Scintillator detector with photonic crystal microstructure and preparation method

Abstract

The invention discloses a scintillator detector with a photonic crystal microstructure and a preparation method, and relates to the field of high-energy ray detection.The scintillator detector comprises a scintillator, a transmission layer, the photonic crystal microstructure and a light detection unit, the scintillator is located above the photonic crystal microstructure, and the transmission layer is located above the photonic crystal microstructure; the photonic crystal microstructure is arranged on the transmission layer, and the transmission layer is arranged on the optical detection unit; the scintillator absorbs incident particles and generates an optical signal incident to the photonic crystal microstructure, the photonic crystal microstructure focuses the optical signal and transmits the optical signal to a detection area of the optical detection unit through the transmission layer, and the optical detection unit converts the received optical signal into an electric signal. According to the scintillator detector, the field angle of the optical detection unit is increased by using the photonic crystal microstructure, and the efficiency of the scintillator fluorescence entering the optical detection unit is greatly improved, so that the sensitivity and the signal-to-noise ratio of the scintillator detector are improved.

Description

Technical Field

[0001] The invention relates to the technical field of high-energy ray detection, and in particular to a scintillator detector with a photonic crystal microstructure and a preparation method thereof. Background Art

[0002] In the field of high-energy ray detection, the detector is responsible for converting high-energy rays into electrical signals: electron-hole pairs, which are provided to the subsequent readout circuit for measurement and processing to obtain information such as the energy and time of the high-energy rays. At present, the most widely used high-energy ray detector solution is based on the indirect detection principle, that is, high-energy rays are first converted into visible light, and then detected by visible light detectors, with two conversion processes in between. Multiple conversions will cause the original signal-to-noise ratio to be lost, and there are certain limitations in detecting weak signals.

[0003] The detection area is an important parameter of the detection device, which determines the field of view of the detector. Increasing the detector area can receive more signals, but it will also lead to an increase in dark current and junction capacitance. The area of ​​the detector is proportional to the capacitance, that is, the larger the device size, the lower the RC frequency, and the smaller the device cutoff frequency. Therefore, the detection area and response frequency of the device are a pair of contradictory parameters, and are also the main factors restricting the high-speed development of detectors. Summary of the invention

[0004] In view of the above problems and technical requirements, the inventors have proposed a scintillator detector with a photonic crystal microstructure and a preparation method thereof. The technical solution of the present invention is as follows:

[0005] A scintillator detector with a photonic crystal microstructure comprises a scintillator, a transmission layer, a photonic crystal microstructure and a light detection unit, wherein:

[0006] The scintillator is located above the photonic crystal microstructure, the photonic crystal microstructure is arranged on the transmission layer, and the transmission layer is arranged on the light detection unit;

[0007] The scintillator absorbs incident particles and generates a light signal that is incident on the photonic crystal microstructure. The photonic crystal microstructure focuses the light signal and transmits it through the transmission layer to the detection area of ​​the light detection unit. The light detection unit converts the received light signal into an electrical signal.

[0008] A further technical solution is that the photonic crystal microstructure is an array structure or a ring structure;

[0009] When the photonic crystal microstructure is an array structure, it includes a plurality of columns distributed on the transmission layer according to a first preset period, and the horizontal cross-section of the column is circular, rectangular or regular polygonal;

[0010] When the photonic crystal microstructure is a ring structure, it includes a plurality of ring bodies concentrically distributed on the transmission layer according to a second preset period, and the ring bodies are in the shape of a circular ring or an elliptical ring.

[0011] A further technical solution is that when the photonic crystal microstructure is an array structure, on a cross section of the photonic crystal microstructure, the duty cycle of the photonic crystal microstructure decreases from the center to the edge of the photonic crystal microstructure;

[0012] When the photonic crystal microstructure is a ring-shaped structure, on the central cross-section of the photonic crystal microstructure, the duty cycle of the photonic crystal microstructure decreases from the center to the edge of the photonic crystal microstructure.

