Semiconductor device and method for manufacturing the same

Abstract

High performance semiconductor devices and methods for manufacturing semiconductor devices are provided. [Solution] The semiconductor device comprises an active layer and a barrier layer stacked on the active layer, the active layer containing arsenic or antimony, the barrier layer containing aluminum and also containing arsenic or antimony, and the direction in which the barrier layer is stacked on the active layer is the depth direction, and in the distribution of atomic concentration in the depth direction from the active layer to the barrier layer, the position where the hydrogen concentration rises is closer to the center of the active layer than the position where the aluminum concentration rises.

Description

[Technical Field]

[0001] The present 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, in realizing devices that use compound semiconductors containing InSb, it is preferable to use AlInSb as an electron barrier layer.

[0003] For example, Patent Document 1 discloses a compound semiconductor substrate including an AlInSb layer that has good crystallinity and excellent surface flatness and is manufactured using metal organic chemical vapor deposition (MOCVD). [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Publication No. 2018-104278 Summary of the Invention [Problem to be solved by the invention]

[0005] Here, semiconductor devices are used as, for example, IR light emitting devices or IR light receiving devices, and there is a demand for further improvement in emission intensity or detection sensitivity, i.e., a higher SNR (Signal to Noise Ratio) is required for practical use of semiconductor devices.

[0006] The present disclosure has been made in view of the above circumstances, and has an object to provide a high-performance semiconductor device and a method for manufacturing the semiconductor device. [Means for solving the problem]

[0007] (1) A semiconductor device according to an embodiment of the present disclosure includes: an active layer; a barrier layer laminated on the active layer, the active layer contains arsenic or antimony; the barrier layer contains aluminum and also contains arsenic or antimony; In the atomic concentration distribution in the depth direction from the active layer to the barrier layer, the position where the hydrogen concentration rises is closer to the center of the active layer than the position where the aluminum concentration rises, with the direction in which the barrier layer is stacked on the active layer being the depth direction.

[0008] (2) As one embodiment of the present disclosure, in (1), The active layer contains indium.

[0009] (3) As one embodiment of the present disclosure, in (2), The active layer includes indium and antimony.

[0010] (4) As an embodiment of the present disclosure, in (2), The active layer includes indium and arsenic.

[0011] (5) As an embodiment of the present disclosure, in any one of (1) to (4), The barrier layer contains antimony.

[0012] (6) As an embodiment of the present disclosure, in any one of (1) to (5), In the distribution of atomic concentration in the depth direction from the active layer to the barrier layer, the hydrogen concentration reaches a peak and then becomes 50% or less of the peak concentration.

[0013] (7) As an embodiment of the present disclosure, in any one of (1) to (6), In the distribution of atomic concentration in the depth direction from the active layer to the barrier layer, the position of the peak of hydrogen concentration is within a range of 30 nm or less from the interface between the barrier layer and the active layer toward the active layer.

[0014] (8) As an embodiment of the present disclosure, in any one of (1) to (7), In the atomic concentration distribution in the depth direction from the active layer to the barrier layer, the half-width of the hydrogen concentration peak is 60 nm or less.

[0015] (9) As an embodiment of the present disclosure, in any one of (1) to (8), In the distribution of atomic concentration in the depth direction in the barrier layer, the hydrogen concentration at one end where the barrier layer is adjacent to the active layer is lower than the hydrogen concentration at the other end.

[0016] (10) As an embodiment of the present disclosure, in (9), The barrier layer is doped, and in the distribution of atomic concentration in the depth direction of the barrier layer, the hydrogen concentration monotonically decreases from the one end to the other end.

[0017] (11) As an embodiment of the present disclosure, in any one of (1) to (10), The barrier layer is doped.

[0018] (12) As an embodiment of the present disclosure, in any one of (1) to (11), The active layer and the barrier layer have different lattice constants in an unstrained state.

[0019] (13) As an embodiment of the present disclosure, in any one of (1) to (12), The active layer further includes aluminum.

