A staggered floating island device and its rapid opening structure and self-alignment manufacturing method

Abstract

The present invention relates to a staggered floating island device and a fast turn-on structure and a self-aligned manufacturing method in the field of semiconductor technology. The staggered floating island device includes a surface layer, a bottom layer and a drift region. The drift region includes a plurality of epitaxial layers and a plurality of floating island layers. The floating island layers are staggered. The floating islands in the floating island layers are composed of two doping regions. The floating islands of at least two groups of floating island layers partially overlap or do not overlap in the top view direction. A group of floating island layers is arranged between each two groups of epitaxial layers, or a group of epitaxial layers is arranged between each two groups of floating island layers. A heavily doped inversion region is arranged in the floating island layer of the fast turn-on structure. The use of two doping regions in the floating island is conducive to making the doping concentration of the floating island close to an ideal uniform distribution after annealing, and is conducive to increasing the junction capacitance of the floating island and reducing the turn-on voltage. The staggered floating islands have the advantage of reducing the hindrance of space charge to the current after multiple turns-ons, and alleviate the problem of reduced conduction capacity of the floating island device after multiple turns-ons.

Description

Technical Field

[0001] The invention relates to the field of semiconductor technology, and in particular to a staggered floating island device and a rapid opening structure and a self-alignment manufacturing method thereof. Background Art

[0002] In recent years, the world has attached increasing importance to energy conservation and emission reduction, which has put forward higher requirements for loss control and efficiency improvement of large-scale power electronic equipment. As an important component of power electronic equipment, semiconductor power devices have received extensive attention in the industry.

[0003] Breakdown voltage is an important indicator of semiconductor power devices, indicating the maximum voltage that the device can withstand. A floating island device (or floating junction device) refers to a special power device in which there is a region in its drift region that is not directly connected to the electrode and has an opposite doping type to the drift region. At the moment when the floating island device with N-type doping in the drift region changes from a blocking state to a conducting state, since the P-type doping region inside the drift region is not directly connected to the electrode, the hole carriers cannot enter the P-type doping region, resulting in negative charges remaining in the P-type doping region. At the same time, a large number of positive charges are attracted to the N-type drift region, filling the drift region in the form of space charges, causing energy band bending, thereby hindering the flow of electron carriers. That is, a floating island device with a floating doping region in the drift region cannot complete conduction recovery under low voltage. In this case, only when the bias voltage is large enough can the charge conduct through the drift region, but when the bias voltage is low, there is a problem of being unable to restore the conduction capability.

[0004] Adding a heavily doped inversion region to the floating island can inject electrons into the drift region at the time of conduction recovery, neutralize the positive space charge in the drift region, reduce the potential barrier in the drift region, and eliminate the current obstruction at the time of opening. However, after the floating island device with a heavily doped inversion region added to the floating island is turned on many times, the heavily doped inversion region in the floating island will accumulate positive space charge, generate a space electric field, and form a potential barrier at the floating island. This will cause the drift region around the floating island to also have a space charge region, which will hinder the flow of electrons when the floating island device is turned on. Therefore, the resistance of the floating island device will increase significantly after multiple openings. Summary of the invention

[0005] In view of the shortcomings of the prior art, the present invention provides a staggered floating island device and a manufacturing method, which has the advantage of eliminating current obstruction after multiple openings and breaks through the bottleneck of obvious decrease in conductivity after multiple openings.

[0006] In order to solve the above technical problems, the present invention is solved by the following technical solutions:

[0007] According to an embodiment of the present invention, an interlaced floating island device comprises a surface layer, a bottom layer and a drift region, wherein the drift region comprises a plurality of groups of epitaxial layers and a plurality of groups of floating island layers, a group of floating island layers is arranged between every two groups of epitaxial layers, or a group of epitaxial layers is arranged between every two groups of floating island layers, the surface layer and the bottom layer are located at both ends of the drift region, wherein there are at least two floating island layers, wherein at least two groups of floating island layers are provided with a first doping region and a second doping region, wherein the second doping region is distributed on the upper part of the first doping region, the doping concentration of the second doping region is higher than that of the first doping region, the first doping region and the second doping region are opposite to the doping type of the epitaxial layer, wherein the first doping region and the second doping region of at least one group of floating island layers and the first doping region and the second doping region of another group of floating island layers are at different positions in the horizontal direction, that is, the first doping region and the second doping region of at least one group of floating island layers and the first doping region and the second doping region of another group of floating island layers partially overlap or have no overlap in the top view direction.

[0008] Optionally, the floating island layer and the epitaxial layer are combined in a staggered upward arrangement, and the floating island device includes two groups of floating island layers and three groups of epitaxial layers, the floating island layer is sandwiched between the two groups of epitaxial layers, and the two groups of floating island layers are staggered.

[0009] Optionally, the epitaxial layer may be doped with a concentration of ~ semiconductor materials.

[0010] Optionally, the first doping regions and the second doping regions of at least two groups of the floating island layers partially overlap or do not overlap in the horizontal direction.

[0011] Optionally, the floating island layer is provided with a first doping region, a second doping region and a third doping region, the first doping region and the second doping region have opposite doping types to the epitaxial layer, and the doping type of the third doping region is the same as the doping type of the epitaxial layer.

[0012] Optionally, the floating island layer further includes a fourth doping region, and the fourth doping region has the same doping type as the epitaxial layer.

[0013] Optionally, the fourth doping region is distributed in the second doping region or part of the fourth doping region is distributed in the second doping region.

[0014] Optionally, a lower edge of the fourth doping region is not lower than a lower edge of the second doping region, and an upper edge of the fourth doping region is in direct contact with the epitaxial layer.

[0015] Optionally, a length of the fourth doping region distributed in the second doping region is shorter than a length of the second doping region.

[0016] Optionally, the fourth doping region may have a variety of design schemes and a variety of shapes.

[0017] Optionally, the top view of the fourth doping region may have a variety of design schemes, and the top view shape may have a variety of changes.

[0018] Optionally, the floating island layer includes a plurality of fourth doped regions arranged at intervals.

[0019] Optionally, the total length of the plurality of spaced-apart fourth doping regions is smaller than the length of the second doping region.

[0020] Optionally, when the staggered floating island device is a staggered floating island Schottky diode, the surface layer includes anode metal, and the bottom layer includes cathode drain metal; when the staggered floating island device is a fast-turn-on staggered floating island PN diode, the surface layer includes anode metal and an anode doping region, the doping type of the anode doping region is opposite to that of the epitaxial layer, and the bottom layer includes cathode drain metal; and when the staggered floating island device is a fast-turn-on staggered floating island junction barrier Schottky diode, the surface layer includes anode metal, an anode doping region and an anode epitaxial region, the doping type of the anode doping region is opposite to that of the epitaxial layer, the doping type of the anode epitaxial region is the same as that of the epitaxial layer, and the bottom layer includes cathode drain metal.

[0021] Optionally, when the staggered floating island device is a staggered floating island junction barrier Schottky diode, the surface layer further includes a third doped region.

[0022] Optionally, when the staggered floating island device is a fast-turned staggered floating island MOSFET, the surface layer includes source metal, channel well doping region, source doping region, gate oxide layer and gate metal, and the bottom layer includes cathode drain metal; when the staggered floating island device is a fast-turned staggered floating island IGBT, the surface layer includes source metal, channel well doping region, source doping region, gate oxide layer and gate metal, and the bottom layer includes cathode drain metal and drain doping region.

[0023] Optionally, the drift zone includes two or more groups of floating island layers, and the structure of each group of floating island layers is the same or different.

[0024] Optionally, in the three-dimensional structure, the first doping region, the second doping region, the third doping region and the fourth doping region extend to the entire cell in the third dimension; or the first doping region, the second doping region and the third doping region extend to the entire cell in the third dimension, while the fourth doping region only partially extends in the third dimension; or the third doping region extends to the entire cell in the third dimension, while the fourth doping region and the first doping region and the second doping region only partially extend in the third dimension.

[0025] Optionally, an upper edge of the fourth doping region is higher than, equal to, or lower than an upper edge of the second doping region.

[0026] According to another embodiment of the present invention, a fast-opening staggered floating island device comprises a surface layer, a bottom layer and a drift region, wherein the drift region comprises a plurality of epitaxial layers and a plurality of floating island layers, a group of floating island layers is arranged between every two groups of epitaxial layers, or a group of epitaxial layers is arranged between every two groups of floating island layers, the surface layer and the bottom layer are located at both ends of the drift region, wherein two or more groups of floating island layers are provided with a first doping region, a second doping region and a fourth doping region, wherein the second doping region is distributed on the upper part of the first doping region, and the doping concentration of the second doping region is higher than that of the first doping region, wherein the first doping region, the second doping region, the fourth doping region and the other group of floating island layers of at least one group of floating island layers are provided with a first doping region, a second doping region and a fourth doping region, wherein the first doping region, the second doping region, the fourth doping region and the other group of floating island layers of at least one group of floating island layers are provided with a second doping region, and the second doping region is provided with ... fourth doping region of at least one group of floating island layers are provided with a second doping region The first doping region, the second doping region, and the fourth doping region of the island layer are at different positions in the horizontal direction, that is, the first doping region, the second doping region, and the fourth doping region of at least one group of floating island layers and the first doping region, the second doping region, and the fourth doping region of another group of floating island layers partially overlap or have no overlap in the top view, the fourth doping region is in contact with the upper edge of the second doping region, the first doping region and the second doping region have opposite doping types to the epitaxial layer, the doping type of the fourth doping region is the same as the doping type of the epitaxial layer, the doping concentration of the fourth doping region is higher than the doping concentration of the epitaxial layer, and the upper edge of the fourth doping region is directly in contact with the epitaxial layer.

