Semiconductor device and method for manufacturing semiconductor device

Abstract

This invention provides a high-performance semiconductor device and a method for manufacturing the semiconductor device. The semiconductor device includes an active layer and a barrier layer stacked on the active layer. The active layer contains arsenic or antimony, and the barrier layer contains aluminum. The direction in which the barrier layer is stacked on the active layer is set as the depth direction. In the atomic concentration distribution along the depth direction from the active layer to the barrier layer, the rising position of hydrogen concentration is closer to the center of the active layer than the rising position of aluminum concentration.

Description

Technical Field

[0001] This disclosure relates to semiconductor devices and methods for manufacturing semiconductor devices. Background Technology

[0002] Compound semiconductors containing InSb or InAs are materials with high mobility and small band gaps. Utilizing these characteristics, compound semiconductors containing InSb or InAs are used in devices such as magnetic sensors, high-speed devices, and IR (infrared) sensors. For example, to realize devices using compound semiconductors containing InSb, AlInSb is preferably used as an electron blocking layer.

[0003] For example, Patent Document 1 discloses a compound semiconductor substrate containing an AlInSb layer with good crystallinity and excellent surface flatness, manufactured using Metal Organic Chemical Vapor Deposition (MOCVD).

[0004] [Existing Technical Documents]

[0005] [Patent Documents]

[0006] Patent Document 1: Japanese Patent Application Publication No. 2018-104278 Summary of the Invention

[0007] [The problem the invention aims to solve]

[0008] Here, semiconductor devices, for example, are used as IR light-emitting devices or IR light-receiving devices, requiring further improvements in luminous intensity or detection sensitivity. In other words, semiconductor devices require higher SNR (Signal to Noise Ratio) in practical applications.

[0009] The present invention was made in view of the above circumstances, and its purpose is to provide a high-performance semiconductor device and a method for manufacturing the semiconductor device.

[0010] [Methods used to solve problems]

[0011] (1) In a semiconductor device according to one embodiment of the present disclosure,

[0012] The semiconductor device includes an active layer and a barrier layer stacked on the active layer.

[0013] The active layer contains arsenic or antimony.

[0014] The barrier layer comprises aluminum.

[0015] When the direction in which the barrier layer is stacked on the active layer is defined as the depth direction, in the atomic concentration distribution along the depth direction from the active layer to the barrier layer, the rising position of hydrogen concentration is closer to the center of the active layer than the rising position of aluminum concentration.

[0016] (2) As one embodiment of this disclosure, in (1),

[0017] The active layer contains indium.

[0018] (3) As one embodiment of this disclosure, in (2),

[0019] The active layer contains indium and antimony.

[0020] (4) As one embodiment of this disclosure, in (2),

[0021] The active layer contains indium and arsenic.

[0022] (5) As one embodiment of this disclosure, in any one of (1) to (4),

[0023] The barrier layer contains antimony.

[0024] (6) As one embodiment of this disclosure, in any one of (1) to (5),

[0025] In the atomic concentration distribution along the depth direction from the active layer to the barrier layer, the hydrogen concentration becomes less than 50% of the concentration at the peak after reaching a peak.

[0026] (7) As one embodiment of this disclosure, in any one of (1) to (6),

[0027] In the atomic concentration distribution along the depth direction from the active layer to the barrier layer, the peak position of the hydrogen concentration is located within a range of less than 30 nm offset from the interface between the barrier layer and the active layer towards the active layer side.

[0028] (8) As one embodiment of this disclosure, in any one of (1) to (7),

[0029] In the atomic concentration distribution along the depth direction from the active layer to the barrier layer, the half-width of the peak hydrogen concentration is less than 60 nm.

[0030] (9) As one embodiment of this disclosure, in any one of (1) to (8),

[0031] In the atomic concentration distribution along the depth direction of the barrier layer, the hydrogen concentration at the other end is lower than that at the end adjacent to both the barrier layer and the active layer.

[0032] (10) As one embodiment of this disclosure, in (9),

[0033] The barrier layer is doped with n-type or p-type atoms, and in the atomic concentration distribution along the depth direction of the barrier layer, when the hydrogen concentration distribution is approximated using a linear or quadratic function, the hydrogen concentration decreases monotonically from one end to the other end.

[0034] (11) As one embodiment of this disclosure, in any one of (1) to (10),

[0035] The barrier layer is doped into n-type or p-type.

[0036] (12) As one embodiment of this disclosure, in any one of (1) to (11),

[0037] The active layer and the barrier layer have different lattice constants in the unstrained state.

[0038] (13) As one embodiment of this disclosure, in any one of (1) to (12),

[0039] The active layer also contains aluminum.

[0040] (14) A method for manufacturing a semiconductor device according to one embodiment of the present invention, wherein the semiconductor device described in any one of (1) to (13) is manufactured, wherein,

[0041] Before the barrier layer is formed into a film, a pressure rise annealing process is included, in which the pressure of the reaction chamber of the apparatus is increased to perform annealing.

[0042] (15) In a semiconductor device according to one embodiment of the present disclosure

[0043] The semiconductor device includes an active layer and a barrier layer stacked on the active layer.

[0044] The active layer contains arsenic or antimony.

[0045] The barrier layer contains aluminum and either arsenic or antimony.

[0046] When the direction in which the barrier layer is stacked on the active layer is defined as the depth direction, in the atomic concentration distribution along the depth direction from the active layer to the barrier layer, the rising position of hydrogen concentration is closer to the center of the active layer than the rising position of aluminum concentration.