[0013] A further technical solution is that a transparent medium for improving the support of the photonic crystal microstructure is filled between adjacent columns and rings, and the first preset period and the second preset period are determined according to the scintillator fluorescence wavelength.

[0014] A further technical solution is that the thickness of the transmission layer is adapted to the focal length of the photonic crystal microstructure, and the refractive index of the transmission layer is different from the refractive index of the photonic crystal microstructure.

[0015] A further technical solution is that it also includes a transparent metal layer for preventing incident particles from entering the photonic crystal microstructure. The transparent metal layer is prepared on the photonic crystal microstructure, and the material of the transparent metal layer includes gold, silver, indium tin oxide or zirconium oxide.

[0016] A further technical solution is that the light detection unit includes a substrate and a high-reflection film, the substrate has a front side and a back side corresponding to the front side, and the high-reflection film is arranged on the back side of the substrate;

[0017] The high-reflection film comprises a plurality of stacked composite films, wherein the composite film comprises at least a first refractive film and a second refractive film stacked on top of each other, wherein the first refractive film is stacked on the second refractive film, and the refractive index of the first refractive film is less than the refractive index of the second refractive film;

[0018] The film thickness of the first refractive film and the second refractive film is a multiple of one quarter of the peak wavelength of the scintillator fluorescence.

[0019] A further technical solution is that the light detection unit further includes an N-type doping region, a P-type doping region, a dielectric layer and a metal layer, and the metal layer includes a first electrode metal and a second electrode metal, wherein:

[0020] The N-type doping region and the P-type doping region are arranged in the substrate and isolated by the substrate, the dielectric layer is prepared on the front side of the substrate, the first electrode metal and the second electrode metal are supported on the dielectric layer, and the first electrode metal and the second electrode metal are spaced apart;

[0021] The first electrode metal is in ohmic contact with the P-type doping region, and the second electrode metal is in ohmic contact with the N-type doping region.

[0022] A further technical solution is that a passivation layer is prepared on the metal layer, and the passivation layer is provided with a first lead-out hole and a second lead-out hole, the first lead-out hole is located above the first electrode metal, and the second lead-out hole is located above the second electrode metal.

[0023] A method for preparing a scintillator detector having a photonic crystal microstructure, used for preparing the above-mentioned scintillator detector having a photonic crystal microstructure, the preparation method comprising:

[0024] Prepare a light detection unit, prepare a transmission layer on the light detection unit, and prepare a photonic crystal microstructure and a scintillator on the transmission layer, wherein the scintillator is located above the photonic crystal microstructure;

[0025] The scintillator absorbs incident particles and generates a light signal that is incident on the photonic crystal microstructure. The photonic crystal microstructure focuses the light signal and transmits it through the transmission layer to the detection area of ​​the light detection unit. The light detection unit converts the received light signal into an electrical signal.

[0026] The beneficial technical effects of the present invention are:

[0027] The present invention sets a photonic crystal microstructure between the scintillator and the light detection unit, which increases the field angle of the light detection unit and greatly improves the efficiency of the scintillator fluorescence entering the light detection unit, thereby improving the sensitivity and signal-to-noise ratio of the detector. The capacitance of the detector does not increase while increasing the detection area, so it has a higher response frequency and a high-speed advantage.

[0028] The present invention also sets a transparent metal layer above the photonic crystal microstructure, which can shield high-energy particles that penetrate the scintillator, reduce radiation damage to the structure below the scintillator, make the detector performance less likely to degrade, and extend the service life of the detector. At the same time, the present invention sets a high-reflection film on the back of the substrate, which can make the light signal entering the substrate achieve internal multiplication through reflection, improve the sensitivity of the detector, and realize the detection of weak signals. BRIEF DESCRIPTION OF THE DRAWINGS

[0029] Figure 1 It is a cross-sectional schematic diagram of an embodiment of a scintillator detector having a photonic crystal microstructure.

[0030] Figure 2 It is a top view schematic diagram of an embodiment of a photonic crystal microstructure.

