New UV camera devices and applications

    Abstract: New ultraviolet technology is another new detection technology developed after laser detection technology and infrared detection technology. Therefore, the development and research of ultraviolet technology and ultraviolet imaging devices are of extremely important significance to modern national defense and people's lives. This article focuses on the development level and application fields of three types of ultraviolet devices, and focuses on the application of SiC, GaN ultraviolet detectors, ultraviolet CCDs, ultraviolet cameras, and ultraviolet digital cameras in national defense and other fields. detailed introduction.

    Keywords: UV detector UV CCD UV camera digital camera

1 Introduction

As early as the 1950s, people began research on ultraviolet detection technology. Ultraviolet detection technology is a dual-use photoelectric detection technology developed after infrared and laser detection technology. Ultraviolet detection technology has been widely used in medicine, biology and other fields, especially in the diagnosis of skin diseases in recent years. Using ultraviolet detection technology, you can directly see the details of the lesions when detecting and diagnosing skin diseases. It can also be used to detect cancer cells, microorganisms, hemoglobin, white blood cells, red blood cells, cell nuclei, etc. The level detection is not only fast and accurate, but also intuitive and clear. However, due to the low sensitivity of electronic devices, they have not been widely used. It was not until the 1990s that Japan developed the Avalanche Multiplying Target (HARP) camera tube, which enabled ultraviolet imaging devices to obtain higher sensitivity and a more suitable spectral range, and therefore ultraviolet imaging devices were widely used.

Since the HARP target camera tube itself is large in size, has high power consumption and high working voltage, the UV imaging system assembled from it is also large in size, has high power consumption and high cost, thus limiting the application of the UV imaging system. Based on this situation, in the field of ultraviolet detection technology, people have been developing and researching solid-state ultraviolet imaging devices such as ultraviolet detectors, ultraviolet sensors, and ultraviolet CCDs that can meet application needs, and have made great progress. In the military, it is mainly used in ultraviolet warning, ultraviolet communication, ultraviolet/infrared composite guidance and missile detection.

2 UV detection devices

2.1 UV detector

a.SiC UV detector

This product is a SiC photoexcited UV detector. Because it only selectively absorbs light with wavelengths above 40nm, it does not require protective filters for visible light or near-infrared light. Compared with silicon detectors, its ultraviolet light absorption is two orders of magnitude greater and does not require surface processing. processing to maintain long-term stability. In addition, the sensitivity and dark current are almost not affected by temperature changes within the operating temperature conditions, and can be used at high temperatures of 700K.

b.GaN-based UV detector

Since the GaN material has a very sharp cut-off response characteristic in the 365nm (ultraviolet) band, it reduces the requirements for filters, which makes the GaN-based photodetector capable of detecting ultraviolet light without being affected by long-wavelength radiation. The band monitors the characteristics of the Solar Blind area. At present, the American APA Optical Company has produced this new device using GaN Schottky diodes on a sapphire substrate.

Applications for GaN-based UV detectors include flame sensing, ozone monitoring, blood analyzers, mercury lamp disinfection control, laser detectors and other applications that require solar blind zone characteristics.

2.2 UV sensor

In early 1999, the Colorado Health Care Devices Company in the United States launched a sensor that can accurately measure the sun's ultraviolet rays and has put it on the market.

The sensor is equipped with two scales, one is used to display the skin type of the sunbather, because different skin types have different radiation resistance; the other scale is used to display the skin care index, that is, the sunscreen device used by the sunbather. Performance index. Using this sensor, it is possible to measure the intensity of the sun's UV rays and the safe amount of exposure to the skin or bathrobe, as well as the duration of the sun exposure. The system can enable sunbathers to measure the degree of ultraviolet radiation to the skin on the spot and tell people when the sun is most suitable for sunbathing.

In 1999, Japan's Osaka Gas Company prepared a low-intensity ultraviolet photodetector on MOVPEE-grown AlxGal-xN. Metal-semiconductor-metal (MSM) detectors prepared on low dislocation density layers (6 × 10 7 ~ 1 × 10 9 cm -2) can display very low dark current (less than 50 fA at 10 V) and exhibit excellent performance in UV An attenuation ratio of three orders of magnitude was obtained between it and visible light, and its cut-off wavelengths were 365nm and 270nm when X=0 and X=0.43, respectively. In addition, the company has also developed AlGaN ultraviolet (365nm) photodiode arrays using AlGaN.