[0047] (16) As one embodiment of this disclosure, in (15),

[0048] The active layer contains indium.

[0049] (17) As one embodiment of this disclosure, in (16),

[0050] The active layer contains indium and antimony.

[0051] (18) As one embodiment of this disclosure, in (16),

[0052] The active layer contains indium and arsenic.

[0053] (19) As one embodiment of this disclosure, in (15),

[0054] The barrier layer contains antimony.

[0055] (20) As one embodiment of this disclosure, in (15),

[0056] In the atomic concentration distribution along the depth direction from the active layer to the barrier layer, the hydrogen concentration becomes less than 50% of the concentration at the peak after reaching a peak.

[0057] (21) As one embodiment of this disclosure, in (20),

[0058] In the atomic concentration distribution along the depth direction from the active layer to the barrier layer, the peak position of the hydrogen concentration is located within a range of less than 30 nm offset from the interface between the barrier layer and the active layer towards the active layer side.

[0059] (22) As one embodiment of this disclosure, in (20),

[0060] In the atomic concentration distribution along the depth direction from the active layer to the barrier layer, the half-width of the peak hydrogen concentration is less than 60 nm.

[0061] (23) As one embodiment of this disclosure, in (15),

[0062] In the atomic concentration distribution along the depth direction of the barrier layer, the hydrogen concentration at the other end is lower than that at the end adjacent to both the barrier layer and the active layer.

[0063] (24) As one embodiment of this disclosure, in (23),

[0064] The barrier layer is doped with n-type or p-type atoms, and in the atomic concentration distribution along the depth direction of the barrier layer, when the hydrogen concentration distribution is approximated using a linear or quadratic function, the hydrogen concentration decreases monotonically from one end to the other end.

[0065] (25) As one embodiment of this disclosure, in (15),

[0066] The barrier layer is doped into n-type or p-type.

[0067] (26) As one embodiment of this disclosure, in (15),

[0068] The active layer and the barrier layer have different lattice constants in the unstrained state.

[0069] (27) As one embodiment of this disclosure, in (15),

[0070] The active layer also contains aluminum.

[0071] (28) A method for manufacturing a semiconductor device according to one embodiment of the present invention, comprising manufacturing the semiconductor device described in any one of (15) to (27), wherein,

[0072] Before the barrier layer is formed into a film, a pressure rise annealing process is included, in which the pressure of the reaction chamber of the apparatus is increased to perform annealing.

[0073] (29) In a semiconductor device according to one embodiment of the present disclosure

[0074] The semiconductor device includes an active layer and a barrier layer adjacent to the active layer.

[0075] The active layer contains indium and antimony.

[0076] The barrier layer comprises aluminum, indium, and antimony.

[0077] When the direction in which the barrier layer is stacked on the active layer is set as the depth direction, in the atomic concentration distribution along the depth direction from the active layer to the barrier layer, the rising position of hydrogen concentration is closer to the active layer side than the rising position of aluminum concentration.

[0078] (30) As one embodiment of this disclosure, in (29),

[0079] In the atomic concentration distribution along the depth direction from the active layer to the barrier layer, the hydrogen concentration becomes less than 50% of the concentration at the peak after reaching a peak.

[0080] (31) As one embodiment of this disclosure, in (30),

[0081] In the atomic concentration distribution along the depth direction from the active layer to the barrier layer, the peak position of the hydrogen concentration is located within a range of less than 30 nm offset from the interface between the barrier layer and the active layer towards the active layer side.

[0082] (32) As one embodiment of this disclosure, in (29),

[0083] In the atomic concentration distribution along the depth direction from the active layer to the barrier layer, the half-width of the peak hydrogen concentration is less than 60 nm.

[0084] (33) As one embodiment of this disclosure, in (29),

[0085] In the atomic concentration distribution along the depth direction of the barrier layer, the hydrogen concentration at the other end is lower than that at the end adjacent to both the barrier layer and the active layer.

[0086] (34) As one embodiment of this disclosure, in (33),

[0087] The barrier layer is doped, and in the atomic concentration distribution along the depth direction of the barrier layer, the hydrogen concentration monotonically decreases from one end to the other end.

[0088] (35) As one embodiment of this disclosure, in (30) or (33),

[0089] The barrier layer is doped.

[0090] (36) As one embodiment of this disclosure, in (30) or (33),

[0091] The active layer and the barrier layer have different lattice constants in the unstrained state.

[0092] (37) As one embodiment of this disclosure, in (29),

[0093] The active layer also contains aluminum.

[0094] (38) A method for manufacturing a semiconductor device according to one embodiment of the present invention, wherein the semiconductor device described in any one of (29) to (34) is manufactured, wherein,

[0095] Before the barrier layer is formed into a film, a pressure rise annealing process is included, in which the pressure of the reaction chamber of the apparatus is increased to perform annealing.

[0096] [Invention Effects]

[0097] According to this disclosure, a high-performance semiconductor device and a method for manufacturing the semiconductor device can be provided. Attached Figure Description

[0098] Figure 1 This is a graph illustrating an example of the distribution of aluminum and hydrogen concentrations in a semiconductor device according to an embodiment of the present invention.

[0099] Figure 2 This is a graph showing the defect dependence of the resistance of a semiconductor device when it is an infrared device.

[0100] Figure 3 This is a diagram showing the energy band structure of a semiconductor device when it is used as an infrared device.