[0020] (14) A method for manufacturing a semiconductor device according to an embodiment of the present disclosure includes: A method for manufacturing a semiconductor device according to any one of (1) to (13), The method includes a pressure-rise annealing step of increasing the pressure in the reaction chamber of the device and performing annealing before depositing the barrier layer. [Effects of the Invention]

[0021] According to the present disclosure, a high-performance semiconductor device and a method for manufacturing the semiconductor device can be provided. [Brief explanation of the drawings]

[0022] [Figure 1] FIG. 1 is a diagram showing an example of distribution of aluminum concentration and hydrogen concentration in a semiconductor device according to an embodiment of the present disclosure. [Figure 2] FIG. 2 is a diagram showing the defect amount dependency of resistance when the semiconductor device is an infrared device. [Figure 3] FIG. 3 is a diagram showing a band diagram in the case where the semiconductor device is an infrared device. [Figure 4] FIG. 4 is a diagram showing the dependency of mobility on the defect amount when the semiconductor device is a Hall element. [Figure 5] FIG. 5 is a diagram showing a band diagram when the semiconductor device is a Hall element. [Figure 6] FIG. 6 is a diagram illustrating the structure of a semiconductor device and showing a schematic distribution of aluminum concentration and hydrogen concentration. [Figure 7] FIG. 7 is a diagram for explaining dangling bonds and termination by hydrogen. [Figure 8] FIG. 8 is a diagram showing a band diagram when the semiconductor device is a Hall element. [Figure 9] FIG. 9 is a diagram showing a band diagram of Example A. [Figure 10] FIG. 10 is a diagram showing a band diagram of Comparative Example A. [Figure 11] FIG. 11 is a diagram showing a band diagram of Example B. [Figure 12]FIG. 12 is a diagram showing a band diagram of Comparative Example B. [Figure 13] FIG. 13 is a diagram showing a band diagram of Example C. [Figure 14] FIG. 14 is a diagram showing a band diagram of Comparative Example C. [Figure 15] FIG. 15 is a diagram showing a band diagram of Example D. [Figure 16] FIG. 16 is a diagram showing a band diagram of Comparative Example D. DETAILED DESCRIPTION OF THE INVENTION

[0023] <Semiconductor devices> The semiconductor device according to this embodiment includes an active layer and a barrier layer stacked on the active layer. The left diagram in FIG. 6 illustrates the structure of a semiconductor device. The semiconductor device may include a substrate. The semiconductor device may also include a first layer disposed between the substrate and the active layer, and a second layer adjacent to the barrier layer on the opposite side of the active layer. At least one of the first layer and the second layer may be omitted as appropriate depending on the type of semiconductor device. The semiconductor device is configured by stacking layers including at least the active layer and the barrier layer. Hereinafter, the direction in which the barrier layer is stacked on the active layer will be referred to as the depth direction, and the positions of the components will be described.

[0024] Here, the semiconductor device may be an infrared device (IR device). The infrared device is an infrared light emitting element or an infrared light receiving element, and is a collective name for these. An infrared light emitting element is realized with the structure of the semiconductor device described below, and an infrared light receiving element is realized with the same structure. When the semiconductor device is an infrared light emitting element, it may specifically be a light emitting diode (LED). When the semiconductor device is an infrared light receiving element, it may specifically be a photodiode (PD). Furthermore, the semiconductor device may be a Hall element. A case where the semiconductor device is a Hall element will be described in one of the examples described below. In other descriptions of this embodiment, the semiconductor device will be described as an infrared device.

[0025] <Active layer> The active layer may be composed of arsenic (As) or antimony (Sb). Therefore, the material of the active layer may be, but is not limited to, InAs or InSb. The active layer may further contain aluminum (Al). Therefore, the material of the active layer may be, but is not limited to, InAlSb. The active layer may also contain atoms such as gallium (Ga) or may be composed of an alloy containing these. The active layer is not limited to the above materials, and other materials may also be used. From the viewpoint of device characteristics, the active layer is preferably single-crystal. Furthermore, when the active layer contains indium, electrons tend to accumulate at the interface between the active layer and the barrier layer due to band bending, and the effect of hydrogen termination, described below, is significant.

[0026] <Barrier layer> The barrier layer contains aluminum (Al) and 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 material, but are not limited to this. The barrier layer preferably forms an energy barrier against electrons or holes in the active layer. The barrier layer may also contain atoms such as gallium (Ga) or may be composed of an alloy containing these atoms. From the viewpoint of device characteristics, the barrier layer is preferably single crystalline. The lattice constant of the barrier layer material is preferably close to that of the active layer material. To form an energy barrier against electrons or holes without significantly changing the lattice constant of the active layer, it is preferable that the barrier layer material contains a material that is the active layer material plus aluminum. Furthermore, when the barrier layer contains antimony, electrons tend to accumulate at the interface between the active layer and the barrier layer due to band bending, which enhances the effect of hydrogen termination, as described below.