[0027] According to another embodiment of the present invention, a method for manufacturing a staggered floating island device is provided. The method is used to manufacture any of the staggered floating island devices described above.

[0028] According to another embodiment of the present invention, a method for manufacturing a self-aligned floating island device for rapid opening is provided. The method is used to manufacture any one of the aforementioned staggered floating island devices for rapid opening.

[0029] According to another embodiment of the present invention, a method for manufacturing an interlaced floating island Schottky diode includes the following steps: growing an N-type epitaxial layer on an N-type substrate layer; forming a floating island layer in the N-type epitaxial layer by photolithography and P-type ion implantation, the floating island layer including a first doping region, a second doping region, and a third doping region, the first doping region and the second doping region having opposite doping types to the epitaxial layer, and the third doping region having the same doping type as the epitaxial layer; repeatedly stacking N-type epitaxial layers and forming floating island layers; wherein at least two groups of floating island layers are interlaced; forming a surface layer and a bottom layer at both ends of a drift region by metal sputtering or metal evaporation, and then forming an ohmic contact between the bottom layer and the N-type epitaxial layer by high temperature annealing.

[0030] According to another embodiment of the present invention, a method for manufacturing a self-aligned floating island Schottky diode for rapid opening includes the following steps: growing an N-type epitaxial layer on an N-type substrate layer; forming a floating island layer in the N-type epitaxial layer by photolithography, P-type ion implantation, etching back after forming an oxide layer, and N-type ion implantation; the floating island layer includes a first doping region, a second doping region, a third doping region, and a fourth doping region, the fourth doping region is distributed in the second doping region or part of the fourth doping region is distributed in the second doping region, the first doping region and the second doping region are opposite to the doping type of the epitaxial layer, the doping type of the third doping region is the same as the doping type of the epitaxial layer, and the fourth doping region is the same as the doping type of the epitaxial layer; repeatedly stacking N-type epitaxial layers and forming a floating island layer; forming a surface layer and a bottom layer at both ends of a drift region by metal sputtering or metal evaporation, and then by high temperature annealing, an ohmic contact is formed between the bottom layer and the N-type epitaxial layer, and a Schottky contact is formed between the surface layer and the N-type epitaxial layer.

[0031] Compared with the prior art, the technical solution provided by the present invention has the following beneficial effects:

[0032] By introducing the second doping region, the floating island device actually manufactured can be closer to the ideal expected situation. In the actual manufacturing process, the doping region needs to undergo an annealing process after ion implantation. Since the injected impurities will diffuse at high temperatures, if there is only the first doping region, after high-temperature diffusion, the doping concentration in the center of the floating island will be high and the doping concentration at the edge of the floating island will become low. Introducing a second doping region with a higher concentration on the top of the first doping region can diffuse more impurities outward at high temperatures, increase the doping concentration at the edge of the floating island, and make the overall floating island doping more uniform after annealing. In addition, for the fast-opening staggered floating island device, the second doping region in contact with the fourth doping region has a high concentration, which is conducive to increasing the junction capacitance, can accommodate more charges, and reduce the voltage drop at the opening time.

[0033] By introducing a staggered floating island layer, the ability of the floating island layer to regulate the electric field in the floating island device in the blocking state can be improved. Under the premise of ensuring the blocking ability, the spacing between the floating islands of the floating island layer can be increased. For the floating island device, after multiple openings, space charges will accumulate and potential barriers will be generated, so that the width of the depletion region around the floating island will increase accordingly. The staggered floating island device increases the floating island spacing of the floating island layer, which is conducive to increasing the flow channel of electrons between the floating islands and improving the conduction ability of the floating island device after multiple openings.

[0034] By introducing a staggered floating island layer, the ability of the floating island layer to regulate the electric field in the floating island device with a heavily doped inversion region in the blocking state can be improved. Under the premise of ensuring the blocking ability, the spacing between the floating islands of the floating island layer can be increased. For the floating island device, after multiple openings, the heavily doped inversion region will accumulate positive space charges, generate potential barriers, and increase the width of the depletion region around the floating island accordingly. The staggered floating island device increases the floating island spacing of the floating island layer, which is conducive to increasing the flow channel of electrons between the floating islands and improving the conduction ability of the floating island device after multiple openings. Since multiple openings will cause the floating island to accumulate space charges, increase the electric field inside the floating island, and then increase the collision ionization inside the floating island. Therefore, after multiple openings, the carriers generated by collision ionization will neutralize the space charges increased in the floating island after each opening, so that the on-resistance of the floating island device remains unchanged.

[0035] By introducing a self-aligned manufacturing method for a rapidly-opened floating island device, after the first and second doped regions are formed by injection, an injection mask for the fourth doped region can be obtained simply by forming an oxide layer and etching back. No additional mask plate is required, which is beneficial for reducing process costs and improving manufacturing efficiency when manufacturing rapidly-opened floating island devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0036] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0037] Figure 1 A schematic diagram of the cross-sectional structure of a staggered floating island device proposed in Example 1;

[0038] Figure 2 A schematic diagram of the cross-sectional structure of a staggered floating island device proposed in Example 2;

[0039] Figure 3 A schematic diagram of the cross-sectional structure of a fast-opening staggered floating island device proposed in Example 3;

[0040] Figure 4 A schematic diagram of the cross-sectional structure of a floating island layer of a fast-opening staggered floating island device proposed in Example 3;

[0041] Figure 5 A schematic diagram of the cross-sectional structure of a floating island layer of a fast-opening staggered floating island device proposed in Example 4;

[0042] Figure 6A schematic diagram of the cross-sectional structure of a floating island layer of a fast-opening staggered floating island device proposed in Example 5;

[0043] Figure 7 A schematic diagram of the cross-sectional structure of a floating island layer of a fast-opening staggered floating island device proposed in Example 6;

[0044] Figure 8 A schematic diagram of the cross-sectional structure of a floating island layer of a fast-opening staggered floating island device proposed in Example 7;

[0045] Fig. 9 A schematic diagram of the cross-sectional structure of a floating island layer of a fast-opening staggered floating island device proposed in Example 8;

[0046] Fig.10 A schematic diagram of the cross-sectional structure of a floating island layer of a fast-opening staggered floating island device proposed in Example 9;

[0047] Fig.11 A schematic diagram of the cross-sectional structure of a floating island layer of a fast-opening staggered floating island device proposed in Example 10;

[0048] Fig.12 A schematic diagram of the cross-sectional structure of a floating island layer of a fast-opening staggered floating island device proposed in Example 11;

[0049] Fig.13 A schematic diagram of a top view of a floating island layer of a fast-opening staggered floating island device proposed in Example 12;

[0050] Fig.14 A schematic diagram of a top view of a floating island layer of a fast-opening staggered floating island device proposed in Example 13;

[0051] Fig.15 A schematic diagram of the cross-sectional structure of the surface layer of a staggered floating island device proposed in Embodiment 14 and Embodiment 15;

[0052] Fig.16 A schematic diagram of the cross-sectional structure of the surface layer of a staggered floating island device proposed in Embodiment 16 and Embodiment 17;

[0053] Fig.17 A schematic diagram of the cross-sectional structure of the surface layer of a staggered floating island device proposed in the eighteenth and nineteenth embodiments;

[0054] Fig.18 A schematic diagram of the cross-sectional structure of the surface layer of a staggered floating island device proposed in Example 20 and Example 21;

[0055] Fig.19A schematic diagram of the cross-sectional structure of the surface layer of a staggered floating island device proposed in Embodiment 22, Embodiment 23, Embodiment 24 and Embodiment 25;

[0056] Fig. 20 A schematic cross-sectional structure diagram of the bottom layer of a staggered floating island device proposed in Embodiment 14, Embodiment 15, Embodiment 16, Embodiment 17, Embodiment 18, Embodiment 19, Embodiment 20, Embodiment 21, Embodiment 22 and Embodiment 23;

[0057] Fig.21 A schematic diagram of the cross-sectional structure of the bottom layer of a staggered floating island device proposed in Embodiment 24 and Embodiment 25;

[0058] Fig. 22 A schematic diagram of the cross-sectional structure of a staggered floating island Schottky diode proposed in Example 14;

[0059] Fig.23 A schematic diagram of the cross-sectional structure of a fast-turned on staggered floating island Schottky diode proposed in Example 15;

[0060] Fig.24 A schematic diagram of the cross-sectional structure of a staggered floating island PN diode proposed in Example 16;

[0061] Fig.25 A schematic diagram of the cross-sectional structure of a fast-opening staggered floating island PN diode proposed in Example 17;

[0062] Fig.26 It is a schematic diagram of the cross-sectional structure of a staggered floating island junction barrier Schottky diode proposed in Example 18;

[0063] Fig. 27 A schematic diagram of the cross-sectional structure of a fast-turn-on staggered floating island junction barrier Schottky diode proposed in Example 19;

[0064] Fig.28 A schematic diagram of the cross-sectional structure of another staggered floating island junction barrier Schottky diode proposed in Example 20;

[0065] Fig.29 A schematic diagram of the cross-sectional structure of another fast-turn-on staggered floating island junction barrier Schottky diode proposed in Example 21;

[0066] Fig.30 A schematic diagram of the cross-sectional structure of a staggered floating island MOSFET proposed in Example 22;

[0067] Fig.31 A schematic diagram of the cross-sectional structure of a fast-turned-on staggered floating island MOSFET proposed in Example 23;

[0068] Fig.32 A schematic diagram of the cross-sectional structure of a staggered floating island IGBT proposed in Embodiment 24;

[0069] Fig.33 A schematic diagram of the cross-sectional structure of a fast-opening staggered floating island IGBT proposed in Embodiment 25;

[0070] Fig.34 A schematic cross-sectional structure diagram of a staggered three-layer floating island device proposed in Example 26;

[0071] Fig.35 A schematic cross-sectional structure diagram of a fast-opening staggered three-layer floating island device proposed in Example 27;

[0072] Fig.36 A schematic diagram of the cross-sectional structure of another fast-opening staggered three-layer floating island device proposed in Example 28;

[0073] Fig.37 A method for manufacturing a self-aligned floating island device for rapid opening proposed in Example 35;

[0074] Fig.38 The energy band distribution diagram in the cross section when the floating island device changes from the blocking state to zero bias;

[0075] Fig.39 The energy band distribution diagram in the cross section when the floating island device turns from blocking state to zero bias for fast opening;

[0076] Fig.40 The energy band distribution diagram in the cross section when the staggered floating island device changes from the blocking state to zero bias after being turned on multiple times;

[0077] Fig.41 This is the energy band distribution diagram in the cross section when the floating island device changes from a blocking state to zero bias after being opened multiple times.