[0101] Figure 4 This is a graph showing the defect quantity dependence of mobility when the semiconductor device is a Hall element.

[0102] Figure 5 This is a diagram showing the energy band structure when the semiconductor device is a Hall element.

[0103] Figure 6 The structure of a semiconductor device is illustrated by a diagram showing the distribution of aluminum and hydrogen concentrations.

[0104] Figure 7 It is a diagram used to illustrate dangling bonds and termination caused by hydrogen.

[0105] Figure 8 This is a diagram showing the energy band structure when the semiconductor device is a Hall element.

[0106] Figure 9 This is a diagram showing the energy band diagram of embodiment A.

[0107] Figure 10 This is a diagram representing the band structure of comparative example A.

[0108] Figure 11 This is a diagram showing the energy band diagram of Example B.

[0109] Figure 12 This is a diagram representing the band structure of Comparative Example B.

[0110] Figure 13 This is a diagram showing the energy band diagram of embodiment C.

[0111] Figure 14 This is a diagram representing the band structure of comparative example C.

[0112] Figure 15 This is a diagram showing the energy band diagram of embodiment D.

[0113] Figure 16 This is a diagram representing the band structure of comparative example D. Detailed Implementation

[0114] Semiconductor Devices

[0115] The semiconductor device of this embodiment includes an active layer and a barrier layer stacked on the active layer. Figure 6The left figure illustrates the structure of a semiconductor device. The semiconductor device may include a substrate. Furthermore, the semiconductor device may include: a first layer disposed between the substrate and the active layer; and a second layer adjacent to a barrier layer on the side opposite to the active layer. At least one of the first and second layers may be omitted depending on the type of semiconductor device. The semiconductor device is constructed by stacking these layers, including at least the active layer and the barrier layer. Hereinafter, the direction in which the barrier layer is stacked over the active layer will be referred to as the depth direction, and the positions of the constituent elements will be explained.

[0116] Here, the semiconductor device can be an infrared device (IR device). An infrared device is a general term encompassing both infrared light-emitting elements and infrared light-receiving elements. The infrared light-emitting element is implemented using the structure of the semiconductor device described below, and the infrared light-receiving element is implemented using the same structure. Specifically, when the semiconductor device is an infrared light-emitting element, it can be a light-emitting diode (LED). Specifically, when the semiconductor device is an infrared light-receiving element, it can be a photodiode (PD). Alternatively, the semiconductor device can be a Hall element. The case where the semiconductor device is a Hall element will be described in one of the embodiments described later. In other descriptions of this embodiment, the semiconductor device will be described as an infrared device.

[0117] <Active Layer>

[0118] The active layer can be configured to contain arsenic (As) or antimony (Sb). Therefore, InAs or InSb are used as materials for the active layer, but it is not limited to these. The active layer can also contain aluminum (Al). Therefore, InAlSb and other materials can be used as materials for the active layer, but it is not limited to these. In addition, the active layer can contain atoms such as gallium (Ga), or it can be composed of alloys containing them. In addition, the active layer is not limited to the above-mentioned materials, and other materials can be used. Furthermore, from the viewpoint of device characteristics, the active layer is preferably a single crystal. In addition, when the active layer contains indium, due to the band bending, electrons tend to accumulate at the interface between the active layer and the barrier layer, and the termination effect generated by hydrogen, described later, is greater.

[0119] <Blocking Layer>

[0120] The barrier layer is composed of aluminum (Al) and may also contain arsenic (As) or antimony (Sb). The barrier layer functions as an energy barrier against electrons or holes in the active layer. Therefore, materials such as InAlSb are used as the barrier layer, but are not limited to these. The barrier layer preferably forms an energy barrier against electrons or holes in the active layer. Furthermore, the barrier layer may contain atoms such as gallium (Ga) or may be composed of alloys containing them. From the viewpoint of device characteristics, the barrier layer is preferably a single crystal. Additionally, the lattice constant of the barrier layer material is preferably close to that of the active layer material. In order to form an energy barrier against electrons or holes without significantly changing the lattice constant relative to the active layer, it is preferable to include a material in the barrier layer in which aluminum is incorporated into the material constituting the active layer. Furthermore, when the barrier layer contains antimony, due to band bending, electrons tend to accumulate at the interface between the active layer and the barrier layer, resulting in a greater termination effect from hydrogen, as described later.

[0121] <Substrate>

[0122] There are no particular restrictions on the substrate as long as it supports layers including the active layer and the barrier layer. Examples include GaAs substrates, InP substrates, GaN substrates, Si substrates, quartz substrates, aluminum substrates, oxide substrates, aluminum nitride substrates, and polyimide flexible substrates.

[0123] <First Layer>

[0124] The first layer can be, for example, a semiconductor layer of a first conductivity type. The first conductivity type can be, for example, n-type. As the constituent material of the first layer, InSb, GaAs, InAs, InGaAs, InAlSb, GaAsSb, or InGaP are used, but it is not limited to these. In addition, it is preferable that the band gap of the first layer is larger than that of the active layer, forming an energy barrier for electrons or holes in the active layer.

[0125] <Second Layer>

[0126] The second layer can be, for example, a semiconductor layer of a second conductivity type. The second conductivity type is different from the first conductivity type, for example, it can be p-type. As another example, the first conductivity type can be p-type, and the second conductivity type can be n-type. As the constituent material of the second layer, InSb, GaAs, InAs, InGaAs, InAlSb, GaAsSb, or InGaP are used, but it is not limited to these.