[0031] Figure 3-Figure 12This is a cross-sectional view of the process steps of an embodiment of a method for preparing a scintillator detector with a photonic crystal microstructure provided by the present invention, wherein:

[0032] Figure 3 It is a cross-sectional view of an embodiment of a substrate provided by the present invention.

[0033] Figure 4 It is a cross-sectional view of an embodiment of the present invention in which an N-type doping region and a P-type doping region are prepared.

[0034] Figure 5 It is a cross-sectional view of an embodiment after the first contact hole and the second contact hole are prepared in the present invention.

[0035] Figure 6 It is a cross-sectional view of an embodiment of the present invention in which the first electrode metal and the second electrode metal are prepared.

[0036] Figure 7 It is a cross-sectional view of an embodiment after the first lead-out hole and the second lead-out hole are prepared in the present invention.

[0037] Figure 8 It is a cross-sectional view of an embodiment of the present invention after preparing a high-reflective film.

[0038] Fig. 9 It is a cross-sectional view of an embodiment of the present invention after the transmission layer is prepared.

[0039] Fig.10 It is a cross-sectional view of an embodiment of the present invention after preparing the photonic crystal microstructure.

[0040] Fig.11 It is a cross-sectional view of an embodiment of the present invention in which a transparent metal layer is prepared.

[0041] Fig.12 It is a cross-sectional view of an embodiment of the scintillator prepared by the present invention.

[0042] Figure numerals: 1-scintillator, 2-transparent metal layer, 3-photonic crystal microstructure, 4-transmission layer, 51-first electrode metal, 52-second electrode metal, 6-P-type doping region, 7-N-type doping region, 8-substrate, 9-high reflective film, 10-dielectric layer, 11-passivation layer, 121-first lead-out hole, 122-second lead-out hole, 131-first contact hole, 132-second contact hole. DETAILED DESCRIPTION

[0043] The specific implementation of the present invention will be further described below in conjunction with the accompanying drawings.

[0044] A scintillator detector with a photonic crystal microstructure comprises a scintillator 1, a transmission layer 4, a photonic crystal microstructure 3 and a light detection unit, wherein:

[0045] The scintillator 1 is located above the photonic crystal microstructure 3, the photonic crystal microstructure 3 is arranged on the transmission layer 4, and the transmission layer 4 is arranged on the light detection unit;

[0046] The scintillator 1 absorbs incident particles and generates a light signal that is incident on the photonic crystal microstructure 3. The photonic crystal microstructure 3 focuses the light signal and transmits it to the detection area of ​​the light detection unit through the transmission layer 4. The light detection unit converts the received light signal into an electrical signal.

[0047] Specifically, the scintillator 1 is made of a material that can emit scintillation fluorescence after absorbing high-energy particles. The function of the scintillator 1 is to convert the incident high-energy signal into a light signal with a wavelength range of 200nm-800nm. The scintillator 1 can be an alkali metal halide scintillator, a lanthanide halide scintillator or a potassium cryolite scintillator. The transmission layer 4 is a light-transmitting material bonded to the light detection unit, and its material can be quartz glass, silicate glass, borate glass, sapphire glass or fluorite glass. The transmission layer 4 provides a transmission path for the light signal passing through the photonic crystal microstructure 3.

[0048] The photonic crystal microstructure 3 has a different refractive index from the transmission layer 4, which can change the transmission path of light to achieve a focusing function, so that the light signal converges in the detection area of ​​the light detection unit, even if the light signal can be detected by the light detection unit. The photonic crystal microstructure 3 can improve the field of view of the light detection unit, greatly improve the efficiency of the scintillator fluorescence entering the light detection unit, and increase the sensitivity and signal-to-noise ratio of the detector. The capacitance of the overall detector is not increased while increasing the detection area, so it has a higher response frequency and has the advantage of high speed. The light detection unit converts the light signal into an electrical signal to provide it to the subsequent readout circuit for measurement and processing, and obtains the energy, time and other information of the high-energy rays, thereby completing the detection of high-energy rays. The specific form of the photonic crystal microstructure 3 and the light detection unit can be referred to the following description.