[0078] Figure numerals: 1. surface layer; 2. bottom layer; 3. epitaxial layer; 4. first doped region; 5. third doped region; 6. floating island layer; 7. fourth doped region; 8. anode metal; 9. anode doped region; 10. anode epitaxial region; 11. source metal; 12. channel well doped region; 13. source doped region; 14. gate oxide layer; 15. gate metal; 16. trench filling; 17. cathode drain metal; 18. drain doped region; 19. drift region; 20. first doped region injection mask; 21. sidewall oxide layer; 22. bottom oxide layer; 23. second doped region. DETAILED DESCRIPTION

[0079] The present invention is further described in detail below in conjunction with embodiments. The following embodiments are for explanation of the present invention but the present invention is not limited to the following embodiments.

[0080] Embodiment 1

[0081] like Figure 1 As shown, in order to solve the problem that the floating island device cannot restore the conduction capability after being turned on multiple times, this embodiment proposes a basic structure of a staggered floating island device, including a surface layer 1, a bottom layer 2 and a drift region 19. The drift region 19 includes a plurality of groups of epitaxial layers 3 and a plurality of groups of floating island layers 6, and a group of floating island layers 6 is arranged between every two groups of epitaxial layers 3, or a group of epitaxial layers 3 is arranged between every two groups of floating island layers 6 (see FIG. Fig. 27 In the embodiment shown in the figure, the number of epitaxial layers 3 and floating island layers 6 can be the same or different. When the number of epitaxial layers 3 is n, the number of floating island layers 6 can be n, (n-1) or (n+1), or other values. At least two groups of floating island layers 6 are arranged in an alternating manner.

[0082] exist Figure 1 In the embodiment shown, the floating island layer 6 and the epitaxial layer 3 are combined in a staggered manner upward in sequence. The floating island device includes two groups of floating island layers 6 and three groups of epitaxial layers 3. The floating island layer 6 is sandwiched between the two groups of epitaxial layers 3. The two groups of floating island layers 6 are staggered. The epitaxial layer 3 can be doped with a concentration of ~ of semiconductor materials.

[0083] exist Figure 1 In the illustrated embodiment, the floating island layer 6 includes a first doping region 4, a second doping region 23, and a third doping region 5, wherein the second doping region 23 is distributed on the upper part of the first doping region 4, wherein the first doping region 4 and the second doping region 23 of at least one group of floating island layers 6 and the first doping region 4 and the second doping region 23 of another group of floating island layers 6 are at different positions in the horizontal direction, the first doping region 4 and the second doping region 23 are opposite to the doping type of the epitaxial layer 3, the doping concentration of the second doping region 23 is higher than that of the first doping region 4, and the third doping region 5 is the same as the doping type of the epitaxial layer 3. The doping concentration of the third doping region 5 may be equal to, higher than, or lower than the doping concentration of the epitaxial layer 3.

[0084] Taking the epitaxial layer 3 as an N-type semiconductor material as an example, the first doping region 4 can be doped with a concentration of ~ The second doping region 23 may be a P-type semiconductor material with a doping concentration of ~ The third doping region 5 may be a P-type semiconductor material with a doping concentration of ~ N-type semiconductor material, wherein, in other embodiments, a group of floating island layers 6 in a floating island device may not include the third doping region 5, and only consist of the first doping region 4 and the second doping region 23.

[0085] In this embodiment, the surface layer 1 and the bottom layer 2 may also have various designs, so as to form various devices together with the drift region 19. For example, the design of the surface layer 1 may be as follows: Figures 14 to 18 As shown, the underlying design can be Fig.19 and Fig. 20 shown.

[0086] Therefore, by introducing a second doping region 23 with a higher concentration on the top of the first doping region 4, more impurities can be diffused outward at high temperature, and the doping concentration at the edge of the floating island can be increased, so that the overall floating island doping is more uniform after annealing. In addition, by introducing a staggered floating island layer 6, the ability of the floating island layer 6 to regulate the electric field in the floating island device in the blocking state can be improved. Under the premise of ensuring the blocking ability, the interval between the first doping regions 4 of the floating island layer 6 can be increased, which is conducive to increasing the flow channel of electrons between the first doping regions 4 and improving the conduction ability of the floating island device after multiple openings.

[0087] Embodiment 2

[0088] Figure 1 There are many design options for the relative positions of adjacent floating island layers 6. Figure 2 As shown, the first doping region 4 and the second doping region 23 of the floating island layer 6 and the first doping region 4 and the second doping region 23 of another group of floating island layers may partially overlap or may not overlap in the top view direction.

[0089] Embodiment 3

[0090] At the moment when the floating island device changes from the blocking state to the conducting state, since the P-type doped region inside the drift region is not directly connected to the electrode, the hole carriers near the anode cannot enter these P-type doped regions, resulting in negative charges remaining in the P-type doped regions. In the drift region, a large number of positive charges are attracted and fill the N-type drift region in the form of space charges, generating a potential barrier, thereby hindering the flow of electron carriers, such as Fig.38 shown.

[0091] like Figure 3 As shown, in view of the problem that the floating island device cannot restore the conduction capability under the condition of low bias voltage, this embodiment proposes a basic structure of a staggered floating island device that can be turned on quickly, including a surface layer 1, a bottom layer 2 and a drift region 19. The drift region 19 includes a plurality of groups of epitaxial layers 3 and a plurality of groups of floating island layers 6, and a group of floating island layers 6 is arranged between every two groups of epitaxial layers 3, or a group of epitaxial layers 3 is arranged between every two groups of floating island layers 6 (see FIG. Fig.23In the embodiment shown in the figure), the number of epitaxial layers 3 and floating island layers 6 may be the same or different. When the number of epitaxial layers 3 is n, the number of floating island layers 6 may be n, (n-1) or (n+1), or other values.

[0092] exist Figure 3 In the embodiment shown, the floating island layer 6 and the epitaxial layer 3 are combined in a staggered manner in an upward direction. The floating island device includes a group of floating island layers 6 and two groups of epitaxial layers 3. The floating island layer 6 is sandwiched between the two groups of epitaxial layers 3. The epitaxial layer 3 may be doped with a concentration of ~ of semiconductor materials.

[0093] exist Figure 3 In the illustrated embodiment, the floating island layer 6 includes a first doping region 4, a second doping region 23, a third doping region 5 and a fourth doping region 7, wherein the second doping region 23 is distributed on the upper part of the first doping region 4, wherein the first doping region 4, the second doping region 23, the fourth doping region 7 of at least one group of floating island layers 6 and the first doping region 4, the second doping region 23, the fourth doping region 7 of another group of floating island layers 6 are at different positions in the horizontal direction, that is, wherein the first doping region 4, the second doping region 23, the fourth doping region 7 of at least one group of floating island layers 6 and the first doping region 4, the second doping region 23, the fourth doping region 7 of another group of floating island layers 6 partially overlap or do not overlap in the top view direction, the first doping region 4 and the second doping region 23 are opposite to the doping type of the epitaxial layer 3, the doping concentration of the second doping region 23 is higher than that of the first doping region 4, the third doping region 5 is the same as the doping type of the epitaxial layer 3, and the fourth doping region 7 is the same as the doping type of the epitaxial layer 3. The doping concentration of the third doping region 5 can be equal to, higher than or lower than the doping concentration of the epitaxial layer 3.

[0094] Taking the epitaxial layer 3 as an N-type semiconductor material as an example, the first doping region 4 can be doped with a concentration of ~ The second doping region 23 may be a P-type semiconductor material with a doping concentration of ~ The third doping region 5 may be a P-type semiconductor material with a doping concentration of ~ N-type semiconductor material, the fourth doping region 7 may be doped with a concentration of ~ The doping concentration of the fourth doping region 7 may be higher than the doping concentration of the epitaxial layer 3, the doping concentration of the second doping region 23 may be higher than the doping concentration of the first doping region 4, and the doping concentration of the first doping region 4 may be equal to the doping concentration of the fourth doping region 7. In other embodiments, a group of floating island layers 6 in a floating island device may not include the third doping region 5, but only consist of the first doping region 4, the second doping region 23 and the fourth doping region 7; or may not include the third doping region 5 and the fourth doping region 7, but only consist of the first doping region 4 and the second doping region 23.

[0095] like Figure 4 As shown, the length L2 of the fourth doping region 7 distributed in the second doping region 23 is less than the length L1 of the second doping region 23, the upper edge of the fourth doping region 7 coincides with the upper edge of the second doping region 23, the upper edge of the fourth doping region 7 is in direct contact with the epitaxial layer 3, and the lower edge of the fourth doping region 7 is not lower than the lower edge of the second doping region 23. In other embodiments of the present invention, the upper edge of the fourth doping region 7 may also be higher or lower than the upper edge of the second doping region 23.