[0027] <Substrate> The substrate is not particularly limited as long as it can support layers including an active layer and a barrier layer, and examples thereof include GaAs substrates, InP substrates, GaN substrates, Si substrates, quartz substrates, aluminum substrates, oxide substrates, aluminum nitride substrates, and polyimide flexible substrates.

[0028] <First layer> The first layer may be, for example, a semiconductor layer of a first conductivity type. The first conductivity type may be, for example, n-type. The first layer may be made of, for example, InSb, GaAs, InAs, InGaAs, InAlSb, GaAsSb, or InGaP, but is not limited to these. It is also preferable that the first layer has a larger band gap than the active layer and forms an energy barrier against electrons or holes in the active layer.

[0029] <Second layer> The second layer may be, for example, a semiconductor layer of a second conductivity type. The second conductivity type may be a conductivity type different from the first conductivity type, for example, p-type. As another example, the first conductivity type may be p-type and the second conductivity type may be n-type. Examples of materials that may be used for the second layer include, but are not limited to, InSb, GaAs, InAs, InGaAs, InAlSb, GaAsSb, and InGaP.

[0030] <Hydrogen concentration distribution> As described above, semiconductor devices are required to have a higher SNR. The inventors have conducted extensive research into ways to provide high-performance semiconductor devices and have found that performance can be improved by appropriately terminating dangling bonds.

[0031] FIG. 7 is a diagram illustrating dangling bonds and termination by hydrogen. The central diagram in FIG. 7 is a semiconductor device, which is the same as FIG. 6. The active layer and the barrier layer have different lattice constants in an unstrained state (left diagram in FIG. 7). Therefore, dangling bonds are likely to occur at the boundary between the active layer and the barrier layer due to the difference in lattice constants (the number of defects is likely to increase). Here, hydrogen can terminate dangling bonds (right diagram in FIG. 7). In other words, hydrogen can reduce dangling bonds and defect levels. The barrier layer may contain hydrogen (H), and the distribution of hydrogen concentration can be adjusted by adjusting the process of the semiconductor device manufacturing method. The semiconductor device according to this embodiment can achieve a high SNR because hydrogen terminates defects near the interface between the barrier layer and the active layer and reduces defect levels.

[0032] FIG. 1 shows an example of the distribution of aluminum concentration and hydrogen concentration in a semiconductor device according to this embodiment. The measurement was carried out using a SIMS (Secondary Ionization Mass Spectrometer). Specifically, a sector-type SIMS device, "IMS-7f" manufactured by CAMECA, was used. The ion species of the primary ion beam was Cs +The acceleration voltage of the primary ion beam was 15 kV. The polarity of the secondary ion detection was negative. The horizontal axis in Figure 1 represents "depth," which is the distance in the depth direction from the surface of the semiconductor device, with the surface of the semiconductor device (the surface furthest from the substrate in the layer furthest from the substrate) set at zero, as shown in Figure 6. The vertical axis represents normalized concentration. The aluminum concentration was normalized by dividing by the peak (maximum) of the aluminum concentration. Similarly, the hydrogen concentration was normalized by dividing by the peak (maximum) of the hydrogen concentration. As shown in Figure 1, the hydrogen concentration peak is shifted from the aluminum concentration peak and can be said to be shifted toward the active layer (center). The appropriate distribution of atomic concentration in the depth direction from the active layer to the barrier layer of a semiconductor device is described below.

[0033] First, localization of hydrogen atoms is preferable for efficient termination of defect levels and because hydrogen atoms can deactivate dopants. In particular, when semiconductor devices are infrared devices, the barrier layer may be doped. If hydrogen atoms deactivate the dopants in the barrier layer, parasitic resistance may increase. Therefore, by limiting the range of hydrogen atoms present in the barrier layer, high-performance devices with low parasitic resistance and capable of terminating interface defects can be realized. Specifically, it is important that hydrogen atoms are distributed in large numbers in the region adjacent to the active layer and the barrier layer. Here, carriers are likely to accumulate due to band bending (conduction band, valence band) not only at the interface between the active layer and the barrier layer but also in the region of the active layer adjacent to the barrier layer (approximately several tens of nanometers). Therefore, a configuration that increases the hydrogen concentration not only at the interface but also in the region of the active layer adjacent to the barrier layer is preferable.