[0049] Furthermore, the photonic crystal microstructure 3 is an array structure or a ring structure;

[0050] When the photonic crystal microstructure 3 is an array structure, it includes a plurality of columns distributed on the transmission layer according to a first preset period, and the horizontal cross-section of the column is circular, rectangular or regular polygonal;

[0051] When the photonic crystal microstructure 3 is a ring structure, it includes a plurality of ring bodies concentrically distributed on the transmission layer according to a second preset period, and the ring bodies are in the shape of a circular ring or an elliptical ring.

[0052] Specifically, the photonic crystal microstructure 3 is an array structure or a ring structure formed on the surface of the transmission layer 4 by etching or coating, and the material of the photonic crystal microstructure 3 can be selected from gold, platinum, aluminum, titanium dioxide, titanium nitride, silicon dioxide or silicon nitride. Figure 2 FIG. 3 shows a schematic top view of an embodiment of a photonic crystal microstructure 3 when the photonic crystal microstructure 3 is an array structure and the horizontal cross section of the columnar body is rectangular, as shown in FIG. Figure 2 As shown, the overall outline of the array structure 3 in this embodiment is rectangular, and a plurality of columns are arranged to form a grid array.

[0053] The first preset period and the second preset period are determined according to the scintillator fluorescence wavelength, that is, the period of the photonic crystal microstructure 3 is determined by the wavelength of the light signal generated by the scintillator 1. In this embodiment, the period of the photonic crystal microstructure 3 is 0.9-1.1 times the scintillator fluorescence wavelength, that is, the period is close to the scintillator fluorescence wavelength. When the photonic crystal microstructure 3 is an array structure, the period of the photonic crystal microstructure is the distance between the geometric centers of adjacent columns on the cross section. When the photonic crystal microstructure 3 is a ring structure, the central cross section of the photonic crystal microstructure will form a plurality of spaced rectangles, and at this time, the period of the photonic crystal microstructure 3 is the distance between the geometric centers of adjacent rectangles on the central cross section.

[0054] When the photonic crystal microstructure 3 is an array structure, the duty cycle of the photonic crystal microstructure 3 decreases from the center to the edge of the photonic crystal microstructure 3 on the cross section of the photonic crystal microstructure 3. When the photonic crystal microstructure 3 is a ring structure, the duty cycle of the photonic crystal microstructure 3 decreases from the center to the edge of the photonic crystal microstructure 3 on the central cross section of the photonic crystal microstructure 3. For the array structure, the duty cycle is defined as the ratio of the length of the column and the gap along the horizontal direction on the cross section of the photonic crystal microstructure 3 within one period. For the ring structure, the duty cycle is defined as the ratio of the length of the ring and the gap along the horizontal direction on the central cross section of the photonic crystal microstructure 3 within one period. Taking the array structure as an example, Fig.10 Where P represents the period length, d represents the length of the gap along the horizontal direction, Pd represents the length of the column in the horizontal direction within one period, and the duty cycle of the photonic crystal microstructure 3 within this period can be expressed as (Pd) / d, where the horizontal direction is perpendicular to the thickness direction of the transmission layer 4.

[0055] Preferably, a transparent medium is filled between adjacent columns or rings to improve the support of the photonic crystal microstructure 3 and ensure the stability of the photonic crystal microstructure 3. The transparent medium can be silicon dioxide. In specific implementation, the edge of the photonic crystal microstructure 3 is also provided with a transparent medium to form a plane with the transparent medium filled between the columns or rings.

[0056] The thickness of the transmission layer 4 is adapted to the focal length of the photonic crystal microstructure 3, that is, the thickness of the transmission layer 4 is less than or equal to the focal length of the photonic crystal microstructure 3, and it is preferable that the thickness of the transmission layer 4 is equal to the focal length of the photonic crystal microstructure 3. The focal length of the photonic crystal microstructure 3 can be determined according to the scintillator fluorescence wavelength, the period of the photonic crystal microstructure 3, and the duty cycle of the photonic crystal microstructure, and the determination method is consistent with the prior art.