2.3 UV CCD

Generally, the wavelength range of ultraviolet radiation is 100nm ~ 400nm. The absorption coefficient of ultraviolet (UV) photons in silicon is very high. Since CCD is a MOS structure device, both SiO2 gate dielectric and polysilicon (Poly-Si) gate have high absorption coefficients for UV photons. Therefore, it is very difficult to use CCD for UV photon detection because UV photons can hardly reach the silicon substrate.

In order to avoid UV photons being absorbed in the multi-layer structure of the CCD surface, the current method is:

(1) Deposit a layer of phosphorescent properties sensitive to UV photons on the surface of the CCD, and convert the ultraviolet information into a wavelength corresponding to the CCD spectral response by appropriately selecting the phosphorescent material. This phosphorescent substance can be corona benzene. When excited by ultraviolet radiation with a wavelength less than 0.4μm (400nm), coronene emits fluorescence with a peak value close to 500nm in the green light band of the visible spectrum. The spectral response of the CCD before and after covering corona benzene is shown in Figure 1;

(2) Using the backside irradiation method, to form the generation and collection areas of charge carriers, the CCD substrate must be thinned. The typical thickness after thinning is about 10 μm. Of course, the thinning process and subsequent fine processing increase the difficulty of production, but it is worth it for UV detection. A major surface challenge caused by backside thinning is that there is often a high concentration of recombination centers on the etched surface of the silicon. UV photons are absorbed at the surface near the silicon backside to create electron-hole pairs. Many photoelectrons are recombined before being collected on the front of the CCD. In order to solve this problem, an additional electric field can be generated by injecting a very shallow P layer on the back of the thinned CCD to drive the photogenerated electrons to the front without being recombined. Of course, further high-temperature treatment after implantation is detrimental to the device, but it can be solved by rapid laser annealing;

(3) Use deep depletion CCD method. Using a lightly doped, high-resistivity substrate, the depletion region under the CCD gate is extended to the back of the silicon wafer. Electrons generated by UV photons incident on the back are swept into the front by the electric field in the depletion region. This deep depletion CCD method not only avoids polysilicon gate absorption, but also avoids the necessary thinning of conventional doping concentration back-illuminated CCDs. Another advantage of the depletion method is that high-temperature processes can be performed after the silicon wafer and a wide variety of passivation structures can be obtained.

Figure 1 shows the spectral response before and after depositing phosphor on the CCD surface.

Figure 2 shows the cross-sectional structure of a deep depletion CCD. The P+ layer injected on the backside can improve the characteristics of the CCD backside by reducing device dark current and increasing quantum efficiency. The thickness of this deep depletion CCD substrate is approximately 150μm, and the resistivity is 4kΩ.cm~10kΩ.cm.

The disadvantage of the deep depletion CCD method is the long dark current, which increases linearly with the volume of the space charge region. The dark current is large at room temperature, but the dark current will decrease significantly as the temperature decreases. For UV applications in most disciplines, cooling is easily achieved and dark current is no longer an issue.

Ultraviolet CCD is a silicon CCD that is thinned and then coated with fluorescent material to couple ultraviolet light into the device. It allows the device to have the ability to take pictures in the wavelength range from vacuum ultraviolet to near-infrared. In 1997, NASA successfully developed a novel 256×256 pixel GaN ultraviolet CCD. It is a hybrid ultraviolet CCD formed by flip-chip interconnecting GaN ultraviolet detectors and silicon CCD multiplexers through indium pillars. From the perspective of development trends, with the continuous improvement of GaN, SiC and AlGaN ultraviolet detector technology, GaN, SiC and AlGaN ultraviolet CCD will be the main development direction of ultraviolet imaging devices in the future. It will be widely used in both military and civilian fields, especially in military applications (such as ultraviolet warning, ultraviolet communication, ultraviolet/infrared composite guidance, etc.), which will attract great attention from the military.

紫外CCD摄像机是以δ(delta)掺杂CCD技术为基础的，它包括一个2.5nm厚的硅掺杂层，该掺杂层用分子束外延（MBE）生长在一个薄的CCD背面，δ掺杂能增强对由紫外光子照射产生的电子的探测能力，效率几乎可达200%，为增强0.3～0.7μm的灵敏度，可在传感器阵列涂上抗反射涂层，这样可使激活区的画面传递达到256×512像元，有效速度为30帧/秒，为便于摄像机操作，其中还可装入实用的电子部件。

1998年，日本滨板公司开发成功了新型紫外固体摄像器件—薄型背照式电荷耦合器件（BT—CCD=Back Thinned Charge Coupled Device），由于采用了特殊的制造工艺和特殊的锁相技术，该BTCD不仅具有固体摄像器件的一般优点，而且具有噪声低，灵敏度高、动态范围大的优点。