[0034] Here, Fig. 6 illustrates the structure of a semiconductor device and shows a schematic distribution of aluminum concentration and hydrogen concentration. The schematic distribution is obtained by approximating the detailed distribution shown in Fig. 1 using a Gaussian function. The rising position is the inflection point in the approximated Gaussian function that reaches a peak from the active layer toward the barrier layer (in the reverse direction of depth).

[0035] In approximating the concentration distribution, in addition to a Gaussian function, the tailing seen in SIMS measurements may be approximated using exponential terms. Tailing is the spread of apparent concentration caused by artifacts associated with sputtering or the secondary ion generation process. It is known that when SIMS measurements are performed in the depth direction, the signal has a base in the depth direction. Even when tailing is approximated using exponential terms, the rising position is represented by the inflection point in the Gaussian function component. When SIMS measurements are performed in the depth direction, the signal can be approximated using the following equations (1) to (3).

[0036]

number

[0037] Here, z is the coordinate in the depth direction. meas is the atomic concentration measured by SIMS analysis. gaus is a Gaussian function that indicates the atomic concentration. tail is a function that indicates the influence of tailing. z1 is a parameter that indicates the peak center of the Gaussian function. σ is a parameter that indicates the spread of the Gaussian function. z2 is a parameter that indicates the coordinate where tailing begins to occur. λ is a parameter that indicates the degree of spread of the tailing. A1 and A2 are coefficients.

[0038] In addition, to smoothly express the area around the coordinate where tailing begins to occur, the tailing can be approximated using a smoothed switching function S as in equations (4) and (5) instead of equation (3). In this case, the rising position is also expressed as the inflection point in the components of the Gaussian function. Here, α in equation (5) is a parameter indicating the degree of smoothness.

[0039]

number

[0040] Furthermore, if the distribution does not have a clear peak shape, approximation may be performed using only a portion of the distribution. For example, when the barrier layer has a certain thickness or more, the aluminum concentration increases in the region corresponding to the interface from the active layer toward the barrier layer (in the reverse direction of the depth), and then continues to maintain a value above a certain level in the region corresponding to the barrier layer. This aluminum concentration distribution may be approximated using a Gaussian function using only the portion that increases in the region corresponding to the interface.

[0041] In the semiconductor device according to this embodiment, in the distribution of atomic concentrations in the depth direction from the active layer to the barrier layer, the rising position of the hydrogen concentration is closer to the active layer than the rising position of the aluminum concentration. Here, "close to the active layer" may mean "close to the center of the active layer." Also, "close to the active layer" may mean "close to the first layer" or "close to the substrate." When the semiconductor device has such a distribution of hydrogen and aluminum, hydrogen atoms terminate defects and reduce defect levels, thereby achieving a high SNR.

[0042] Furthermore, from the viewpoint of localizing hydrogen atoms, in the distribution of atomic concentration in the depth direction from the active layer to the barrier layer, after the hydrogen concentration peaks, it is preferable that the hydrogen concentration becomes 70% or less of the peak concentration, and more preferably 50% or less.

[0043] In addition, in the distribution of atomic concentration in the depth direction from the active layer to the barrier layer, the position of the peak of hydrogen concentration is preferably the interface between the barrier layer and the active layer. However, the position of the peak of hydrogen concentration may be within a range of 30 nm or less from the interface toward the active layer. Here, the interface between the barrier layer and the active layer can be defined by a plane corresponding to the rising position of atoms (e.g., aluminum) contained in the barrier layer.

[0044] In order to localize hydrogen atoms, the half-width of the hydrogen concentration peak in the depth direction distribution from the active layer to the barrier layer is preferably 60 nm or less. In order to efficiently terminate defects by hydrogen, the half-width of the hydrogen concentration peak is preferably 1 nm or more.

[0045] Furthermore, from the viewpoint of localizing hydrogen atoms, it is preferable that the hydrogen concentration in the barrier layer is low. Therefore, it is preferable that the hydrogen concentration at one end of the barrier layer adjacent to the active layer is lower than the hydrogen concentration at the other end in the depth direction of the barrier layer. Furthermore, it is more preferable that the barrier layer is doped, and that the hydrogen concentration at the depth direction of the barrier layer monotonically decreases from one end to the other end. Here, "monotonically decreasing" refers to a monotonically decreasing state when the detailed distribution is approximated by a linear or quadratic function.