[0057] Furthermore, the scintillator detector also includes a transparent metal layer 2 for preventing incident particles from entering the photonic crystal microstructure 3. The transparent metal layer 2 is prepared on the photonic crystal microstructure 3, and the material of the transparent metal layer 2 includes gold, silver, indium tin oxide or zirconium oxide.

[0058] Specifically, the transparent metal layer 2 is a dense film system plated on the surface of the photonic crystal microstructure 3, and its main function is to shield the incident high-energy particles, prevent the high-energy particles from entering the structure below the transparent metal layer 2, and reduce the radiation damage under strong radiation conditions to extend the service life of the detector. When the material of the transparent metal layer 2 is gold or silver, the thickness of the transparent metal layer 2 is preferably 4-6nm; when the material of the transparent metal layer 2 is indium tin oxide or zirconium oxide, the thickness of the transparent metal layer 2 is preferably 60nm.

[0059] Furthermore, the light detection unit includes a substrate 8 and a high-reflection film 9, wherein the substrate 8 has a front side and a back side corresponding to the front side, and the high-reflection film 9 is disposed on the back side of the substrate 8;

[0060] The high-reflective film 9 includes a plurality of stacked composite films, wherein the composite film includes at least a first refractive film and a second refractive film stacked up and down, wherein the first refractive film is stacked on the second refractive film, and the refractive index of the first refractive film is less than the refractive index of the second refractive film;

[0061] The film thickness of the first refractive film and the second refractive film is a multiple of one quarter of the peak wavelength of the scintillator fluorescence.

[0062] Specifically, the light detection unit generates an electrical signal based on the photogenerated electron-hole pairs. The high-reflection film is arranged on the back of the substrate 8 to reflect the light signal transmitted to the back of the substrate 8 back into the substrate 8, thereby increasing the number of photogenerated electron-hole pairs in the substrate 8 and realizing photomultiplication to improve the sensitivity of the detector. The material of the substrate 8 can be selected from semiconductor materials such as Si, InSb, GaN, InP, GaSb, and GaAs, and can be selected according to actual needs during specific implementation.

[0063] The high-reflection film 9 adopts a multi-layer film system, which is formed by stacking several layers of composite films to obtain a high-reflection film with a reflectivity close to 1. In this embodiment, the high-reflection film is formed by stacking multiple layers of composite films, and the composite film is formed by two layers of refractive films stacked up and down, namely a first refractive film and a second refractive film, the first refractive film is stacked on the second refractive film, and the refractive index of the first refractive film is less than the refractive index of the second refractive film, and the film thickness of the first refractive film and the second refractive film is a multiple of one quarter of the peak wavelength of the scintillator fluorescence. The refractive index of the first refractive film is relatively low, and the material of the first refractive film can be selected from SiO2, MgF2 or Al2O3. The refractive index of the second refractive film is relatively high, and the material of the second refractive film can be selected from ZrO2, NbO5, TiO2, ZnO or HfO2.

[0064] Furthermore, the light detection unit further includes an N-type doping region 7, a P-type doping region 6, a dielectric layer 10 and a metal layer, wherein the metal layer includes a first electrode metal 51 and a second electrode metal 52, wherein:

[0065] The N-type doping region 7 and the P-type doping region 6 are arranged in the substrate 8 and isolated by the substrate 8. The dielectric layer 10 is prepared on the front side of the substrate 8. The first electrode metal 51 and the second electrode metal 52 are supported on the dielectric layer 10, and the first electrode metal 51 and the second electrode metal 52 are spaced apart from each other.

[0066] The first electrode metal 51 is in ohmic contact with the P-type doping region 6 , and the second electrode metal 52 is in ohmic contact with the N-type doping region 7 .