BTCCD是一种薄型背照式摄像器件，它主要由三部分组成：垂直CCD移位寄存器，水平CCD移位寄存器和锁定放大器。在时钟脉冲驱动下，信号电荷由垂直CCD移位寄存器一步一步地输送到水平CCD移位寄存器，再由锁相（定）放大器变换成电压信号输出。其框图如图3所示。

其中锁相放大器作用较重要，它有很高的电荷—电压变换灵敏度和很低的噪声，因而它的信噪比和灵敏度都很高。

BTCCD有很高的紫外光灵敏度，它在紫外波段的量子效率如图4所示。从图中可以看到，在紫外波段，量子效率超过40%，可见光部分超过80%，甚至可以达到90%左右。可见，BTCCD不仅可工作于紫外光，也可工作于可光。因此BTCCD是一种很优秀的宽波段摄像器件。

BTCCD之所以有很高的灵敏度，这主要是由其结构特点决定的。首先，与FI-CCD相比，硅层厚度从数百微米减薄到20μm以下；其次，它采用背照射结构，因此紫外光不必再穿越钝化层。

另外，滨松公司又开发出MOS（Metal Oxide Semiconductor）摄像器件，这种紫外线MOS摄像器件的结构比较简单，制造也相对容易。它的量子效率如图5所示。它在紫外区的量子效率可达30%，并有较高的紫外光灵敏度。

BTCCD摄像器和MOS摄像器的比较如表1所列。从表1看到，BTCCD确有很高的性能。

表1 BT-CCD和MOS摄像器的比较

2.4 紫外成像器件

由于硅在200～400nm波段内的吸收深度小，因此在紫外波段内进行成像比较困难。然而现在人们已经找到能够达到良好紫外响应的许多方法，Photometrics公司采用在正面照射的CCD上加一辐射转换成普通CCD能够响应的中等波长的可见光而不需要对硅本射作专门的处理。在这种情况下，正面照射的CCD在200～400nm的波段内可达到20%的量子效率。

如再经过适当背面注入处理，涂有特制抗反射涂料并且具有深耗尽层的背面照射CCD在200～400nm波段内可达到50%以上的量子效率。在喷气推进实验中首次推出的金属闪光栅可用来代替背照射CCD的注入后经退火的背面。另一种方法是在薄型CCD背面放置一发光层，这同正面照射方法相似，但量子效率却比较高。

目前Sarnoff研究中心的紫外研究工作有两个方向：第一个方向是研制线阵和隔行转移列阵格式的CMOS/CCD。现已证明，这种方法所产生的探测器随着时间和表面电荷的变化能保持高度的稳定性；第二个方向是为海洋研究公室研究一种薄型背面照射技术，模拟证明，这种技术可以在深真空紫外波段（10nm）获得30%以上的稳定量子效率，并可研制出大规模CCD。在真空紫外以下，硅CCD已可用来在远紫外（10～100nm）和软X射线（0.1～10nm）波段内成像。

2.5 GaN紫外摄像机

对于各种应用来说（从跟踪导弹发射到研究远距离星体），能观察紫外线是很有用的。然而以硅为基础的探测器不是捕获紫外线的最好办法。为了改进这一技术，北卡罗来纳大学的研究人员与美国陆军夜视实验室合作研制了一种以GaN为基础的可见光盲紫外摄像机。

这种摄像机包含一个32×32GaN/AlGaN异质结PIN光电二极管阵列。底层为n掺杂的GaN，具有接近20%的Al,其上是一层非掺杂的GaN层，再上是一层P掺杂的GaN层。整个结构建立在一个光能穿过的抛光的蓝宝石基底上。每一个光电二极管都对320nm～365nm的光波具有敏感的响应。波长小于320nm的光被AlGaN底层吸收，波长长于365nm的光穿过GaN。增加底层和顶层Al的含量可改变光电二极管的带宽。

由于紫外摄像机的潜在国防应用前景，这项工作获得了陆军研究办公室和国防高级研究项目的资助。该项工作的参加者还包括哈尼维尔技术中心的研究人员。军事应用希望太阳盲式紫外探测器能在250nm～280nm波段成像，这样依能跟踪导弹的载入而不为太阳光所干扰。Schetzina说：“我们还没有作到这一点，这将是下一步的事”。

1999年美国北卡罗来纳州立大学夜视实验室和霍尼威尔技术中心研制出1024像元的AlGaN紫外光电二极管阵列，该阵列响应波长为365nm，目前，他们已用该阵列组装成数字紫外摄像机。