[0046] When the barrier layer is used as an electron blocking layer, it is preferably p-doped. When the barrier layer is used as a hole blocking layer, it is preferably n-doped. However, when the barrier layer is doped, it is preferable that the hydrogen concentration in the barrier layer is low in order to prevent inactivation of the dopant.

[0047] <Semiconductor device manufacturing method> The inventors have found that a semiconductor device having the above-described hydrogen concentration distribution can be manufactured based on the manufacturing method of Patent Document 1 by performing a pressure-rise annealing step in which the pressure in the reaction chamber of the device is increased and annealed before forming the barrier layer. An example of a process for manufacturing a semiconductor device according to this embodiment is described below. The above-described semiconductor device can also be manufactured by increasing the hydrogen flow rate based on the manufacturing method of Patent Document 1 to localize hydrogen atoms.

[0048] The stacked film was fabricated using MOCVD as follows. First, a zinc-blende semi-insulating GaAs substrate was prepared. Trimethylindium (TMIn) as the In source, trisdimethylaminoantimony (TDMASb) as the Sb source, and dimethyltellurium (DMTe) as the n-dopant were supplied to the semi-insulating GaAs substrate at a substrate temperature of 500°C to form an n-InSb layer. At this time, the V / III ratio, which is the ratio of the supply amount of group V elements to the supply amount of group III elements, was 5.0. The thickness of the n-InSb layer was 1000 nm. The doping concentration was 1.0 x 10 19 / cm 3 It was.

[0049] Next, at a substrate temperature of 500°C, trimethylindium (TMIn) was supplied as the In source, trisdimethylaminoantimony (TDMASb) as the Sb source, and dimethylzinc (DMZn) as the p-dopant, to form a p-InSb layer. The V / III ratio was 5.0. The p-InSb layer corresponds to the active layer. The thickness of the p-InSb layer was 2000 nm. The doping concentration was 6.0×10 16 / cm 3 It was.

[0050] The supply of each source gas was stopped, and with only hydrogen flowing into the reactor, the pressure in the reactor was increased from 50 torr to 300 torr. Annealing was performed under this condition for 10 minutes. After that, the pressure in the reactor was reduced from 300 torr to 50 torr.

[0051] Next, at a substrate temperature of 500°C, tritertiarybutylaluminum (TTBAl) was supplied as an Al source, trimethylindium (TMIn) as an In source, and trisdimethylaminoantimony (TDMASb) as an Sb source. Dimethylzinc (DMZn) was then supplied as a p-dopant to form a p-AlInSb layer. The p-AlInSb layer corresponds to the barrier layer. At this time, the Al source, In source, and Sb source were all supplied so that the Al / (Al+In) source ratio was 0.50. Then, Al 0.7 In0.3 The Al / (Al+In) ratio was increased to 0.70 (i.e., the supply rate of the Al source was increased) so that Sb was formed. At this time, the V / III ratio was 5.0. The thickness of the p-AlInSb layer was 40 nm. The doping concentration was 2.0 × 10 18 / cm 3 It was.

[0052] Next, at a substrate temperature of 500°C, trimethylindium (TMIn) was supplied as an In source, trisdimethylaminoantimony (TDMASb) as an Sb source, and dimethylzinc (DMZn) as a p-dopant, to form a p-InSb layer. The V / III ratio was 5.0. The thickness of the p-InSb layer was 250 nm. The doping concentration was 2.0×10 18 / cm 3 It was.

[0053] <Raw materials> In the above manufacturing method, the In source, Sb source, and Al source are not particularly limited as long as they can form an InSb layer and an AlInSb layer. Examples of In sources include trimethylindium (TMIn) and triethylindium (TEIn). Examples of Sb sources include trimethylantimony (TMSb), triethylantimony (TESb), trisdimethylaminoantimony (TDMASb), and triisopropylantimony (TIPSb). Examples of Al sources include trimethylaminealane (TMAAl), triisobutylaluminum (TIBAl), and dimethylaluminum hydride (DMAH). Examples of Al sources include dimethylethylaminealane (DMEAAl) and tritertiarybutylaluminum (TTBAl).