[0096] In an embodiment of the present invention, the shape and position of the fourth doping region 7 can have many changes. When the length L2 of the fourth doping region 7 is greater than or equal to the length L1 of the second doping region 23, the depletion region will be blocked by the fourth doping region 7 when it expands from top to bottom when the device is blocked, so that the depletion region is cut off when it expands to the first fourth doping region 7 from the top, thereby causing premature breakdown. Therefore, the length L2 of the fourth doping region 7 can be set to be less than the length L1 of the second doping region 23. When the lower edge of the fourth doping region 7 is lower than the lower edge of the second doping region 23, it is difficult for the fourth doping region 7 to be depleted by the second doping region 23 when blocked, causing premature breakdown. Therefore, the lower edge of the fourth doping region 7 is set not lower than the lower edge of the second doping region 23. The changes in the fourth doping region 7 can be as follows: Figures 5 to 11 shown.

[0097] In this embodiment, the surface layer 1 and the bottom layer 2 may also have various designs, so as to form various devices together with the drift region 19. For example, the design of the surface layer 1 may be as follows: Figure 15 to Figure 19 As shown, the underlying design can be Fig. 20 and Fig.21 shown.

[0098] Thus, by introducing the fourth doping region 7, when the floating island device changes from a blocking state to a conducting state, the space charges in the epitaxial layer 3 are gathered in the fourth doping region 7 instead of being dispersed in the entire epitaxial layer 3, so that when the bias voltage is low, the charges in the drift region can also avoid the hindering effect on the current due to charge accumulation, so that the drift region 19 can smoothly conduct the current, and thus the floating island device can quickly restore the conduction capability even under a low bias voltage, such as Fig.39 After the floating island device is turned on multiple times, space charges will accumulate in the fourth doping region 7, generating a potential barrier and forming a depletion region around the first doping region 4, hindering the flow of electrons. Fig.41 shown.

[0099] Therefore, by introducing a second doping region 23 with a higher concentration on the top of the first doping region 4, more impurities can be diffused outward at high temperature, and the doping concentration at the edge of the floating island can be increased, so that the overall floating island doping is more uniform after annealing. In addition, for the fast-turned staggered floating island device, the second doping region 23 in contact with the fourth doping region 7 has a high concentration, which is conducive to increasing the junction capacitance, accommodating more charges, and reducing the voltage drop at the turn-on time.

[0100] Therefore, by introducing the staggered floating island layer 6, the ability of the floating island layer 6 to regulate the electric field in the floating island device in the blocking state can be improved. Under the premise of ensuring the blocking ability, the interval between the first doping regions 4 of the floating island layer 6 can be increased, which is beneficial to increase the flow channel of electrons between the first doping regions 4 after the floating island device is opened multiple times, and improve the conduction ability of the floating island device after multiple openings. Fig.40 As shown. Multiple turns on will cause the first doping region 4, the second doping region 23 and the fourth doping region 7 to accumulate space charges, increase the electric field, and thus increase the collision ionization between the first doping region 4, the second doping region 23 and the fourth doping region 7. Therefore, after multiple turns on, the carriers generated by the collision ionization will neutralize the space charges increased in the first doping region 4, the second doping region 23 and the fourth doping region 7 after each turn on, so that the on-resistance of the floating island device remains unchanged.

[0101] Embodiment 4

[0102] Figure 4 There are many design options for the floating island layer. Figure 5 As shown, the position of the fourth doping region 5 relative to the second doping region 23 can be moved to the left, for example, the left edge of the fourth doping region 7 coincides with the left edge of the second doping region 23 , or the right edge of the fourth doping region 7 coincides with the right edge of the second doping region 23 .

[0103] Embodiment 5

[0104] Figure 4 There are many design options for the floating island layer 6. Figure 6 As shown, the position of the fourth doping region 7 relative to the second doping region 23 can be moved to the left, for example, the left edge of the fourth doping region 7 extends to the left of the left edge of the second doping region 23, or the right edge of the fourth doping region 7 extends to the right of the right edge of the second doping region 23. At this time, the length L2 of the portion of the fourth doping region 7 located in the second doping region 23 is set to be less than the length L1 of the second doping region 23.

[0105] Embodiment 6

[0106] Figure 4 There are many design options for the floating island layer. Figure 7 As shown, the fourth doping region 7 may be disposed on one side of the second doping region 23 , and no fourth doping region 7 may be disposed on the other side.

[0107] Embodiment 7

[0108] Figure 4 There are many design options for the floating island layer. Figure 8 As shown, the upper edge of the fourth doping region 7 may be higher than the upper edge of the second doping region 23 , that is, a portion of the fourth doping region 7 lower than the upper edge of the second doping region 23 is distributed in the second doping region 23 .

[0109] Embodiment 8

[0110] Figure 4 There are many design options for the floating island layer. Fig. 9 As shown, the upper edge of the fourth doping region 7 may be lower than the second doping region 23. Figure 6 In the illustrated embodiment, the upper edge of the fourth doping region 7 is in direct contact with the epitaxial layer 3, that is, the fourth doping region 7 is not completely surrounded by the second doping region 23, and only the bottom and both sides are surrounded by the second doping region 23. In other embodiments, as long as the upper edge of the fourth doping region 7 is in direct contact with the epitaxial layer 3, it can be included in the protection scope of the present invention.

[0111] Embodiment 9

[0112] Figure 4 The floating island layer can have many designs and shapes. Fig.10 As shown, the shape of the fourth doping region 7 may be a sawtooth shape.

[0113] Embodiment 10

[0114] Figure 4 There are many design options for the floating island layer. Fig.11 As shown, the fourth doping region 7 may be composed of several discontinuous parts, for example, the fourth doping regions 7 distributed in the same second doping region 23 are arranged at intervals in the lateral direction. In this case, the sum of the lengths of the parts (L21, L22, L23, L24, etc.) is set to be less than the length L1 of the first doping region.

[0115] Embodiment 11

[0116] Figure 4 There are many design options for the floating island layer. Fig.12As shown, the fourth doping region 7 may also be composed of several discontinuous parts in the longitudinal direction. For example, the fourth doping regions 7 distributed in the same floating island layer 6 are arranged at intervals in the longitudinal direction. In one embodiment, one or more groups of fourth doping regions 7 may be distributed in the second doping region 23 (that is, the four sides of the one or more fourth doping regions 7 may be surrounded by the first doping region), and the lower edge of the topmost fourth doping region 7 may be flush with the upper edge of the second doping region 23 or lower than the upper edge of the second doping region 23. In other embodiments of the present invention, the fourth doping regions 7 are not limited to being arranged at intervals in the longitudinal or transverse directions, and may also be arranged at intervals in any other direction.

[0117] Embodiment 12

[0118] Figure 4 The top view of the floating island layer in the embodiment can have a variety of design schemes, and the top view shape of the fourth doping region 7 can have a variety of changes. Fig.13 As shown, the top view of the fourth doping region 7 can be square, star-shaped, circular, etc.

[0119] Embodiment 13

[0120] Figure 4 The top view of the floating island layer can have a variety of design schemes, and the top view shapes of the first doping region 4 and the second doping region 23 can have a variety of changes. Fig.14 As shown, the top view of the first doping region 4 and the second doping region 23 may be elliptical or the like.

[0121] Embodiment 14

[0122] like Fig.15 As shown, the surface layer 1 may comprise only one layer of anode metal 8 .

[0123] like Fig. 20 As shown, the bottom layer 2 may only include a layer of cathode drain metal 17 .

[0124] like Fig. 22 As shown, the surface layer 1 in the first embodiment is replaced by Fig.15 The structure shown in the figure is that the bottom layer 2 in the first embodiment is replaced by Fig. 20 The structure shown can form staggered floating island Schottky diodes.

[0125] Therefore, by introducing a second doping region 23 with a higher concentration on the top of the first doping region 4, more impurities can be diffused outward at high temperature, and the doping concentration at the edge of the floating island can be increased, so that the overall floating island doping is more uniform after annealing. In addition, by introducing a staggered floating island layer 6, the ability of the floating island layer 6 to regulate the electric field in the floating island device in the blocking state can be improved. Under the premise of ensuring the blocking ability, the interval between the first doping regions 4 of the floating island layer 6 can be increased, which is conducive to increasing the flow channel of electrons between the first doping regions 4 and improving the conduction ability of the floating island device after multiple openings.

[0126] Embodiment 15

[0127] like Fig.23 As shown, the surface layer 1 in the second embodiment is replaced by Fig.15 The structure shown in the figure is to replace the bottom layer 2 in the second embodiment with Fig. 20 The structure shown can form a fast-turned-on staggered floating-island Schottky diode.

[0128] Therefore, by introducing the fourth doping region 7, when the floating island device changes from a blocking state to a conducting state, the space charges in the epitaxial layer 3 are gathered in the fourth doping region 7 instead of being dispersed in the entire epitaxial layer 3, so that when the bias voltage is low, the charges in the drift region can also avoid the obstruction to the current due to charge accumulation, so that the drift region 19 can smoothly conduct the current, and the floating island device can quickly restore its conduction capability even under a lower bias voltage.

[0129] Therefore, by introducing a second doping region 23 with a higher concentration on the top of the first doping region 4, more impurities can be diffused outward at high temperature, and the doping concentration at the edge of the floating island can be increased, so that the overall floating island doping is more uniform after annealing. In addition, for the fast-turned staggered floating island device, the second doping region 23 in contact with the fourth doping region 7 has a high concentration, which is conducive to increasing the junction capacitance, accommodating more charges, and reducing the voltage drop at the turn-on time.