另外，美国纽约州的COOK公司也向市场提供了Dicam-pro型增强式制冷型CCD相机，它的曝光时间很短，仅3ns。CCD相机的像元数为1280×1024元，并具有12bit的动态范围。其工作波段位于近红外-紫外波段。这种相机可用于荧光分析，化学荧光分析、光谱分析、弹道分析、生物荧光分析、高速流体分析、电源现象分析以及PIV成像等系统。可用光缆传输从相机到PCI接口板的串行数据。

2.6 紫外CCD摄像机

a.紫外/X光CCD摄像机

APP公司与CEA公司合作，研制出一种称为ANIMATERV3X的数字成像系统，该系统的灵敏度为数电子伏至数千电子伏。它采用的是512×512元的高分辨率传感（TH7895A），这是一种背面照射的薄型CCD传感器，其敏感波段可延伸至短紫外和软X射线区域。入射辐射可直接照在CCD器件，产生的信息在摄像机头部经数字化处理后，通过光纤可传送给接口卡。ANIMATERV3V的最大优点是能够在紫外和X光段内成像。

b.紫外数字照相机

日益普及的数字照相机现在又迎来了一个表的家庭成员，美国一些科学家发有了可以感应紫外光的数字照相机。

由于紫外光的波长比可见光短，因而它又叫做“黑光”，因为它可以引起某些材料在黑暗中发光。一般的数字照相机只能“看见”人们内眼所看见的可见光（有时称为“白光”），但许多物体（如星球、生化武器）所发出的紫外光是普通的数字照相机所不能看到的。

北卡罗来纳州立大学固体物理实验室的物理学家Jan F.Schetzina表示，这个发明对拓展数字照相机的使用范围有很大的促进作用。

这项研究由美国陆军研究办公室和国防部高级研究项目管理局提供资金，这种照相机显然在军事上很有用，但它也可以用于医学领域，如发现早期皮肤癌等。这种照相机的工作原理与其它普通的数字照相机相类似，不同之处在于它使用AlGaN化合物来作为感光物质，而不是使用传统的硅作为感光物质。

c.紫外摄像用PtSi-SBIRFPA技术

1990年麻省理工学院林肯实验室研制成功了160×244元硅化铂肖特基势垒红外CCD（Ptsi-SBITCCD），它的像元尺寸为40×80μm2；填充系数为39%；探测器的有效面积为25×50μm2。紫外、可见光和红外光子产生的电子在PtSi电极积累后转移到埋沟CCD沟道。电荷转移控制由施加到CCD转移栅上的三电平时钟信号控制。Al光掩蔽层用于阻止CCD沟道和转移栅中因更大带隙辐射而产生的载流子。

1998年日本滨松光电子公司固体事业部采用芯片背面减薄技术成功的制作了紫外光谱区摄像应用PtSi-SBIRFPA,其瑾为S7030、S7031和S7032系列。

S7030、S7031和S7032系列产品具有低噪声和高灵敏度的特点，是紫外区的高灵敏度器件，比世界同类器件从紫外到可见光区的量子效率要高1倍，同时动态范围并可多相位驱动。偈元数为1024×256元、512×128元、512×64元，最大读出频率为1MHz；转移效率99.995%；功耗为15mW；暗电流为200个电子/像元·秒（℃C，CMMP驱动时）；在5～6℃时，其暗电流将降低到原来1/2，它的敏感波长为120～200nm，量子效率大于50%。

3 紫外器件的主要应用

3.1 导弱探测新技术

美国国防高级研究计划局正在资助开发一种紫外线感应材料技术，这种技术有望把导弹预警系统发出的错误警报降低到最低限度，并减少传感器的复杂性和成本。

目前使用的AAR-57和AAR-54等被动式导弹预警系统必须设法区分由来袭导弹发出的紫 外线和诸如太阳等无威胁的紫外线源。

据国防高级研究计划局负责这种技术研究的埃德加·马丁内斯说，这项研究旨在开发出一种诸如铝镓氮（AlGaN）的新型探测材料，它对火箭发动机发出的、太阳射线中没有的一种窄波段紫外线波长非常敏感。这种技术将使导弱预警系统能够探测出从上方飞来的导弹，并使探测紫外线的导弹预警系统更加有效地为地面武器系统预警。

目前，已有十多所大学和半导体研究机构获得了国防高级研究计划局这项耗资600万美元的研究合同。工程师们预计，这种新材料将大大增加导弹的探测范围，并降低传感器的成本。