[0054] From the viewpoint of the source decomposition temperature, the In source is preferably trimethylindium (TMIn), triethylindium (TEIn), or a combination thereof. From the viewpoint of the long-term stability of the source, the Al source is preferably tritertiarybutylaluminum (TTBAl). From the viewpoint of suppressing carbon impurities, the Sb source is preferably trisdimethylaminoantimony (TDMASb).

[0055] In addition to the above raw materials, a dopant may be supplied to control the conductivity type. Examples of the dopant include dimethyl zinc (DMZn), diethyl zinc (DEZn), dimethyl tellurium (DMTe), diethyl tellurium (DETe), tetramethyl tin (TMSn), and tetraethyl tin (TESn).

[0056] Example 1 The resistance of the IR sensor (IR receiving device) was calculated for the following two laminated film structures (a) and (b). The resistance of the IR sensor (without bias voltage applied) is an important indicator that determines thermal noise, and a large resistance is preferable. The manufacturing method for the laminated film follows the steps described above.

[0057] The stacked film structures (a) and (b) have an active layer and a barrier layer stacked on an n-InSb layer (corresponding to the first layer in Figure 6), and a p-InSb layer (corresponding to the second layer in Figure 6) stacked on the barrier layer.

[0058] In the laminated film structure (a), the thickness of the n-InSb layer is 1000 nm and the doping concentration is 1.0 × 10 19 / cm 3 The thickness of the p-InSb active layer is 2000 nm, and the doping concentration is 6.0 × 10 16 / cm 3 The barrier layer is p-Al 0.18 In 0.82 The thickness of the Sb layer is 20 nm, and the doping concentration is 2.0 × 10 18 / cm 3 The thickness of the p-InSb layer is 500 nm, and the doping concentration is 2.0 × 10 18 / cm3 is.

[0059] In the laminated film structure (b), the thickness of the n-InSb layer is 1000 nm and the doping concentration is 1.0 × 10 19 / cm 3 The active layer is non-doped i-Al 0.09 In 0.91 The thickness of the Sb layer is 2000 nm. 0.27 In 0.73 The thickness of the Sb layer is 20 nm, and the doping concentration is 2.0 × 10 18 / cm 3 The thickness of the p-InSb layer is 500 nm, and the doping concentration is 2.0 × 10 18 / cm 3 The height of the energy barrier of the barrier layer against the active layer, which affects the resistance described below, is the same in the laminated film structure (a) and the laminated film structure (b).

[0060] Figure 2 shows the defect-dependence of resistance for stacked film structures (a) and (b). The defect amount in the region (30 nm) near the barrier layer of the active layer was changed, and the resistance was calculated. The resistance here is the resistance to the current flowing vertically through the stacked film structure. The resistance on the vertical axis of Figure 2 is normalized to 1 for stacked film structures (a) and (b), respectively, when the defect amount is 0.01. As shown in Figure 2, the resistance value improves by reducing the defect amount near the barrier layer of the active layer. This effect is more pronounced for stacked film structure (b), i.e., when the active layer contains Al.

[0061] Figure 3 is a band diagram of the stacked film structure (a), showing an enlarged view of the vicinity of the active layer and barrier layer. The vertical axis of Figure 3 represents the energy of Ec (bottom of the conduction band) and Ev (top of the valence band). The horizontal coordinate of Figure 3 represents the position in the depth direction. In IR devices, the recombination current in the active layer is an important factor in determining the resistance value. In the active layer, the valence band bends approximately 30 nm (indicated by the arrow) near the barrier layer. From this, it is estimated that holes tend to accumulate in this region, and that the recombination current is likely to cause a decrease in resistance value.

[0062] <Example 2> The electron mobility in the lateral direction (the direction perpendicular to the depth direction) was calculated for the following laminated film structure. Here, mobility is an important index that determines the SNR of the Hall element, and a large mobility is preferable. The laminated film was manufactured according to the above steps.

[0063] The laminated film structure of this example is i-Al 0.1 In 0.9 The active layer and barrier layer are stacked on top of the Sb layer (corresponding to the first layer in Figure 6). 0.1 In 0.9 The thickness of the Sb layer is 100 nm, and the mobility is 3000 cm 2 / Vs. The thickness of the i-InSb active layer is 100 nm, and the mobility is 52000 cm 2 / Vs. The barrier layer is i-Al 0.1 In 0.9 The thickness of the Sb layer is 100 nm, and the mobility is 3000 cm 2 / Vs.