[0067] Specifically, the area of ​​the substrate 8 corresponding to the area formed by the interval between the first electrode metal 51 and the second electrode metal 52 is the detection area of ​​the light detection unit, and the N-type doping area 7 and the P-type doping area 6 constitute a field effect transistor. In specific implementation, a PN junction diode, a PIN junction diode, an avalanche diode, etc. can also be formed in the substrate 8 by setting different doping areas. When the light signal is incident on the detection area, the substrate 8 generates photogenerated hole-electron pairs, and the photogenerated hole-electron pairs form a conductive channel between the N-type doping area 7 and the P-type doping area 6, so that the N-type doping area 7 and the P-type doping area 6 are connected to generate current and form an electrical signal.

[0068] The horizontal length of the transmission layer 4 is smaller than the horizontal length of the substrate 8, so as to facilitate the extraction of the potentials of the first electrode metal 51 and the second electrode metal 52. A passivation layer 11 is prepared on the metal layer, and the passivation layer 11 is provided with a first extraction hole 121 and a second extraction hole 122. The first extraction hole 121 and the second extraction hole 122 are respectively located on both sides of the transmission layer 4, and the first extraction hole 121 is located above the first electrode metal 51, and the second extraction hole 122 is located above the second electrode metal 52. The electrical signal is extracted to the reading circuit through the first extraction hole 121 and the second extraction hole 122, and the form of the reading circuit can be consistent with the prior art.

[0069] For the above-mentioned scintillator detector having the photonic crystal microstructure 3, the present invention provides a method for preparing the scintillator detector having the photonic crystal microstructure 3, and the method for preparing the scintillator detector having the photonic crystal microstructure 3 comprises:

[0070] A light detection unit is prepared, a transmission layer 4 is prepared on the light detection unit, and a photonic crystal microstructure 3 and a scintillator 1 are prepared on the transmission layer 4, wherein the scintillator 1 is located above the photonic crystal microstructure 3; the scintillator 1 absorbs incident particles and generates a light signal incident on the photonic crystal microstructure 3, the photonic crystal microstructure 3 focuses the light signal and transmits it through the transmission layer 4 to a detection area of ​​the light detection unit, and the light detection unit converts the received light signal into an electrical signal.

[0071] Figure 3-Figure 12 An embodiment of the process steps for preparing the scintillator detector having the photonic crystal microstructure 3 is shown below. Figure 3-Figure 12 The process of specific process steps is described in detail.

[0072] like Figure 3-Figure 4 As shown, a substrate 8 is provided. For the provided substrate 8, a cleaning process is generally required to achieve the purpose of cleaning. After cleaning, a photoresist is coated on the front of the substrate 8 and patterned to obtain two injection windows in the target doping area. The photoresist can be coated on the substrate layer 8 using the commonly used technical means in the technical field, and the model of the photoresist can be selected as needed to meet the process requirements. The two injection windows are used to implant N-type doping ions and P-type doping ions into the substrate 8, and high-temperature annealing is performed after the injection is completed to form a P-type doping area 6 and an N-type doping area 7. During specific implementation, the ion implantation energy and dosage can be adjusted according to the process level conditions, so as to achieve an implantation depth greater than 500nm. The temperature and time of annealing can also be selected as needed to eliminate lattice damage.

[0073] like Figure 5As shown, silicon dioxide is deposited on the front side of the substrate 8 and planarized to prepare a dielectric layer 10 , and a first contact hole 131 located above the P-type doped region 6 and a second contact hole 132 located above the N-type doped region 7 are etched on the dielectric layer 10 .

[0074] like Figure 6 As shown, a photoresist is coated on the front of the substrate 8 and a mask is formed by a reverse photolithography process. A 1 μm thick aluminum-copper metal is sputtered on the substrate 8 with the mask and peeled off. The alloy is formed by rapid annealing by an RTA process to form a first electrode metal 51 and a second electrode metal 52. The first electrode metal 51 is partially located in the first contact hole 131, and the first electrode metal 51 is used to make an ohmic contact with the P-type doping region 6 by using the first electrode metal 51 located in the first contact hole 131. The second electrode metal 52 is partially located in the second contact hole 132, and the second electrode metal 52 is used to make an ohmic contact with the N-type doping region 7 by using the second electrode metal 52 located in the second contact hole 132.