[0127] <Hydrogen Concentration Distribution>

[0128] As mentioned above, higher SNR is required for semiconductor devices. The inventors conducted in-depth research on methods to provide high-performance semiconductor devices and found that performance can be improved through proper termination of dangling bonds.

[0129] Figure 7 It is a diagram used to illustrate dangling bonds and termination caused by hydrogen. Figure 7 The central image is of a semiconductor device, and... Figure 6 The same. The lattice constants of the active layer and the barrier layer are different in the unstrained state. Figure 7 (Left figure). Therefore, at the boundary between the active layer and the barrier layer, dangling bonds are easily formed due to the difference in lattice constants (the number of defects tends to increase). Here, hydrogen can terminate the dangling bonds ( Figure 7 (See the right figure). That is, hydrogen can reduce unbonded bonds and lower the defect energy level. The barrier layer sometimes contains hydrogen (H), and the distribution of hydrogen concentration can be adjusted by adjusting the process steps of the semiconductor device manufacturing method. In the semiconductor device of this embodiment, hydrogen terminates defects near the interface between the barrier layer and the active layer, lowers the defect energy level, and thus enables a high SNR.

[0130] Figure 1 This example illustrates the distribution of aluminum and hydrogen concentrations in the semiconductor device of this embodiment. Measurements were performed using a SIMS (Secondary Ionization Mass Spectrometer). Specifically, an "IMS-7f" manufactured by CAMECA, a sector-type SIMS device, was used. The ion species in the primary ion beam was Cs. + The primary ion beam acceleration voltage is 15 kV. Additionally, the secondary ion detection polarity is cathode (negative). Figure 1 The horizontal axis is "depth", which is like... Figure 6 This is the depth distance in the direction from the semiconductor device surface (the surface furthest from the substrate in the layer furthest from the substrate) set to zero. Additionally, the vertical axis represents the normalized concentration. Aluminum concentration is normalized by dividing by the peak (maximum) value of aluminum concentration. Similarly, hydrogen concentration is normalized by dividing by the peak (maximum) value of hydrogen concentration. Figure 1 As shown, the peak value of hydrogen concentration deviates from the peak value of aluminum concentration, which can be said to be shifted towards the active layer side (center). The following describes the appropriate distribution of atomic concentration along the depth direction from the active layer to the barrier layer of the semiconductor device.

[0131] First, to efficiently terminate defect energy levels, and because hydrogen atoms sometimes deactivate dopants, the local presence of hydrogen atoms is preferred. This is especially true when the semiconductor device is an infrared device, which is sometimes doped with a barrier layer. If hydrogen atoms deactivate the dopants in the barrier layer, parasitic resistance can increase. Therefore, by limiting the range of hydrogen atoms present in the barrier layer, high-performance devices with low parasitic resistance and the ability to terminate interface defects can be achieved. Specifically, it is important that hydrogen atoms are abundantly distributed in the region near the active layer and the barrier layer. Here, not only at the interface between the active layer and the barrier layer, but also in the region (approximately tens of nm) near the barrier layer within the active layer, carriers tend to accumulate due to band bending (conduction band, valence band). Therefore, a structure that increases hydrogen concentration not only at the interface but also in the region near the barrier layer within the active layer is preferred.

[0132] Here, Figure 6 The illustration of a semiconductor device's structure is shown in a graph representing the schematic distribution of aluminum and hydrogen concentrations. This schematic distribution is represented by a Gaussian function. Figure 1 Such a detailed distribution is approximated. The rising position is the inflection point in an approximate Gaussian function that leads from the active layer toward the blocking layer (in the opposite direction of depth) to the peak.

[0133] In addition to the Gaussian function, an exponential function term can be used to approximate the tail observed in SIMS measurements in the approximation of the concentration distribution. The tail refers to the apparent concentration expansion caused by artifacts accompanying sputtering or secondary ion generation processes. It is known that the signal has an edge in the depth direction when performing SIMS measurements. When approximating the tail using an exponential function term, the rising position is also represented by the inflection point in the Gaussian function component. Specifically, in the case of SIMS measurements in the depth direction, it can be approximated by the following equations (1) to (3).

[0134] Formula 1

[0135]

[0136]

[0137]

[0138] Here, z is the coordinate in the depth direction. C meas The atomic concentration was determined by SIMS analysis. C gaus It is a Gaussian function representing atomic concentration. (C) tailThis is a function representing the effect of the tailing. z1 is a parameter representing the peak center of the Gaussian function. σ is a parameter representing the expansion of the Gaussian function. z2 is a parameter representing the coordinates at which the tailing begins. λ is a parameter representing the extent of the tailing expansion. A1 and A2 are coefficients.

[0139] Furthermore, to smoothly represent the area near where the tail begins to appear, a smoothed switching function S, as shown in equations (4) and (5), can be used to approximate the tail instead of equation (3). In this case, the rising position is also represented by the inflection point in the components of the Gaussian function. Here, α in equation (5) is a parameter representing the degree of smoothness.

[0140] Formula 2

[0141]

[0142]

[0143] Furthermore, when the distribution does not have a clearly defined peak shape, a portion of the distribution can be used for approximation. For example, regarding the aluminum concentration when the barrier layer has a certain thickness, after increasing from the active layer towards the barrier layer (in the opposite direction to the depth) in the region corresponding to the interface, it continues to take a certain value in the region corresponding to the barrier layer. Regarding the distribution of this aluminum concentration, only the portion increasing in the region corresponding to the interface can be used for approximation using a Gaussian function.