[0130] By introducing the staggered floating island layer 6, the ability of the floating island layer 6 to regulate the electric field in the floating island device in the blocking state can be improved. Under the premise of ensuring the blocking ability, the interval between the first doping regions 4 of the floating island layer 6 can be increased, which is conducive to increasing the flow channel of electrons between the first doping regions 4 after the floating island device is opened multiple times, and improving the conduction ability of the floating island device after multiple openings. Due to multiple openings, the first doping region 4, the second doping region 23 and the fourth doping region 7 will accumulate space charges, increase the electric field, and then increase the collision ionization between the first doping region 4, the second doping region 23 and the fourth doping region 7. Therefore, after multiple openings, the carriers generated by the collision ionization will neutralize the space charges increased in the first doping region 4, the second doping region 23 and the fourth doping region 7 after each opening, so that the on-resistance of the floating island device remains unchanged.

[0131] Embodiment 16

[0132] like Fig.16 As shown, the surface layer 1 may include a layer of anode metal 8 and a layer of anode doping region 9 .

[0133] like Fig. 20 As shown, the bottom layer 2 may only include a layer of cathode drain metal 17 .

[0134] like Fig.24 As shown, the surface layer 1 in the first embodiment is replaced by Fig.16 The structure shown in the figure is that the bottom layer 2 in the first embodiment is replaced by Fig. 20 The structure shown can form another staggered floating island PN diode.

[0135] The doping type of the anode doping region 9 is opposite to that of the epitaxial layer 3. Taking the epitaxial layer 3 as an example, the anode doping region 9 can be doped with a concentration of ~ P-type semiconductor material.

[0136] Therefore, by introducing a second doping region 23 with a higher concentration on the top of the first doping region 4, more impurities can be diffused outward at high temperature, and the doping concentration at the edge of the floating island can be increased, so that the overall floating island doping is more uniform after annealing. In addition, by introducing a staggered floating island layer 6, the ability of the floating island layer 6 to regulate the electric field in the floating island device in the blocking state can be improved. Under the premise of ensuring the blocking ability, the interval between the first doping regions 4 of the floating island layer 6 can be increased, which is conducive to increasing the flow channel of electrons between the first doping regions 4 and improving the conduction ability of the floating island device after multiple openings.

[0137] Embodiment 17

[0138] like Fig.25 As shown, the surface layer 1 in the second embodiment is replaced by Fig.16 The structure shown in the figure is to replace the bottom layer 2 in the second embodiment with Fig. 20 The structure shown can form another fast-turned on interleaved floating island PN diode.

[0139] The doping type of the anode doping region 9 is opposite to that of the epitaxial layer 3. Taking the epitaxial layer 3 as an example, the anode doping region 9 can be doped with a concentration of ~ P-type semiconductor material.

[0140] Therefore, by introducing the fourth doping region 7, when the floating island device changes from a blocking state to a conducting state, the space charges in the epitaxial layer 3 are gathered in the fourth doping region 7 instead of being dispersed in the entire epitaxial layer 3, so that when the bias voltage is low, the charges in the drift region can also avoid the obstruction to the current due to charge accumulation, so that the drift region 19 can smoothly conduct the current, and the floating island device can quickly restore its conduction capability even under a lower bias voltage.

[0141] Therefore, by introducing a second doping region 23 with a higher concentration on the top of the first doping region 4, more impurities can be diffused outward at high temperature, and the doping concentration at the edge of the floating island can be increased, so that the overall floating island doping is more uniform after annealing. In addition, for the fast-turned staggered floating island device, the second doping region 23 in contact with the fourth doping region 7 has a high concentration, which is conducive to increasing the junction capacitance, accommodating more charges, and reducing the voltage drop at the turn-on time.

[0142] By introducing the staggered floating island layer 6, the ability of the floating island layer 6 to regulate the electric field in the floating island device in the blocking state can be improved. Under the premise of ensuring the blocking ability, the interval between the first doping regions 4 of the floating island layer 6 can be increased, which is conducive to increasing the flow channel of electrons between the first doping regions 4 after the floating island device is opened multiple times, and improving the conduction ability of the floating island device after multiple openings. Due to multiple openings, the first doping region 4, the second doping region 23 and the fourth doping region 7 will accumulate space charges, increase the electric field, and then increase the collision ionization between the first doping region 4, the second doping region 23 and the fourth doping region 7. Therefore, after multiple openings, the carriers generated by the collision ionization will neutralize the space charges increased in the first doping region 4, the second doping region 23 and the fourth doping region 7 after each opening, so that the on-resistance of the floating island device remains unchanged.

[0143] Embodiment 18

[0144] like Fig.17 As shown, the surface layer 1 may include an anode metal 8 , an anode doping region 9 and an anode epitaxial region 10 .

[0145] like Fig. 20 As shown, the bottom layer 2 may only include a layer of cathode drain metal 17 .

[0146] like Fig.26 As shown, the surface layer 1 in the first embodiment is replaced by Fig.17 The structure shown in the figure is that the bottom layer 2 in the first embodiment is replaced by Fig. 20 The structure shown can form another staggered floating island junction barrier Schottky diode.

[0147] The doping type of the anode doping region 9 is opposite to that of the epitaxial layer 3, and the doping type of the anode epitaxial region 10 is the same as that of the epitaxial layer 3. The anode epitaxial region 10 is located on both sides or one side of the anode doping region 9. Taking the epitaxial layer 3 as an example of an N-type semiconductor material, the anode doping region 9 can be doped with a concentration of ~ The anode epitaxial region 10 may be a P-type semiconductor material with a doping concentration of ~ N-type semiconductor material.

[0148] Therefore, by introducing a second doping region 23 with a higher concentration on the top of the first doping region 4, more impurities can be diffused outward at high temperature, and the doping concentration at the edge of the floating island can be increased, so that the overall floating island doping is more uniform after annealing. In addition, by introducing a staggered floating island layer 6, the ability of the floating island layer 6 to regulate the electric field in the floating island device in the blocking state can be improved. Under the premise of ensuring the blocking ability, the interval between the first doping regions 4 of the floating island layer 6 can be increased, which is conducive to increasing the flow channel of electrons between the first doping regions 4 and improving the conduction ability of the floating island device after multiple openings.

[0149] Embodiment 19

[0150] like Fig. 27 As shown, the surface layer 1 in the second embodiment is replaced by Fig.17 The structure shown in the figure is to replace the bottom layer 2 in the second embodiment with Fig. 20 The structure shown can form another fast-turned on staggered floating island junction barrier Schottky diode.

[0151] The doping type of the anode doping region 9 is opposite to that of the epitaxial layer 3, and the doping type of the anode epitaxial region 10 is the same as that of the epitaxial layer 3. The anode epitaxial region 10 is located on both sides or one side of the anode doping region 9. Taking the epitaxial layer 3 as an example of an N-type semiconductor material, the anode doping region 9 can be doped with a concentration of ~ The anode epitaxial region 10 may be a P-type semiconductor material with a doping concentration of ~ N-type semiconductor material.

[0152] Therefore, by introducing the fourth doping region 7, when the floating island device changes from a blocking state to a conducting state, the space charges in the epitaxial layer 3 are gathered in the fourth doping region 7 instead of being dispersed in the entire epitaxial layer 3, so that when the bias voltage is low, the charges in the drift region can also avoid the obstruction to the current due to charge accumulation, so that the drift region 19 can smoothly conduct the current, and the floating island device can quickly restore its conduction capability even under a lower bias voltage.

[0153] Therefore, by introducing a second doping region 23 with a higher concentration on the top of the first doping region 4, more impurities can be diffused outward at high temperature, and the doping concentration at the edge of the floating island can be increased, so that the overall floating island doping is more uniform after annealing. In addition, for the fast-turned staggered floating island device, the second doping region 23 in contact with the fourth doping region 7 has a high concentration, which is conducive to increasing the junction capacitance, accommodating more charges, and reducing the voltage drop at the turn-on time.

[0154] By introducing the staggered floating island layer 6, the ability of the floating island layer 6 to regulate the electric field in the floating island device in the blocking state can be improved. Under the premise of ensuring the blocking ability, the interval between the first doping regions 4 of the floating island layer 6 can be increased, which is conducive to increasing the flow channel of electrons between the first doping regions 4 after the floating island device is opened multiple times, and improving the conduction ability of the floating island device after multiple openings. Due to multiple openings, the first doping region 4, the second doping region 23 and the fourth doping region 7 will accumulate space charges, increase the electric field, and then increase the collision ionization between the first doping region 4, the second doping region 23 and the fourth doping region 7. Therefore, after multiple openings, the carriers generated by the collision ionization will neutralize the space charges increased in the first doping region 4, the second doping region 23 and the fourth doping region 7 after each opening, so that the on-resistance of the floating island device remains unchanged.

[0155] Embodiment 20

[0156] like Fig.18 As shown, the surface layer 1 may include an anode metal 8 , an anode doping region 9 , an anode epitaxial region 10 and a fourth doping region 7 .

[0157] like Fig. 20 As shown, the bottom layer 2 may only include a layer of cathode drain metal 17 .

[0158] like Fig.28 As shown, the surface layer 1 in the first embodiment is replaced by Fig.18 The structure shown in the figure is that the bottom layer 2 in the first embodiment is replaced by Fig. 20 The structure shown can form another staggered floating island junction barrier Schottky diode.

[0159] The doping type of the anode doping region 9 is opposite to that of the epitaxial layer 3, the doping type of the fourth doping region 7 is the same as that of the epitaxial layer 3, and the doping type of the anode epitaxial region 10 is the same as that of the epitaxial layer 3. The anode epitaxial region 10 is located on both sides or one side of the anode doping region 9. For example, the epitaxial layer 3 is an N-type semiconductor material. At this time, the anode doping region 9 is doped with a concentration of ~ The fourth doping region 7 is a P-type semiconductor material with a doping concentration of ~ The N-type semiconductor material, the anode epitaxial region 10 may be doped with a concentration of ~ N-type semiconductor material.