[0075] like Figure 7 As shown, silicon nitride is deposited on the front side of the substrate 8 where the first electrode metal 51 and the second electrode metal 52 are formed and planarized to form a passivation layer 11. The passivation layer 11 is photolithographically etched above the first electrode metal 51 to obtain a first lead-out hole 121, and above the second electrode metal 52 to obtain a second lead-out hole 122.

[0076] like Figure 8 As shown, low refractive index material SiO2 and high refractive index material ZrO2 are repeatedly and alternately chemically deposited on the back of substrate 8 to form a total of 10 layers of refractive film. The deposition starts with low refractive index material and ends with high refractive index material to form a high reflective film.

[0077] like Fig. 9 As shown, a transmission layer 4 is prepared by bonding SiO2 to the front side of the substrate 8 by a first optical coupling agent. It should be noted that, since the photonic crystal microstructure 3 in this embodiment is obtained by etching on the surface of the transmission layer 4, in order to make the thickness of the transmission layer 4 after removing the photonic crystal microstructure 3 after etching equal to the focal length of the photonic crystal microstructure 3, at this time, the thickness of the transmission layer 4 is the sum of the thickness of the photonic crystal microstructure 3 and its focal length, the first optical coupling agent can select a coupling silicone oil with a refractive index close to the refractive index of the transmission layer 4, and the thickness of the first optical coupling agent can be 80nm.

[0078] like Fig.10 As shown, the surface of the transmission layer 4 is aligned by double-sided overlay in the photolithography process, and the photonic crystal microstructure 3 is prepared by photolithography and dry etching. Silicon dioxide is deposited on the surface of the transmission layer 4 with the prepared photonic crystal microstructure 3 and planarized.

[0079] like Fig.11As shown, indium tin oxide or zirconium oxide with a thickness of 60 nm is magnetron sputtered on the photonic crystal microstructure 3 , or gold or silver with a thickness of 4 nm is magnetron sputtered to form a transparent metal layer 2 .

[0080] like Fig.12 As shown, the scintillator 1 is attached to the surface of the transparent metal layer 2 through a second optical coupling agent. The material of the scintillator 1 can be CsI, CdWO4, GOS, ZnSe or YAG. The second optical coupling agent can be a coupling silicone oil with a refractive index of 1.8 and a thickness of 80nm.

[0081] It should be noted that the words "front", "rear", "left", "right", "upper" and "lower" used in the above description refer to directions in the drawings of the present application specification, and the words "front" and "back", "inner" and "outer" refer to directions toward or away from a specific component, respectively. In addition, the terms "first" and "second" are used for descriptive purposes only and cannot be understood as indicating or implying relative importance or implicitly indicating the number of the indicated technical features.

[0082] The above is only a preferred embodiment of the present invention, and the present invention is not limited to the above embodiments. It is understood that other improvements and changes directly derived or associated by those skilled in the art without departing from the spirit and concept of the present invention should be considered to be included in the protection scope of the present invention.

Claims

1. A scintillator detector having a photonic crystal microstructure, characterized in that: It includes a scintillator, a transmission layer, a photonic crystal microstructure and a light detection unit, wherein: The scintillator is located above the photonic crystal microstructure, the photonic crystal microstructure is arranged on the transmission layer, and the transmission layer is arranged on the light detection unit; The scintillator absorbs incident particles and generates a light signal that is incident on the photonic crystal microstructure. The photonic crystal microstructure focuses the light signal and transmits it through the transmission layer to the detection area of ​​the light detection unit. The light detection unit converts the received light signal into an electrical signal.