[0144] In this embodiment, the semiconductor device exhibits a hydrogen concentration increase position closer to the active layer side than an aluminum concentration increase position in the atomic concentration distribution along the depth direction from the active layer to the barrier layer. Here, "closer to the active layer side" can mean close to the center of the active layer. Alternatively, "closer to the active layer side" can mean close to the first layer or close to the substrate. By having this hydrogen and aluminum distribution, the semiconductor device achieves a high SNR because hydrogen atoms terminate defects and lower the defect energy level.

[0145] Furthermore, from the viewpoint of allowing hydrogen atoms to exist locally, in the distribution of atomic concentration in the depth direction from the active layer to the barrier layer, after the hydrogen concentration reaches its peak, it is preferable to be less than 70% of the concentration at the peak, and more preferably less than 50%.

[0146] Furthermore, in the atomic concentration distribution along the depth direction from the active layer to the barrier layer, the peak position of the hydrogen concentration is preferably at the interface between the barrier layer and the active layer. However, the peak position of the hydrogen concentration only needs to be within a range of less than 30 nm offset from the interface towards the active layer side. Here, the interface between the barrier layer and the active layer can be defined by a plane corresponding to the rising position of the atoms (e.g., aluminum) contained in the barrier layer.

[0147] Furthermore, from the viewpoint of allowing hydrogen atoms to exist locally, the half-width of the peak value of hydrogen concentration is preferably 60 nm or less in the atomic concentration distribution along the depth direction from the active layer to the barrier layer. From the viewpoint of efficient defect termination caused by hydrogen, the half-width of the peak value of hydrogen concentration is preferably 1 nm or more.

[0148] Furthermore, from the viewpoint of allowing hydrogen atoms to exist locally, a low hydrogen concentration in the barrier layer is preferred. Therefore, in the atomic concentration distribution along the depth direction of the barrier layer, the barrier layer is preferably configured such that the hydrogen concentration at one end adjacent to the active layer is lower than that at the other end. Furthermore, it is even more preferable that the barrier layer is doped such that the hydrogen concentration monotonically decreases from one end to the other in the atomic concentration distribution along the depth direction of the barrier layer. Here, monotonically decreasing means monotonically decreasing when the detailed distribution is approximated by a linear or quadratic function.

[0149] Here, when the barrier layer is used as an electron barrier layer, p-type doping is preferred. Conversely, when the barrier layer is used as a hole barrier layer, n-type doping is preferred. However, from the viewpoint of preventing dopant deactivation, a low hydrogen concentration in the barrier layer is preferable when using a doped barrier layer.

[0150] <Semiconductor Device Manufacturing Methods>

[0151] The inventors conducted research and found that a semiconductor device having the aforementioned hydrogen concentration distribution can be manufactured based on the manufacturing method of Patent Document 1 by performing a pressure-increasing annealing process to increase the pressure of the reaction chamber of the apparatus before forming the barrier layer. Hereinafter, a process example for manufacturing the semiconductor device of this embodiment will be described. Furthermore, in order to locally contain hydrogen atoms, the aforementioned semiconductor device can also be manufactured by increasing the hydrogen flow rate based on the manufacturing method of Patent Document 1.

[0152] The multilayer film was prepared using MOCVD as described below. First, a zincblende type semi-insulating GaAs substrate was prepared. At a substrate temperature of 500°C, trimethylindium (TMIn) as the In raw material, tris(dimethylamino)antimony (TDMASb) as the Sb raw material, and dimethyltellurium (DMTe) as the n-doperant were supplied to the semi-insulating GaAs substrate to form an n-InSb layer. At this time, the ratio of the group V element supply to the group III element supply, i.e., the V / III ratio, was 5.0. The thickness of the n-InSb layer was 1000 nm. Furthermore, the doping concentration was 1.0 × 10⁻⁶. 19 / cm 3 .

[0153] Subsequently, at a substrate temperature of 500°C, trimethylindium (TMIn) as the In raw material, tris(dimethylamino)antimony (TDMASb) as the Sb raw material, and dimethylzinc (DMZn) as the p-doper, are supplied to form a p-InSb layer. At this point, the V / III ratio is 5.0. The p-InSb layer serves as the active layer. The thickness of the p-InSb layer is 2000 nm. Furthermore, the doping concentration is 6.0 × 10⁻⁶. 16 / cm 3 .

[0154] Here, with all sources of supply stopped and only hydrogen flowing into the reaction chamber, the pressure in the reaction chamber is increased from 50 torr to 300 torr. Annealing is then performed for 10 minutes under these conditions. The pressure in the reaction chamber is then reduced from 300 torr to 50 torr.

[0155] Next, at a substrate temperature of 500°C, tri-tert-butylaluminum (TTBAl) as the Al raw material, trimethylindium (TMIn) as the In raw material, and tris(dimethylamino)antimony (TDMASb) as the Sb raw material are supplied. Then, dimethylzinc (DMZn) is supplied as a p-doper to form a p-AlInSb layer. The p-AlInSb layer acts as a barrier layer. At this time, the Al raw material, In raw material, and Sb raw material are supplied together with an Al / (Al+In) ratio of 0.50. Then, in order to form Al... 0.7 In 0.3 Sb is added to increase the Al / (Al+In) ratio to 0.70 (i.e., to increase the supply of Al raw materials). At this point, the V / III ratio is 5.0. The thickness of the p-AlInSb layer is 40 nm. Furthermore, the doping concentration is 2.0 × 10⁻⁶. 18 / cm 3 .