[0160] Therefore, by introducing a second doping region 23 with a higher concentration on the top of the first doping region 4, more impurities can be diffused outward at high temperature, and the doping concentration at the edge of the floating island can be increased, so that the overall floating island doping is more uniform after annealing. In addition, by introducing a staggered floating island layer 6, the ability of the floating island layer 6 to regulate the electric field in the floating island device in the blocking state can be improved. Under the premise of ensuring the blocking ability, the interval between the first doping regions 4 of the floating island layer 6 can be increased, which is conducive to increasing the flow channel of electrons between the first doping regions 4 and improving the conduction ability of the floating island device after multiple openings.

[0161] Embodiment 21

[0162] like Fig.29 As shown, the surface layer 1 in the second embodiment is replaced by Fig.18 The structure shown in the figure is to replace the bottom layer 2 in the second embodiment with Fig. 20 The structure shown can form another fast-turned on staggered floating island junction barrier Schottky diode.

[0163] The doping type of the anode doping region 9 is opposite to that of the epitaxial layer 3, the doping type of the fourth doping region 7 is the same as that of the epitaxial layer 3, the doping type of the anode epitaxial region 10 is the same as that of the epitaxial layer 3, and the anode epitaxial region 10 is located on both sides or one side of the anode doping region 9. Taking the epitaxial layer 3 as an example of N-type semiconductor material, the anode doping region 9 is doped with a concentration of ~ The fourth doping region 7 is a P-type semiconductor material with a doping concentration of ~ The N-type semiconductor material, the anode epitaxial region 10 may be doped with a concentration of ~ N-type semiconductor material.

[0164] Therefore, by introducing the fourth doping region 7, when the floating island device changes from a blocking state to a conducting state, the space charges in the epitaxial layer 3 are gathered in the fourth doping region 7 instead of being dispersed in the entire epitaxial layer 3, so that when the bias voltage is low, the charges in the drift region can also avoid the obstruction to the current due to charge accumulation, so that the drift region 19 can smoothly conduct the current, and the floating island device can quickly restore its conduction capability even under a lower bias voltage.

[0165] Therefore, by introducing a second doping region 23 with a higher concentration on the top of the first doping region 4, more impurities can be diffused outward at high temperature, and the doping concentration at the edge of the floating island can be increased, so that the overall floating island doping is more uniform after annealing. In addition, for the fast-turned staggered floating island device, the second doping region 23 in contact with the fourth doping region 7 has a high concentration, which is conducive to increasing the junction capacitance, accommodating more charges, and reducing the voltage drop at the turn-on time.

[0166] By introducing the staggered floating island layer 6, the ability of the floating island layer 6 to regulate the electric field in the floating island device in the blocking state can be improved. Under the premise of ensuring the blocking ability, the interval between the first doping regions 4 of the floating island layer 6 can be increased, which is conducive to increasing the flow channel of electrons between the first doping regions 4 after the floating island device is opened multiple times, and improving the conduction ability of the floating island device after multiple openings. Due to multiple openings, the first doping region 4, the second doping region 23 and the fourth doping region 7 will accumulate space charges, increase the electric field, and then increase the collision ionization between the first doping region 4, the second doping region 23 and the fourth doping region 7. Therefore, after multiple openings, the carriers generated by the collision ionization will neutralize the space charges increased in the first doping region 4, the second doping region 23 and the fourth doping region 7 after each opening, so that the on-resistance of the floating island device remains unchanged.

[0167] Embodiment 22

[0168] like Fig.19 As shown, the surface layer 1 may include a source metal 11 , a channel well doping region 12 , a source doping region 13 , a gate oxide layer 14 , a gate metal 15 , and a trench filler 16 .

[0169] like Fig. 20 As shown, the bottom layer 2 may only include a layer of cathode drain metal 17 .

[0170] like Fig.30 As shown, the surface layer 1 in the first embodiment is replaced by Fig.19 The structure shown in the figure is that the bottom layer 2 in the first embodiment is replaced by Fig. 20 The structure shown can form a staggered floating island MOSFET. In other embodiments of the present invention, the floating island MOSFET structure is not limited to trench MOSFET, but can also be any other MOSFET structure such as planar MOSFET, and the MOSFET includes source metal, cathode drain, channel well doping region, source doping region, gate oxide layer and gate metal.

[0171] The doping type of the channel well doping region 12 is opposite to that of the epitaxial layer 3, the doping type of the source doping region 13 is the same as that of the epitaxial layer 3, the gate oxide layer 14 can be an insulating oxide layer, and the trench filler 16 can be an insulator, a conductor or a semiconductor. Taking the epitaxial layer 3 as an example of an N-type semiconductor material, the channel well doping region 12 can be doped with a concentration of ~ The source doping region 13 may be a P-type semiconductor material with a doping concentration of ~ N-type semiconductor material.

[0172] Therefore, by introducing a second doping region 23 with a higher concentration on the top of the first doping region 4, more impurities can be diffused outward at high temperature, and the doping concentration at the edge of the floating island can be increased, so that the overall floating island doping is more uniform after annealing. In addition, by introducing a staggered floating island layer 6, the ability of the floating island layer 6 to regulate the electric field in the floating island device in the blocking state can be improved. Under the premise of ensuring the blocking ability, the interval between the first doping regions 4 of the floating island layer 6 can be increased, which is conducive to increasing the flow channel of electrons between the first doping regions 4 and improving the conduction ability of the floating island device after multiple openings.

[0173] Embodiment 23

[0174] like Fig.19 As shown, the surface layer 1 may include a source metal 11 , a channel well doping region 12 , a source doping region 13 , a gate oxide layer 14 , a gate metal 15 , and a trench filler 16 .

[0175] like Fig. 20 As shown, the bottom layer 2 may only include a layer of cathode drain metal 17 .

[0176] like Fig.31 As shown, the surface layer 1 in the second embodiment is replaced by Fig.19 The structure shown in the figure is to replace the bottom layer 2 in the second embodiment with Fig. 20 The structure shown can form a staggered floating island MOSFET that is quickly turned on. In other embodiments of the present invention, the floating island MOSFET structure is not limited to trench MOSFET, but can also be any other MOSFET structure such as planar MOSFET, and the MOSFET includes a source metal, a cathode drain, a channel well doping region, a source doping region, a gate oxide layer and a gate metal.

[0177] The doping type of the channel well doping region 12 is opposite to that of the epitaxial layer 3, the doping type of the source doping region 13 is the same as that of the epitaxial layer 3, the gate oxide layer 14 can be an insulating oxide layer, and the trench filler 16 can be an insulator, a conductor or a semiconductor. Taking the epitaxial layer 3 as an example of an N-type semiconductor material, the channel well doping region 12 can be doped with a concentration of ~ The source doping region 13 may be a P-type semiconductor material with a doping concentration of ~ N-type semiconductor material.

[0178] Therefore, by introducing the fourth doping region 7, when the floating island device changes from a blocking state to a conducting state, the space charges in the epitaxial layer 3 are gathered in the fourth doping region 7 instead of being dispersed in the entire epitaxial layer 3, so that when the bias voltage is low, the charges in the drift region can also avoid the obstruction to the current due to charge accumulation, so that the drift region 19 can smoothly conduct the current, and the floating island device can quickly restore its conduction capability even under a lower bias voltage.

[0179] Therefore, by introducing a second doping region 23 with a higher concentration on the top of the first doping region 4, more impurities can be diffused outward at high temperature, and the doping concentration at the edge of the floating island can be increased, so that the overall floating island doping is more uniform after annealing. In addition, for the fast-turned staggered floating island device, the second doping region 23 in contact with the fourth doping region 7 has a high concentration, which is conducive to increasing the junction capacitance, accommodating more charges, and reducing the voltage drop at the turn-on time.

[0180] By introducing the staggered floating island layer 6, the ability of the floating island layer 6 to regulate the electric field in the floating island device in the blocking state can be improved. Under the premise of ensuring the blocking ability, the interval between the first doping regions 4 of the floating island layer 6 can be increased, which is conducive to increasing the flow channel of electrons between the first doping regions 4 after the floating island device is opened multiple times, and improving the conduction ability of the floating island device after multiple openings. Due to multiple openings, the first doping region 4, the second doping region 23 and the fourth doping region 7 will accumulate space charges, increase the electric field, and then increase the collision ionization between the first doping region 4, the second doping region 23 and the fourth doping region 7. Therefore, after multiple openings, the carriers generated by the collision ionization will neutralize the space charges increased in the first doping region 4, the second doping region 23 and the fourth doping region 7 after each opening, so that the on-resistance of the floating island device remains unchanged.

[0181] Embodiment 24

[0182] like Fig.19 As shown, the surface layer 1 may include a source metal 11 , a channel well doping region 12 , a source doping region 13 , a gate oxide layer 14 , a gate metal 15 , and a trench filler 16 .

[0183] like Fig.21 As shown, the bottom layer 2 may include a layer of drain doping region 18 and a layer of cathode drain metal 17 .

[0184] like Fig.32 As shown, the surface layer 1 in the first embodiment is replaced by Fig.19 The structure shown in the figure is that the bottom layer 2 in the first embodiment is replaced by Fig.21 The structure shown can form staggered floating island IGBTs.

[0185] The doping type of the channel well doping region 12 is opposite to that of the epitaxial layer 3, the doping type of the source doping region 13 is the same as that of the epitaxial layer 3, the doping type of the drain doping region 18 is opposite to that of the epitaxial layer 3, the gate oxide layer 14 is an insulating oxide layer, and the trench filler 16 can be an insulator, a conductor or a semiconductor. Taking the epitaxial layer 3 as an example of an N-type semiconductor material, the channel well doping region 12 can be doped with a concentration of ~ The source doping region 13 may be a P-type semiconductor material with a doping concentration of ~ The drain doping region 18 may be an N-type semiconductor material with a doping concentration of ~ P-type semiconductor material.