2. The scintillator detector with a photonic crystal microstructure according to claim 1, characterized in that: The photonic crystal microstructure is an array structure or a ring structure; When the photonic crystal microstructure is an array structure, it includes a plurality of columns distributed on the transmission layer according to a first preset period, and the horizontal cross-section of the column is circular, rectangular or regular polygonal; When the photonic crystal microstructure is a ring structure, it includes a plurality of ring bodies concentrically distributed on the transmission layer according to a second preset period, and the ring bodies are in the shape of a circular ring or an elliptical ring.

3. The scintillator detector with a photonic crystal microstructure according to claim 2, characterized in that: When the photonic crystal microstructure is an array structure, on a cross section of the photonic crystal microstructure, the duty cycle of the photonic crystal microstructure decreases from the center to the edge of the photonic crystal microstructure; When the photonic crystal microstructure is a ring-shaped structure, on the central cross-section of the photonic crystal microstructure, the duty cycle of the photonic crystal microstructure decreases from the center to the edge of the photonic crystal microstructure.

4. The scintillator detector with a photonic crystal microstructure according to claim 2, characterized in that: A transparent medium for improving the support of the photonic crystal microstructure is filled between adjacent columns and rings, and the first preset period and the second preset period are determined according to the scintillator fluorescence wavelength.

5. The scintillator detector with a photonic crystal microstructure according to claim 1, characterized in that: The thickness of the transmission layer is adapted to the focal length of the photonic crystal microstructure, and the refractive index of the transmission layer is different from the refractive index of the photonic crystal microstructure.

6. The scintillator detector with a photonic crystal microstructure according to claim 1, characterized in that: It also includes a transparent metal layer for preventing incident particles from entering the photonic crystal microstructure. The transparent metal layer is prepared on the photonic crystal microstructure, and the material of the transparent metal layer includes gold, silver, indium tin oxide or zirconium oxide.

7. The scintillator detector with a photonic crystal microstructure according to claim 1, characterized in that: The light detection unit comprises a substrate and a high-reflection film, wherein the substrate has a front side and a back side corresponding to the front side, and the high-reflection film is arranged on the back side of the substrate; The high-reflective film comprises a plurality of stacked composite films, wherein the composite film comprises at least a first refractive film and a second refractive film stacked up and down, wherein the first refractive film is stacked on the second refractive film, and the refractive index of the first refractive film is less than the refractive index of the second refractive film; The film thickness of the first refractive film and the second refractive film is a multiple of one quarter of the peak wavelength of the scintillator fluorescence.

8. The scintillator detector with a photonic crystal microstructure according to claim 6, characterized in that: The light detection unit further includes an N-type doping region, a P-type doping region, a dielectric layer and a metal layer, wherein the metal layer includes a first electrode metal and a second electrode metal, wherein: The N-type doping region and the P-type doping region are arranged in the substrate and isolated by the substrate, the dielectric layer is prepared on the front side of the substrate, the first electrode metal and the second electrode metal are supported on the dielectric layer, and the first electrode metal and the second electrode metal are spaced apart; The first electrode metal is in ohmic contact with the P-type doping region, and the second electrode metal is in ohmic contact with the N-type doping region.

9. The scintillator detector with a photonic crystal microstructure according to claim 8, characterized in that: A passivation layer is prepared on the metal layer. The passivation layer is provided with a first lead-out hole and a second lead-out hole. The first lead-out hole is located above the first electrode metal, and the second lead-out hole is located above the second electrode metal.

10. A method for preparing a scintillator detector having a photonic crystal microstructure, characterized in that: Used to prepare a scintillator detector having a photonic crystal microstructure according to any one of claims 1 to 9, the preparation method comprising: Prepare a light detection unit, prepare a transmission layer on the light detection unit, and prepare a photonic crystal microstructure and a scintillator on the transmission layer, wherein the scintillator is located above the photonic crystal microstructure; The scintillator absorbs incident particles and generates a light signal that is incident on the photonic crystal microstructure. The photonic crystal microstructure focuses the light signal and transmits it through the transmission layer to the detection area of ​​the light detection unit. The light detection unit converts the received light signal into an electrical signal.

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