[0156] Subsequently, at a substrate temperature of 500°C, trimethylindium (TMIn) as the In raw material, tris(dimethylamino)antimony (TDMASb) as the Sb raw material, and dimethylzinc (DMZn) as the p-doper, were supplied to form a p-InSb layer. At this time, the V / III ratio was 5.0. The thickness of the p-InSb layer was 250 nm. Furthermore, the doping concentration was 2.0 × 10⁻⁶. 18 / cm 3 .

[0157] <Ingredients>

[0158] In the above manufacturing method, there are no particular restrictions on the In, Sb, and Al raw materials, as long as they can form InSb and AlInSb layers. Examples of In raw materials include trimethylindium (TMIn) and triethylindium (TEIn). Examples of Sb raw materials include trimethylantimony (TMSb), triethylantimony (TESb), tris(dimethylamino)antimony (TDMASb), and triisopropylantimony (TIPSb). Examples of Al raw materials include trimethylamine allan (TMAAl), triisobutylaluminum (TIBAl), and dimethylaluminum hydride (DMAH). Additionally, examples of Al raw materials include dimethylethylamine allan (DMEAAl) and tri-tert-butylaluminum (TTBAl).

[0159] From the viewpoint of feedstock decomposition temperature, the preferred In feedstock is trimethylindium (TMIn), triethylindium (TEIn), or a combination thereof. From the viewpoint of long-term feedstock stability, the preferred Al feedstock is tri-tert-butylaluminum (TTBAl). From the viewpoint of suppressing carbon impurities, the preferred Sb feedstock is tris(dimethylamino)antimony (TDMASb).

[0160] In addition to the aforementioned raw materials, dopants can also be supplied to control conductivity. Examples of dopants include dimethyl zinc (DMZn), diethyl zinc (DEZn), dimethyl tellurium (DMTe), diethyl tellurium (DETe), tetramethyltin (TMSn), and tetraethyltin (TESn).

[0161] <Example 1>

[0162] For the two laminated film structures (a) and (b) described below, the resistance as an IR sensor (IR light-receiving device) is calculated. Here, the resistance of the IR sensor (bias voltage: no applied) is an important indicator determining thermal noise, and a larger value is preferred. The laminated film is manufactured according to the above-described process.

[0163] The laminated membrane structures (a) and (b) have an active layer and a barrier layer stacked on an n-InSb layer (corresponding to...). Figure 6 Above the first layer in the middle) and the p-InSb layer (corresponding to ... Figure 6 The second layer is a structure stacked on top of the barrier layer.

[0164] In the stacked film structure (a), the n-InSb layer has a thickness of 1000 nm and a doping concentration of 1.0 × 10⁻⁶. 19 / cm 3 The p-InSb layer, serving as the active layer, has a thickness of 2000 nm and a doping concentration of 6.0 × 10⁻⁶. 16 / cm 3 p-Al as a barrier layer 0.18 In 0.82The Sb layer has a thickness of 20 nm and a doping concentration of 2.0 × 10⁻⁶. 18 / cm 3 The p-InSb layer has a thickness of 500 nm and a doping concentration of 2.0 × 10⁻⁶. 18 / cm 3 .

[0165] In the stacked film structure (b), the n-InSb layer has a thickness of 1000 nm and a doping concentration of 1.0 × 10⁻⁶. 19 / cm 3 Undoped i-Al as the active layer 0.09 In 0.91 The Sb layer has a thickness of 2000 nm. The p-Al layer serves as a barrier layer. 0.27 In 0.73 The Sb layer has a thickness of 20 nm and a doping concentration of 2.0 × 10⁻⁶. 18 / cm 3 The p-InSb layer has a thickness of 500 nm and a doping concentration of 2.0 × 10⁻⁶. 18 / cm 3 The height of the energy barrier of the barrier layer relative to the active layer, which affects the resistance described later, is the same in both the laminated film structure (a) and the laminated film structure (b).

[0166] Figure 2 The defect dependence of the resistance of the laminated film structures (a) and (b) is shown. The resistance is calculated by varying the defect amount in the region (30 nm) near the barrier layer in the active layer. The resistance referred to here is the resistance to the current flowing longitudinally in the laminated film structure. Figure 2 The resistance along the vertical axis of the multilayer film structures (a) and (b) is normalized to 1 when the defect amount is 0.01. Figure 2 As shown, the resistivity is increased by reducing the amount of defects near the barrier layer of the active layer. This effect is more pronounced in the laminated film structure (b), i.e., when the active layer contains Al.

[0167] in addition, Figure 3 This is the band diagram of the stacked membrane structure (a), magnified to show the vicinity of the active layer and the barrier layer. Figure 3 The vertical axis represents the energy of Ec (bottom of the conduction band) and Ev (top of the valence band). Figure 3 The horizontal axis represents the position in the depth direction. In IR devices, the recombination current in the active layer is a crucial factor determining the resistance value. Approximately 30 nm (arrow portion) near the barrier layer in the active layer, the valence band bends. It can be inferred that holes tend to accumulate in this region, easily leading to a decrease in resistance due to recombination current.