[0186] Therefore, by introducing a second doping region 23 with a higher concentration on the top of the first doping region 4, more impurities can be diffused outward at high temperature, and the doping concentration at the edge of the floating island can be increased, so that the overall floating island doping is more uniform after annealing. In addition, by introducing a staggered floating island layer 6, the ability of the floating island layer 6 to regulate the electric field in the floating island device in the blocking state can be improved. Under the premise of ensuring the blocking ability, the interval between the first doping regions 4 of the floating island layer 6 can be increased, which is conducive to increasing the flow channel of electrons between the first doping regions 4 and improving the conduction ability of the floating island device after multiple openings.

[0187] Embodiment 25

[0188] like Fig.19 As shown, the surface layer 1 may include a source metal 11 , a channel well doping region 12 , a source doping region 13 , a gate oxide layer 14 , a gate metal 15 , and a trench filler 16 .

[0189] like Fig.21 As shown, the bottom layer 2 may include a layer of drain doping region 18 and a layer of cathode drain metal 17 .

[0190] like Fig.33 As shown, the surface layer 1 in the second embodiment is replaced by Fig.19 The structure shown in the figure is to replace the bottom layer 2 in the second embodiment with Fig.21 The structure shown can form staggered floating island IGBTs that can be turned on quickly.

[0191] The doping type of the channel well doping region 12 is opposite to that of the epitaxial layer 3, the doping type of the source doping region 13 is the same as that of the epitaxial layer 3, the doping type of the drain doping region 18 is opposite to that of the epitaxial layer 3, the gate oxide layer 14 is an insulating oxide layer, and the trench filler 16 can be an insulator, a conductor or a semiconductor. Taking the epitaxial layer 3 as an example of an N-type semiconductor material, the channel well doping region 12 can be doped with a concentration of ~ The source doping region 13 may be a P-type semiconductor material with a doping concentration of ~ The drain doping region 18 may be an N-type semiconductor material with a doping concentration of ~ P-type semiconductor material.

[0192] Therefore, by introducing the fourth doping region 7, when the floating island device changes from a blocking state to a conducting state, the space charges in the epitaxial layer 3 are gathered in the fourth doping region 7 instead of being dispersed in the entire epitaxial layer 3, so that when the bias voltage is low, the charges in the drift region can also avoid the obstruction to the current due to charge accumulation, so that the drift region 19 can smoothly conduct the current, and the floating island device can quickly restore its conduction capability even under a lower bias voltage.

[0193] Therefore, by introducing a second doping region 23 with a higher concentration on the top of the first doping region 4, more impurities can be diffused outward at high temperature, and the doping concentration at the edge of the floating island can be increased, so that the overall floating island doping is more uniform after annealing. In addition, for the fast-turned staggered floating island device, the second doping region 23 in contact with the fourth doping region 7 has a high concentration, which is conducive to increasing the junction capacitance, accommodating more charges, and reducing the voltage drop at the turn-on time.

[0194] By introducing the staggered floating island layer 6, the ability of the floating island layer 6 to regulate the electric field in the floating island device in the blocking state can be improved. Under the premise of ensuring the blocking ability, the interval between the first doping regions 4 of the floating island layer 6 can be increased, which is conducive to increasing the flow channel of electrons between the first doping regions 4 after the floating island device is opened multiple times, and improving the conduction ability of the floating island device after multiple openings. Due to multiple openings, the first doping region 4, the second doping region 23 and the fourth doping region 7 will accumulate space charges, increase the electric field, and then increase the collision ionization between the first doping region 4, the second doping region 23 and the fourth doping region 7. Therefore, after multiple openings, the carriers generated by the collision ionization will neutralize the space charges increased in the first doping region 4, the second doping region 23 and the fourth doping region 7 after each opening, so that the on-resistance of the floating island device remains unchanged.

[0195] Embodiment 26

[0196] The drift region 19 may be formed by a plurality of groups of epitaxial layers 3 and a plurality of groups of floating island layers 6 being arranged alternately in the vertical direction.

[0197] like Fig.34 As shown, the drift region 19 is formed by staggered arrangement of four epitaxial layers 3 and three floating island layers 6. In other embodiments, the number of epitaxial layers 3 and floating island layers 6 can be set according to actual needs.

[0198] Embodiment 27

[0199] like Fig.35 As shown, different from the embodiment 26, the three floating island layers 6 in the drift region 19 adopt different designs (for example, the three groups of floating island layers adopt Figure 4 , Figure 5 and Fig.11 The structure shown in the embodiment).

[0200] Embodiment 28

[0201] like Fig.36 As shown, different from the twenty-sixth embodiment, the upper edge of the fourth doping region 7 in the three floating island layers 6 in the drift region 19 can be higher than, equal to, or lower than the upper edge of the second doping region 23 (for example, the three groups of floating island layers are respectively Figure 4 , Figure 8 and Fig. 9 The structure shown in the embodiment).

[0202] Embodiment 29

[0203] Fig.34 The structure in the paper can have many variations in the dimension perpendicular to the paper.

[0204] The first doping region 4 , the second doping region 23 , and the third doping region 5 may extend to the entire cell in the third dimension.

[0205] Embodiment 30

[0206] Fig.34 The structure in the paper can have many variations in the dimension perpendicular to the paper.

[0207] The third doping region 5 extends to the entire cell in the third dimension, while only a portion of the first doping region 4 and the second doping region 23 extends in the third dimension.

[0208] Embodiment 31

[0209] Fig.34 The structure in the paper can have many variations in the dimension perpendicular to the paper.

[0210] The first doping region 4 , the second doping region 23 , the third doping region 5 and the fourth doping region 7 extend to the entire cell in the third dimension.

[0211] Embodiment 32

[0212] Fig.34 The structure in the paper can have many variations in the dimension perpendicular to the paper.

[0213] The first doping region 4 , the second doping region 23 and the third doping region 5 extend to the entire cell in the third dimension, while only a portion of the fourth doping region 7 extends in the third dimension.

[0214] Embodiment 33

[0215] Fig.34 The structure in the paper can have many variations in the dimension perpendicular to the paper.

[0216] The first doping region 4 and the second doping region 23 extend to the entire cell in the third dimension, while the third doping region 5 and the fourth doping region 7 only partially extend in the third dimension, and the fourth doping region 7 may not be provided in some second doping regions 23 .

[0217] Embodiment 34

[0218] A method for manufacturing an interlaced floating island device comprises the following steps: forming an epitaxial layer 3 by an epitaxial growth method, and forming a first doping region 4, a second doping region 23, and a third doping region 5 in the epitaxial layer 3 by a photolithography method, an ion implantation method, etc., thereby forming a floating island layer 6; repeating the above steps several times, so that several groups of epitaxial layers 3 and several groups of floating island layers 6 are interlaced in the vertical direction to form a drift region 19; at least two groups of floating island layers 6 are interlaced in the horizontal direction; and forming metal electrodes at both ends of the drift region 19 by sputtering, evaporation or annealing, wherein the metal electrode close to the epitaxial layer 3 is a surface layer 1, and the metal electrode close to the floating island layer 6 is a bottom layer 2.

[0219] The manufacturing method described in this embodiment takes the eighteenth embodiment as an example. First, an epitaxial layer 3 is obtained by epitaxial growth, and the epitaxial layer 3 has a doping concentration of ~ N-type semiconductor material is then formed in the epitaxial layer 3 through photolithography and P-type ion implantation to form a first doping region 4, a second doping region 23, and a third doping region 5, thereby forming a floating island layer 6. The epitaxial layer 3 is then repeatedly stacked to form a floating island layer 6. This operation is repeated as many times as required by actual production requirements to obtain a drift region 8.

[0220] After completing the preparation of the drift region 19, a surface layer 1 and a bottom layer 2 are formed at both ends of the drift region 19 by metal sputtering or metal evaporation, and then high-temperature annealing is performed to form ohmic contacts between the bottom layer 2 and the epitaxial layer 3, and between the surface layer 1 and the first doping region 4 and the second doping region 23, so that a Schottky contact is formed between the surface layer 1 and the third doping region 5. During the high-temperature annealing process, the metal will form an alloy with the epitaxial layer 3, the first doping region 4, and the second doping region 23, thereby achieving ohmic contact. In this embodiment, the temperature of the high-temperature annealing can be set to one thousand degrees to complete the manufacturing process.

[0221] Embodiment 35

[0222] A method for manufacturing a self-aligned floating island device for rapid opening, comprising the following steps: forming an epitaxial layer 3 by an epitaxial growth method, and forming a first doping region 4, a second doping region 23, and a third doping region 5 in the epitaxial layer 3 by a photolithography method, an ion implantation method, etc.; retaining the implantation mask of the first doping region 4 and the second doping region 23, and forming a bottom oxide layer 22 at the bottom of the mask etching groove and a sidewall oxide layer 21 on the sidewall by low-pressure chemical vapor deposition or other methods; etching back the silicon oxide and making it contact with the bottom oxide layer; The etching rate of layer 22 is higher than that of the side wall oxide layer 21, forming an injection mask for the fourth doping region 7, and the fourth doping region 7 is formed by ion implantation; thereby forming a floating island layer 6; repeating the above steps several times, so that several groups of epitaxial layers 3 and several groups of floating island layers 6 are staggered in the vertical direction to form a drift region 19; metal electrodes are formed at both ends of the drift region 19 by sputtering, evaporation or annealing, wherein the metal electrode close to the epitaxial layer 3 is the surface layer 1, and the metal electrode close to the floating island layer 6 is the bottom layer 2.