[0064] Figure 4 shows the defect density dependency of mobility for a stacked film structure. The mobility here refers to the mobility for current flowing laterally through the stacked film structure. The mobility was calculated by changing the defect density in the region of the active layer near the barrier layer (30 nm, as in Figure 3). As shown in Figure 4, the mobility of the stacked film is improved by reducing the defect density near the barrier layer of the active layer.

[0065] Further, FIG. 8 is a band diagram of the laminated film structure of this embodiment, which is an enlarged view of the vicinity of the active layer and the barrier layer. The vertical axis in FIG. 8 indicates the energy of Ec (the bottom of the conduction band). In terms of electron mobility, the conduction band diagram is important. The horizontal axis coordinates in FIG. 8 indicate the position in the depth direction. In the active layer, the conduction band is bent in the vicinity of the barrier layer, and it is estimated that electrons tend to accumulate, are easily affected by defects, and easily cause a decrease in mobility. Further, FIG. 5 is a band diagram of a configuration in which the film thickness of the i-InSb layer of the active layer in Example 2 is 300 nm. In the active layer, the conduction band is bent at about 60 nm (arrow part) in the vicinity of the barrier layer. From this, it is estimated that in this region, electrons tend to accumulate and easily cause a decrease in mobility.

[0066] Here, particularly when the barrier layer contains Sb, in the region near the barrier layer in the active layer, due to the bending of the conduction band, electrons tend to accumulate and easily cause a decrease in mobility. Therefore, it is estimated that the effect of hydrogen termination is large. The reason will be described below.

[0067] <Active layer of InAs> FIG. 9 (Example A) is a band diagram of a structure in which a 100-nm-thick i-InAs layer as an active layer and a 500-nm-thick i-AlSb layer as a barrier layer are laminated on a 500-nm-thick i-AlSb layer, and is an enlarged view of the vicinity of the active layer and the barrier layer. The vertical axis in FIG. 9 indicates the energy of Ec (the bottom of the conduction band). In terms of electron mobility, the conduction band diagram is important. In the active layer, the conduction band is bent in the vicinity of the barrier layer, and it is estimated that electrons tend to accumulate, are easily affected by defects, and easily cause a decrease in mobility.

[0068] FIG. 10 (Comparative Example A) is i-Al 0.2 In 0.8 On a 500-nm-thick As layer, a 100-nm-thick i-InAs layer as an active layer and a i-Al 0.2 In 0.8It is a band diagram of a structure with a 500-nm-thick As layer laminated, and the vicinity of the active layer and the barrier layer is enlarged. The vertical axis in FIG. 10 indicates the energy of Ec (the bottom of the conduction band). In terms of electron mobility, the diagram of the conduction band is important. In the active layer, no bending of the conduction band that accumulates electrons is observed in the vicinity of the barrier layer.

[0069] <Active layer of InSb> FIG. 11 (Example B) shows an i-Al 0.2 In 0.8 On a 500-nm-thick Sb layer, a 100-nm-thick i-InSb layer as an active layer and an i-Al 0.2 In 0.8 It is a band diagram of a structure with a 500-nm-thick Sb layer laminated, and the vicinity of the active layer and the barrier layer is enlarged. The vertical axis in FIG. 11 indicates the energy of Ec (the bottom of the conduction band). In terms of electron mobility, the diagram of the conduction band is important. In the active layer, the conduction band is bent in the vicinity of the barrier layer, and it is estimated that electrons are likely to accumulate, are likely to be affected by defects, and are likely to cause a decrease in mobility.

[0070] FIG. 12 (Comparative Example B) shows an i-Al 0.2 In 0.8 On a 500-nm-thick As layer, a 100-nm-thick i-InSb layer as an active layer and an i-Al 0.2 In 0.8 It is a band diagram of a structure with a 500-nm-thick As layer laminated, and the vicinity of the active layer and the barrier layer is enlarged. The vertical axis in FIG. 12 indicates the energy of Ec (the bottom of the conduction band). In terms of electron mobility, the diagram of the conduction band is important. In the active layer, no bending of the conduction band that accumulates electrons is observed in the vicinity of the barrier layer. <​​​​​​​FIG. 13 (Example C) shows i-Al 0.2 In 0.8 On a 500 nm-thick i-InSb layer, a 100 nm-thick i-InSb layer as an active layer and a 500 nm-thick i-Al 0.2 In 0.8 Sb layer are stacked, and it is a band diagram of the structure, with the vicinity of the active layer and the barrier layer enlarged. The vertical axis in FIG. 13 indicates the energy of Ec (the bottom of the conduction band). In terms of electron mobility, the diagram of the conduction band is important. In the active layer, the conduction band is bent in the vicinity of the barrier layer, and it is estimated that electrons are likely to accumulate, are likely to be affected by defects, and are likely to cause a decrease in mobility.