[0168] <Example 2>

[0169] For the following laminated film structure, the electron mobility in the lateral direction (orthogonal to the depth direction) is calculated. Here, mobility is an important indicator determining the SNR of the Hall element, and a higher mobility is preferred. The laminated film is manufactured according to the above-described steps.

[0170] The laminated film structure in this embodiment is based on i-Al 0.1 In 0.9 Sb layer (corresponding to) Figure 6 The i-Al structure has an active layer and a barrier layer stacked on top of the first layer. 0.1 In 0.9 The Sb layer has a thickness of 100 nm and a mobility of 3000 cm⁻¹. 2 / Vs. The i-InSb layer, serving as the active layer, has a thickness of 100 nm and a diameter of 52000 cm. 2 / Vs mobility. i-Al as a barrier layer 0.1 In 0.9 The Sb layer has a thickness of 100 nm and a mobility of 3000 cm⁻¹. 2 / Vs.

[0171] Figure 4 This represents the defect quantity dependence of the mobility of a laminated film structure. The mobility referred to here is the mobility of current flowing laterally in the laminated structure. Changing the region near the barrier layer in the active layer (and...) Figure 3 Calculate the mobility using the same defect quantity (30nm). Figure 4 As shown, by reducing the amount of defects near the barrier layer of the active layer, the mobility of the laminated film is improved.

[0172] in addition, Figure 8 This is the energy band diagram of the stacked film structure in this embodiment, magnified to show the vicinity of the active layer and the barrier layer. Figure 8 The vertical axis represents the energy of Ec (the bottom of the conduction band). The conduction band diagram is important in electron mobility. Figure 8 The horizontal axis represents the position in the depth direction. It is speculated that the conduction band bends near the barrier layer in the active layer, making electrons prone to accumulation and susceptible to defects, thus leading to a decrease in mobility. Furthermore, Figure 5 This is an energy band diagram of the structure with the i-InSb layer of the active layer in Example 2 having a film thickness of 300 nm. Approximately 60 nm (arrow portion) near the barrier layer in the active layer, the conduction band bends. Therefore, it is presumed that electrons tend to accumulate in this region, easily leading to a decrease in mobility.

[0173] Here, especially when the barrier layer contains Sb, electrons tend to accumulate in the region near the barrier layer in the active layer due to conduction band bending, which easily leads to a decrease in mobility. Therefore, it is speculated that hydrogen termination has a greater effect. The reasons are explained below.

[0174] <Active layer of InAs>

[0175] Figure 9 (Example A) is an energy band diagram of a structure in which a 100-nm i-InAs layer as an active layer and a 500-nm i-AlSb layer as a blocking layer are stacked on a 500-nm i-AlSb layer, with the vicinity of the active layer and the blocking layer magnified. Figure 9 The vertical axis represents the energy of Ec (the bottom of the conduction band). In electron mobility, the diagram of the conduction band is important. It is speculated that the conduction band bends near the blocking layer in the active layer, electrons are easily accumulated, are easily affected by defects, and are likely to cause a decrease in mobility.

[0176] Figure 10 (Comparative Example A) is a structure in which a 100-nm i-InAs layer as an active layer and a 500-nm i-Al 0.2 In 0.8 As layer are stacked on a 500-nm i-InAs layer, with the vicinity of the active layer and the blocking layer magnified. 0.2 In 0.8 As layer, and the energy band diagram of the structure, with the vicinity of the active layer and the blocking layer magnified. Figure 10 The vertical axis represents the energy of Ec (the bottom of the conduction band). In electron mobility, the diagram of the conduction band is important. Near the blocking layer in the active layer, no bending of the conduction band like the accumulation of electrons was found.

[0177] <Active layer of InSb>

[0178] Figure 11 (Example B) is a structure in which a 100-nm i-InSb layer as an active layer and a 500-nm i-Al 0.2 In 0.8 Sb layer are stacked on a 500-nm i-InSb layer, with the vicinity of the active layer and the blocking layer magnified. 0.2 In 0.8 Sb layer, and the energy band diagram of the structure, with the vicinity of the active layer and the blocking layer magnified. Figure 11 The vertical axis represents the energy of Ec (the bottom of the conduction band). In electron mobility, the diagram of the conduction band is important. It is speculated that the conduction band bends near the blocking layer in the active layer, electrons are easily accumulated, are easily affected by defects, and are likely to cause a decrease in mobility.

[0179] Figure 12 (Comparative Example B) is a structure in which a 100-nm i-InSb layer as an active layer and a 500-nm i-Al 0.2 In 0.8 As layer are stacked on a 500-nm i-InSb layer, with the vicinity of the active layer and the blocking layer magnified. 0.2 In 0.8 As layer, and the energy band diagram of the structure, with the vicinity of the active layer and the blocking layer magnified. Figure 12The vertical axis represents the energy of Ec (the bottom of the conduction band). In electron mobility, the graph of the conduction band is important. Near the barrier layer in the active layer, no bending of the conduction band like the accumulation of electrons was found.

[0180] Here, especially when In is contained in the active layer, in the region near the barrier layer in the active layer, due to the bending of the conduction band, electrons are likely to accumulate, and it is easy to cause a decrease in mobility. Therefore, it is speculated that the effect of hydrogen termination is large. The reasons are described below.

