step of forming a layer comprising tin germanium includes a germanium content of about 0.001 to about 0.1, about 0.005 to about 0.05, less than about 0.1, or less than about 0.05. and providing a mixture of tin precursor and germane having a volume ratio of tin precursor to: According to other aspects, the reaction chamber temperature during the step of forming the crystalline layer comprising germanium tin ranges from about 200°C to about 500°C, from about 250°C to about 450°C, or from about 300°C to about 420°C. am. And, according to still other aspects, the reaction chamber pressure during the step of forming the layer comprising tin germanium is from about 300 Torr to about 850 Torr, about 400 Torr to about 800 Torr, about 500 Torr to about 760 Torr, ambient atmospheric pressure ± about 20 Torr. , ambient atmospheric pressure ± about 10 Torr, or ambient atmospheric pressure ± about 5 Torr.

[46] Step 306 may include forming a layer comprising silicon germanium tin. In this case, a silicon precursor is provided to the reaction chamber. Exemplary silicon source precursors include disilane, trisilane, tetrasilane, neopentasilane, and higher order silane compounds. Additionally or alternatively, step 306 includes forming a germanium tin layer comprising carbon. Exemplary carbon precursors include one or more of H ₃ SiCH ₃ , (H ₃ Si) ₄ C, CH ₄ , H ₃ GeCH ₃ , and (H ₃ Ge) ₂ CH ₂ .

[47] Method 300 may also include forming an insulating layer overlying a substrate (step 308) and forming a via within the insulating layer (step 310). During step 308, any suitable insulating layer, such as silicon oxide or silicon nitride, may be deposited on the substrate. Then, during step 310, one or more vias may be formed in the insulating layer. Reactive ion etching or other suitable techniques may be used to form one or more vias.

[48] When steps 308 and 310 are performed, the crystalline layer formed during step 306 may be selectively formed within the via. As mentioned above, the germane precursor is advantageous because it is relatively selective when using various carrier gases such as hydrogen and when the layer contains one or more dopants such as p-type dopants. As mentioned above, method 300 can be used to selectively deposit germanium-tin films without requiring the use of an etchant.

[49] Layers formed using method 200 or method 300 (e.g., during step 212 or step 306) may have, for example, greater than 1 at%, greater than 2 at%, or greater than 5 at%, or from about 0 at%. It may include about 15 at% tin, about 2 at% to about 15 at% tin, about 0.2 at% to about 5 at% tin, or about 0.2 at% to about 15 at% tin. When the germanium tin crystalline layer includes silicon, the layer has greater than 0 at% silicon, greater than about 1 at% silicon, or about 1 at% silicon to about 20 at% silicon, about 2 at% to about 16 at% silicon, or about 4 at% silicon. % silicon to about 12 at % silicon. If the films contain carbon, they may contain additional tin. Exemplary germanium tin films comprising carbon may include about 0.2 to about 20 at% tin, about 0 to about 20 at% silicon, and about 0 to about 10 at% carbon.

[50] Figure 4 shows a transmission electron microscope image of a structure 400 formed according to various embodiments of the invention, such as method 200 or method 300. Structure 400 includes a silicon substrate 402, a germanium buffer layer 404 overlying substrate 402, and a germanium-tin layer 406 formed using germanium as a precursor. In the example shown, layer 406 includes approximately 8 at% tin. No threading defects were observed in the structure shown.

[51] Figure 5 shows a rocking scan of a structure such as structure 400. The scan shows discrete peaks associated with the germanium tin layer, the germanium layer, and the silicon substrate. As shown, the germanium-tin peak is associated with Pendellosung fringes, indicating a high degree of crystallinity in the germanium-tin layer.

[52] Referring now to Figure 6, a structure 600 is shown in accordance with additional example embodiments of the present disclosure. Structure 600 includes a substrate 602, an insulating layer 604, a via 606 formed within the insulating layer 604, and a germanium layer 608 (e.g., epitaxially grown to lie on the substrate 602). ), and a germanium-tin layer 610 (e.g., epitaxially grown to overlie layer 608). Layer 608 and/or layer 610 may optionally be formed within via 606 (e.g., using method 200 or method 300).

[53] Figure 7 shows another structure 700 according to additional embodiments of the present disclosure. Structure 700 includes a substrate 702, a first layer (e.g., a germanium-silicon-tin layer, a germanium-silicon-carbon-tin layer, a germanium tin layer, a germanium-silicon layer, or a germanium tin layer). one or more of the layers) 704, a germanium-tin layer 706, and a second layer (e.g., a germanium-silicon-tin layer, a germanium-silicon-carbon-tin layer, a germanium tin layer, a germanium tin layer, one or more of a nium-silicon layer, or a germanium layer) 708. In the example shown, a germanium-tin layer 706 is between the first layer 704 and the second layer 708; Layer 704 and layer 708 may include the same material or different materials (with the same or different compositions). Table 1 below shows example combinations of layer 704 and layer 708 materials.

yes Floor (704) Floor(708) One GeSiCSn GeSiCSn 2 GeSn _x GeSn _y (x≠y) 3 GeSi _x GeSi _y (x≠y) 4 Ge Ge

[54] Layers 704-708 may be formed according to methods described herein. Additionally, although not shown, one or more layers 704-708 may be formed within the via of the insulating material, as described above with reference to FIG. 6. For example, first layer 704 may include GeSn _x and second layer 708 may include GeSn _y , where x and y are not the same.