[0073] FIG. 14 (Comparative Example C) is a band diagram of a structure in which a 100 nm-thick i-GaSb layer as an active layer and a 500 nm-thick i-AlSb layer as a barrier layer are stacked on a 500 nm-thick i-AlSb layer, with the vicinity of the active layer and the barrier layer enlarged. The vertical axis in FIG. 14 indicates the energy of Ec (the bottom of the conduction band). In terms of electron mobility, the diagram of the conduction band is important. In the active layer, no bending of the conduction band that accumulates electrons is observed in the vicinity of the barrier layer. Here, in Example C and Comparative Example C, a material having a lattice constant relatively close to that of the active layer and a larger band gap than the active layer is selected as the barrier layer.

[0074] <As-based active layer> FIG. 15 (Example D) is a band diagram of a structure in which a 100 nm-thick i-InAs layer as an active layer and a 500 nm-thick i-AlSb layer as a barrier layer are stacked on a 500 nm-thick i-AlSb layer, with the vicinity of the active layer and the barrier layer enlarged. The vertical axis in FIG. 15 indicates the energy of Ec (the bottom of the conduction band). In terms of electron mobility, the diagram of the conduction band is important. In the active layer, the conduction band is bent in the vicinity of the barrier layer, and it is estimated that electrons are likely to accumulate, are likely to be affected by defects, and are likely to cause a decrease in mobility.

[0075] Figure 16 (Comparative Example D) is a band diagram of a structure in which a 100-nm i-GaAs active layer and a 500-nm i-AlAs barrier layer are stacked on a 500-nm i-AlAs layer, and shows an enlarged view of the active layer and the barrier layer. The vertical axis of Figure 16 represents the energy Ec (bottom of the conduction band). The conduction band diagram is important for electron mobility. No conduction band bending that would accumulate electrons is observed near the barrier layer in the active layer. Here, in Example D and Comparative Example D, a material with a lattice constant relatively close to that of the active layer and a band gap larger than that of the active layer is selected for the barrier layer.

[0076] Although the embodiments have been described above based on the drawings and examples, it should be noted that those skilled in the art can easily make various modifications and alterations based on the present disclosure. Therefore, it should be noted that these modifications and alterations are included in the scope of the present disclosure.

Claims

1. an active layer; a barrier layer laminated on the active layer, the active layer contains arsenic or antimony; the barrier layer contains aluminum and also contains arsenic or antimony; a semiconductor device, wherein in a distribution of atomic concentrations in a depth direction from the active layer to the barrier layer, the position where a hydrogen concentration rises is closer to a center of the active layer than the position where an aluminum concentration rises, where the direction in which the barrier layer is stacked on the active layer is defined as a depth direction.

2. The semiconductor device of claim 1 , wherein the active layer comprises indium.

3. The semiconductor device of claim 2 , wherein the active layer comprises indium and antimony.

4. The semiconductor device of claim 2 , wherein the active layer comprises indium and arsenic.

5. The semiconductor device of claim 1 , wherein the barrier layer comprises antimony.

6. 2. The semiconductor device according to claim 1, wherein in the distribution of atomic concentration in the depth direction from the active layer to the barrier layer, the hydrogen concentration reaches a peak and then becomes 50% or less of the peak concentration.

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

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

9. 2. The semiconductor device according to claim 1, wherein the hydrogen concentration at one end of the barrier layer adjacent to the active layer is lower than the hydrogen concentration at the other end of the barrier layer in the depth direction of the barrier layer.

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

11. 10. The semiconductor device of claim 1, wherein the barrier layer is doped 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 an unstrained state.

13. The semiconductor device of claim 1 , wherein the active layer further comprises aluminum.

14. A method for manufacturing a semiconductor device according to any one of claims 1 to 13, comprising the steps of: A method for manufacturing a semiconductor device, comprising a pressure-rise annealing step of increasing the pressure in a reaction chamber of the device and performing annealing before depositing the barrier layer.

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