[0223] The manufacturing method described in this embodiment takes the nineteenth embodiment as an example. First, an epitaxial layer 3 is obtained by epitaxial growth, and the epitaxial layer 3 has a doping concentration of ~ N-type semiconductor material is then formed by photolithography, P-type ion implantation, oxide layer formation, back etching, and N-type ion implantation to form a first doping region 4, a second doping region 23, a third doping region 5, and a fourth doping region 7 in the epitaxial layer 3, thereby forming a floating island layer 6. The epitaxial layer 3 is then repeatedly stacked to form a floating island layer 6. This operation is repeated as many times as required by actual production requirements to obtain a drift region 8.

[0224] After completing the preparation of the drift region 19, a surface layer 1 and a bottom layer 2 are formed at both ends of the drift region 19 by metal sputtering or metal evaporation, and then high-temperature annealing is performed to form ohmic contacts between the bottom layer 2 and the epitaxial layer 3, and between the surface layer 1 and the first doping region 4 and the second doping region 23, so that a Schottky contact is formed between the surface layer 1 and the third doping region 5. During the high-temperature annealing process, the metal will form an alloy with the epitaxial layer 3, the first doping region 4, and the second doping region 23, thereby achieving ohmic contact. In this embodiment, the temperature of the high-temperature annealing can be set to one thousand degrees to complete the manufacturing process.

[0225] In addition, it should be noted that the shapes and names of the parts and components of the specific embodiments described in this specification may be different. All equivalent or simple changes made based on the structure, features and principles described in the patent concept of the present invention are included in the protection scope of the patent of the present invention. The technicians in the technical field of the present invention can make various modifications or supplements or combinations or replace the specific embodiments described in a similar manner, as long as they do not deviate from the structure of the present invention or exceed the scope defined by the claims, they should all fall within the protection scope of the present invention.

Claims

1. A fast-opening staggered floating island device, characterized in that: The invention comprises a surface layer, a bottom layer and a drift region, wherein the drift region comprises a plurality of epitaxial layers and a plurality of floating island layers, wherein a floating island layer is arranged between every two epitaxial layers, or a floating island layer is arranged between every two floating island layers, wherein there are at least two floating island layers, wherein at least two floating island layers are provided with a first doping region, a second doping region and a fourth doping region, wherein the second doping region is distributed on the upper part of the first doping region, the fourth doping region is distributed in the second doping region or part of the fourth doping region is distributed in the second doping region, the concentration of the second doping region is higher than that of the first doping region, and the first doping region is The doping type of the doped region and the second doped region is opposite to that of the epitaxial layer, and the doping type of the fourth doped region is the same as that of the epitaxial layer, wherein the first doping region, the second doping region, and the fourth doping region of at least one group of floating island layers and the first doping region, the second doping region, and the fourth doping region of another group of floating island layers are different in horizontal position, that is, the first doping region, the second doping region, and the fourth doping region of at least one group of floating island layers and the first doping region, the second doping region, and the fourth doping region of another group of floating island layers partially overlap or have no overlap in the top view direction, and the surface layer and the bottom layer are located at both ends of the drift region.

2. A fast-opening staggered floating island device according to claim 1, characterized in that: The at least two groups of floating island layers further include a third doping region, and the third doping region has the same doping type as the epitaxial layer.

3. A fast-opening staggered floating island device according to claim 1, characterized in that: The lower edge of the fourth doping region is not lower than the lower edge of the second doping region, and the upper edge of the fourth doping region is in direct contact with the epitaxial layer.

4. A fast-opening staggered floating island device according to claim 1, characterized in that: The length of the fourth doping region distributed in the second doping region is shorter than the length of the second doping region.

5. A fast-opening staggered floating island device according to claim 1, characterized in that: The floating island layer includes a plurality of fourth doped regions arranged at intervals.

6. A fast-opening staggered floating island device according to claim 5, characterized in that: The total length of the plurality of fourth doping regions arranged at intervals is smaller than the length of the second doping region.

7. A fast-opening staggered floating island device according to claim 1, characterized in that: When the fast-turn-on staggered floating island device is a fast-turn-on staggered floating island Schottky diode, the surface layer includes anode metal, and the bottom layer includes cathode drain metal; When the fast-turn-on staggered floating island device is a fast-turn-on staggered floating island PN diode, the surface layer includes an anode metal and an anode doping region, the doping type of the anode doping region is opposite to that of the epitaxial layer, and the bottom layer includes a cathode drain metal; as well as When the fast-turn-on staggered floating island device is a fast-turn-on staggered floating island junction barrier Schottky diode, the surface layer includes an anode metal, an anode doping region and an anode epitaxial region, the doping type of the anode doping region is opposite to that of the epitaxial layer, the doping type of the anode epitaxial region is the same as that of the epitaxial layer, and the bottom layer includes a cathode drain metal.

8. A fast-opening staggered floating island device according to claim 1, characterized in that: When the fast-turn-on staggered floating island device is a fast-turn-on staggered floating island junction barrier Schottky diode, the surface layer further includes a fourth doped region.

9. A fast-opening staggered floating island device according to claim 1, characterized in that: When the fast-turning staggered floating island device is a fast-turning staggered floating island MOSFET, the surface layer includes source metal, channel well doping region, source doping region, gate oxide layer and gate metal, and the bottom layer includes cathode drain metal; when the fast-turning staggered floating island device is a fast-turning staggered floating island IGBT, the surface layer includes source metal, channel well doping region, source doping region, gate oxide layer and gate metal, and the bottom layer includes cathode drain metal and drain doping region.

10. A fast-opening staggered floating island device according to claim 1, characterized in that: The structure of each group of floating island layers is the same or different.

11. A fast-opening staggered floating island device according to claim 1, characterized in that: In the three-dimensional structure, the first doping region, the second doping region, the third doping region and the fourth doping region extend to the entire cell in the third dimension; or the first doping region, the second doping region and the third doping region extend to the entire cell in the third dimension, while only a portion of the fourth doping region extends in the third dimension; or the third doping region extends to the entire cell in the third dimension, while only a portion of the fourth doping region and the first doping region and the second doping region extend in the third dimension.

12. A fast-opening staggered floating island device according to claim 1, characterized in that: An upper edge of the fourth doping region is higher than, equal to, or lower than an upper edge of the second doping region.

13. A fast-opening staggered floating island device according to claim 1, characterized in that: There are at least three groups of floating island layers, and the floating island layers are provided with a first doping region, a second doping region and a fourth doping region. The second doping region is distributed on the upper part of the first doping region, and the fourth doping region is in direct contact with the second doping region. The doping concentration of the fourth doping region is higher than the doping concentration of the epitaxial layer, and the upper edge of the fourth doping region is in direct contact with the epitaxial layer.

14. A fast-opening staggered floating island device according to claim 13, characterized in that: The lower edge of the fourth doping region is not lower than the lower edge of the second doping region, and the length of the fourth doping region distributed in the second doping region is shorter than the length of the second doping region.

15. A fast-opening staggered floating island device according to claim 14, characterized in that: When the fast-turn-on staggered floating island device is a fast-turn-on staggered floating island Schottky diode, the surface layer includes anode metal, and the bottom layer includes cathode drain metal; When the fast-turn-on staggered floating island device is a fast-turn-on staggered floating island PN diode, the surface layer includes an anode metal and an anode doping region, the doping type of the anode doping region is opposite to that of the epitaxial layer, and the bottom layer includes a cathode drain metal; When the fast-on staggered floating island device is a fast-on staggered floating island junction barrier Schottky diode, the surface layer includes an anode metal, an anode doped region and an anode epitaxial region or the surface layer includes an anode metal, an anode doped region, an anode epitaxial region and a third doped region, the doping type of the anode doped region is opposite to that of the epitaxial layer, the doping type of the anode epitaxial region is the same as that of the epitaxial layer, and the bottom layer includes a cathode drain metal; When the fast-on staggered floating island device is a fast-on staggered floating island MOSFET, the surface layer includes a source metal, a channel well doping region, a source doping region, a gate oxide layer and a gate metal, and the bottom layer includes a cathode drain metal; as well as When the fast-turn-on staggered floating island device is a fast-turn-on staggered floating island IGBT, the surface layer includes source metal, channel well doping region, source doping region, gate oxide layer and gate metal, and the bottom layer includes cathode drain metal and drain doping region.

16. A method for manufacturing a self-aligned floating island device for rapid opening, characterized in that: The manufacturing method is used to manufacture the fast-opening staggered floating island device as described in any one of claims 1-15.

17. A method for manufacturing a self-aligned floating island device for rapid opening according to claim 16, characterized in that: When the manufacturing method is used to manufacture a fast-turn-on staggered floating island Schottky diode, it comprises the following steps: growing an N-type epitaxial layer on the N-type epitaxial layer; Forming a first doping region and a second doping region by photolithography and P-type ion implantation; Retain the injection mask of the first doping region, and form a bottom oxide layer at the bottom of the mask etching groove and a sidewall oxide layer on the sidewall by low-pressure chemical vapor deposition or other methods; etch back the silicon oxide so that its etching rate for the bottom oxide layer is higher than that for the sidewall oxide layer, to form an injection mask for the fourth doping region, and then form the fourth doping region by N-type ion implantation, and form a floating island layer in the N-type epitaxial layer, wherein the floating island layer comprises a first doping region, a second doping region, a third doping region and a fourth doping region, wherein the fourth doping region is distributed in the second doping region or part of the fourth doping region is distributed in the second doping region, the first doping region and the second doping region are opposite to the doping type of the epitaxial layer, the doping type of the third doping region is the same as the doping type of the epitaxial layer, and the fourth doping region is the same as the doping type of the epitaxial layer; Repeatedly stacking N-type epitaxial layers and forming floating island layers; A surface layer and a bottom layer are formed at both ends of the drift region by metal sputtering or metal evaporation, and then high-temperature annealing is performed to form an ohmic contact between the bottom layer and the N-type epitaxial layer, and a Schottky contact between the surface layer and the N-type epitaxial layer.

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