[55] It should be understood that the configurations and/or approaches described herein are illustrative in nature, and the specific embodiments or examples should not be taken in a limiting sense. Particular routines or methods described herein may represent one or more of any number of processing strategies. Accordingly, the various acts shown may be performed according to the order shown, according to different orders, performed simultaneously, or in some cases may be omitted.

[56] The subject matter of the present disclosure is to include all novel and non-obvious combinations and subcombinations and other features, functions, acts, and other features, functions, and acts of the various processes, systems, and configurations disclosed herein. and/or attributes, as well as any and all equivalents thereof.

Claims (20)

providing a gas phase reactor;
providing a germane source connected to the gas phase reactor;
providing a tin precursor source connected to the gas phase reactor;
providing a substrate within a reaction chamber of the gas phase reactor;
providing germane and tin precursors to the reaction chamber, wherein the ratio of the tin precursor to germane is less than 0.1;
Providing a carbon precursor selected from the group consisting of (H ₃ Si) ₄ C, CH ₄ , H ₃ GeCH ₃ , and (H ₃ Ge) ₂ CH ₂ to the gas phase reactor; and
forming a crystalline germanium tin layer on the surface of the substrate in a reaction chamber at a pressure of 300 Torr to 850 Torr,
A method of forming a crystalline germanium-tin layer, wherein the germanium tin layer includes carbon. According to claim 1,
wherein the crystalline germanium tin layer includes silicon,
A method of forming a crystalline germanium-tin layer, wherein the method further comprises providing a silicon source precursor. According to clause 2,
The step of providing a silicon source precursor includes providing a precursor selected from the group consisting of disilane, trisilane, tetrasilane, and neopentasilane. A method of forming a crystalline germanium-tin layer, characterized in that: According to claim 1,
A method of forming a crystalline germanium-tin layer, wherein the operating pressure of the reaction chamber during the step of growing the crystalline germanium-tin layer on the surface of the substrate is 400 Torr to 800 Torr. According to claim 1,
A method of forming a crystalline germanium-tin layer, wherein the operating pressure of the reaction chamber during the step of growing the crystalline germanium-tin layer on the surface of the substrate is 500 Torr to 760 Torr. According to claim 1,
A method of forming a crystalline germanium-tin layer, wherein the operating pressure of the reaction chamber during the step of growing the crystalline germanium-tin layer on the surface of the substrate is ambient atmospheric pressure ± 20 Torr. According to claim 1,
A method of forming a crystalline germanium-tin layer, characterized in that the ratio of the tin precursor to the germanium is 0.001 to 0.1. According to claim 1,
A method of forming a crystalline germanium-tin layer, characterized in that the operating temperature in the reaction chamber during the step of growing the crystalline germanium-tin layer on the surface of the substrate is 200° C. to 500° C. According to claim 1,
A method of forming a crystalline germanium-tin layer, characterized in that the operating temperature in the reaction chamber during the step of growing the crystalline germanium-tin layer on the surface of the substrate is 250° C. to 450° C. According to claim 1,
The step of providing the tin precursor source includes providing a tin source selected from the group consisting of SnCl ₄ , SnD ₄ , and methyl and halide substituted tin compounds. -How to form a tin layer. According to claim 1,
said step of growing a crystalline germanium tin layer on the surface of said substrate comprising growing a crystalline layer comprising between 0.2 at% (atomic percent) and 20 at% tin. How to form . According to claim 1,
A method of forming a crystalline germanium-tin layer, wherein the carbon precursor is selected from one or more of CH ₄ , H ₃ GeCH ₃ , and (H ₃ Ge) ₂ CH ₂ . providing a gas phase reactor;
providing a substrate to a reaction chamber of the gas phase reactor; and
forming a crystalline layer comprising germanium tin and carbon on the surface of the substrate using one or more precursors comprising germanium and carbon precursors, wherein the pressure in the reaction chamber is from 300 Torr to 850 Torr,
The carbon precursor has a structure including a germanium-tin layer, characterized in that it is selected from the group consisting of (H ₃ Si) ₄ C, CH ₄ , H ₃ GeCH ₃ , and (H ₃ Ge) ₂ CH ₂ How to form. According to claim 13,
A method of forming a structure comprising a germanium-tin layer, wherein the substrate comprises a layer comprising germanium overlying silicon. According to claim 13,
A method of forming a structure comprising a germanium-tin layer, wherein the germanium-tin layer contains 0.2 at% tin to 20 at% tin. According to claim 13,
A method of forming a structure comprising a germanium-tin layer, wherein the forming step does not include exposing the substrate to an etchant. According to claim 13,
A method of forming a structure comprising a germanium-tin layer, wherein the substrate comprises a layer comprising germanium silicon tin deposited on silicon. According to claim 13,
forming an insulating layer placed on the substrate;
forming a via in the insulating layer; and
further comprising selectively forming the crystalline layer comprising germanium tin and carbon within the via,
A method of forming a structure comprising a germanium-tin layer, wherein the crystalline layer comprising germanium tin and carbon comprises silicon, up to 10 at% carbon, and 0.2 to 20 at% tin. delete delete

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