[0181] <Sb-based active layer>

[0182] Figure 13 (Example C) is a band diagram of a structure in which a 100-nm i-InSb layer as an active layer and a 500-nm i-Al 0.2 In 0.8 Sb layer are stacked on a 500-nm i-AlSb layer, magnifying the vicinity of the active layer and the barrier layer. 0.2 In 0.8 The vertical axis represents the energy of Ec (the bottom of the conduction band). In electron mobility, the graph of the conduction band is important. It is speculated that the conduction band bends near the barrier layer in the active layer, electrons are likely to accumulate, are easily affected by defects, and it is easy to cause a decrease in mobility. Figure 13 The vertical axis represents the energy of Ec (the bottom of the conduction band). In electron mobility, the graph of the conduction band is important. It is speculated that the conduction band bends near the barrier layer in the active layer, electrons are likely to accumulate, are easily affected by defects, and it is easy to cause a decrease in mobility.

[0183] Figure 14 (Comparative Example C) is a band diagram of a structure in which a 100-nm i-GaSb layer as an active layer and a 500-nm i-AlSb layer as a barrier layer are stacked on a 500-nm i-AlSb layer, magnifying the vicinity of the active layer and the barrier layer. Figure 14 The vertical axis represents the energy of Ec (the bottom of the conduction band). In electron mobility, the graph of the conduction band is important. Near the barrier layer in the active layer, no bending of the conduction band like the accumulation of electrons was found. Here, in Example C and Comparative Example C, a material having a lattice constant relatively close to that of the active layer and a band gap larger than that of the active layer was selected as the barrier layer.

[0184] <As-based active layer>

[0185] Figure 15 (Example D) is a band diagram of a structure in which a 100-nm i-InAs layer as an active layer and a 500-nm i-AlSb layer as a barrier layer are stacked on a 500-nm i-AlSb layer, magnifying the vicinity of the active layer and the barrier layer. Figure 15 ? The vertical axis represents the energy of Ec (the bottom of the conduction band). In electron mobility, the graph of the conduction band is important. It is speculated that the conduction band bends near the barrier layer in the active layer, electrons are likely to accumulate, are easily affected by defects, and it is easy to cause a decrease in mobility.

[0186] Figure 16 (Comparative Example D) is an energy band diagram of a structure in which a 100 nm i-GaAs layer as an active layer and a 500 nm i-AlAs layer as a barrier layer are stacked on a 500 nm i-AlAs layer, with the vicinity of the active layer and the barrier layer magnified. Figure 16 The vertical axis represents the energy of Ec (the bottom of the conduction band). The conduction band diagram is important in electron mobility. Near the barrier layer in the active layer, no conduction band bending, as seen in electron accumulation, was observed. Here, in Example D and Comparative Example D, a material with a lattice constant close to that of the active layer and a larger band gap than the active layer was selected as the barrier layer.

[0187] The embodiments have been described above based on the accompanying drawings and examples. However, it should be noted that those skilled in the art can easily make various modifications and alterations based on this disclosure. Therefore, it should be understood that these modifications and alterations are included within the scope of this disclosure.

Claims

1. A semiconductor device, wherein, The semiconductor device includes an active layer and a barrier layer stacked on the active layer. The active layer contains arsenic or antimony. The barrier layer comprises aluminum. When the direction in which the barrier layer is stacked on the active layer is defined as the depth direction, in the atomic concentration distribution along the depth direction from the active layer to the barrier layer, the rising position of hydrogen concentration is closer to the center of the active layer than the rising position of aluminum concentration.

2. The semiconductor device according to claim 1, wherein, The active layer contains indium.

3. The semiconductor device according to claim 2, wherein, The active layer contains indium and antimony.

4. The semiconductor device according to claim 2, wherein, The active layer contains indium and arsenic.

5. The semiconductor device according to claim 1, wherein, The barrier layer contains antimony.

6. The semiconductor device according to claim 1, wherein, In the atomic concentration distribution along the depth direction from the active layer to the barrier layer, the hydrogen concentration becomes less than 50% of the concentration at the peak after reaching a peak.

7. The semiconductor device according to claim 6, wherein, In the atomic concentration distribution along the depth direction from the active layer to the barrier layer, the peak position of the hydrogen concentration is located within a range of less than 30 nm offset from the interface between the barrier layer and the active layer towards the active layer side.

8. The semiconductor device according to claim 6, wherein, In the atomic concentration distribution along the depth direction from the active layer to the barrier layer, the half-width of the peak hydrogen concentration is less than 60 nm.

9. The semiconductor device according to claim 1, wherein, In the atomic concentration distribution along the depth direction of the barrier layer, the hydrogen concentration at the other end is lower than that at the end adjacent to both the barrier layer and the active layer.

10. The semiconductor device according to claim 9, wherein, The barrier layer is doped with n-type or p-type atoms, and in the atomic concentration distribution along the depth direction of the barrier layer, when the hydrogen concentration distribution is approximated using a linear or quadratic function, the hydrogen concentration decreases monotonically from one end to the other end.

11. The semiconductor device according to claim 1, wherein, The barrier layer is doped into n-type or p-type.

12. The semiconductor device according to claim 1, wherein, The active layer and the barrier layer have different lattice constants in the unstrained state.

13. The semiconductor device according to claim 1, wherein, The active layer also contains aluminum.

14. A method for manufacturing a semiconductor device, comprising manufacturing the semiconductor device according to any one of claims 1 to 13, wherein, Before the barrier layer is formed into a film, a pressure rise annealing process is included, in which the pressure of the reaction chamber of the apparatus is increased to perform annealing.

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