3.2 军事紫外领域

a.紫外制导

尽管红外制导是目前导弹的主流制导方式，但随着红外对抗技术的日趋成熟，红外制导导弹的功效将受到严重威胁。为了反红外对抗技术，制导技术正在向双色制导方面发展，这其中也包括红外-紫外双色制导方式。在受到敌方红外干扰时，仍可使用紫外探测器探测目标的紫外辐射，并把导弹导引至目标以进行攻击。据报道，美国及北约盟军的陆海军在1989年装备使用的尾刺（Stinger Post）对空导弹中就采用了这种红外-紫外双色制导技术。美国研制的这种导弹就利用了红外/紫外双色制导技术，白天飞机反射的日光的紫外波段功率很强，则用紫外波段跟踪目标。夜晚紫外波段辐射功率小于红外辐射，则自动切换成红外波段跟踪目标。美国的“毒剌”导弹就采用紫外/红外复合寻的器，法国的“西北风”导弹也采用多元红外/紫外复合寻的制导方式。

b.紫外告警

为了对付导弹的威胁，导弹入侵报警器是必要的设备。目前的导弹入侵报警方式主要采用雷达工作的主动式报警和包括红外、激光和紫外告警为主的被动式报警。

紫外告警探测器是通过探测导弹尾焰中的紫外线辐射来探测目标的。表2列出了低空时使用不同燃料的导弹的尾焰辐射特征。可以看出，任何尾焰中都含有近紫外（NUV）和中紫外（MUV）线，这为紫外导弹告警提供了可能，国外已研制成功了多种紫外报警器。美国洛拉尔公司在1998年就为美国海军的C-1305直升机和P-3S运输机研制成世界上第一台新型的AAR-47紫外告警系统，它在太阳光的中紫外盲区内探测导弹羽烟的紫外辐射，从而解决了红外告警系统的虚告警问题，并很快装备了美军。在1991年海湾战争中投入实战后，又改进为AAR-47A和AAR-47B。美国西屋公司在美国海军的资助下也研制出PMAWS-2000紫外报警器，主要装备在各种战斗机，坦克和装甲车上。在1993年到1994年末，美国海军对PMAWS-2000进行了实验。紫外告警系统在问世不到10年的时间内就发展了两代产品十余种型号，从而迅速成为机载导弹逼近告警系统的重点发展方向。

表2 低空（5km以下）火箭尾焰的特征辐射

紫外告警系统最显著的特点是将响应波段置于太阳光的中紫外盲区，由于在这个波段内几乎没有自然光辐射，因而背景噪声非常小，从而减轻了信号处理的负担，使得紫外告警系统能将虚告警率控制在很低的程度。目前，美国研制的第一代紫外型导弹逼近告警系统是以光电倍增管为探测器的；而第二代紫外型导弹逼近告警系统（MAWS）则以多元或面阵器件为核心探则器。

Ultraviolet alarm uses the ultraviolet band of the "solar spectrum blind zone" to detect missile flames and plumes. Since it is insensitive to sunlight and ordinary light, it has a low false alarm rate; at the same time, it does not require low-temperature cooling and does not scan. Small size and light weight. Therefore, UV warning is increasingly gaining favor with its unique advantages and plays an extremely important role in the development of Missile Approach Warning System (MAWS). With the continuous improvement of UV sensor technology. The ultraviolet warning system will provide a more effective means for missile warning.

c.UV interference

The emergence of infrared/ultraviolet dual-color guided missiles will inevitably lead to the development of infrared/ultraviolet dual-color interference technology. The key to ultraviolet interference is the development of interference bombs with strong enough ultraviolet radiation and the addition of gunpowder with ultraviolet interference capabilities.

d.UV communication

Ultraviolet communication is a new communication method with great development potential. It has many advantages that other conventional communication methods do not have, such as low eavesdropping rate, high anti-interference, low bit resolution, all-weather operation, etc. Therefore, it has been widely valued by departments with high requirements for communication confidentiality and mobility.

The United States has significant investments in the development of ultraviolet communication systems. In the United States, a low-power ultraviolet communication system was developed in the early 1990s. At present, the finished product of the ultraviolet communication system has appeared, and this technology has been successfully applied to secret communications between space vehicles and satellites, as well as between naval warships and warships. Liaison with carrier-based aircraft, etc.

e. Ultraviolet detection technology

There are many UV detection methods, which can be roughly divided into three categories. As listed in Table 3, the key issues of UV detection technology are as follows:

Table 3 List of UV detection methods

(1) Establishment of ultraviolet atmospheric transmission theory and scattering model

The establishment of ultraviolet atmospheric transmission theory and scattering model and simulation system is one of the key issues. In many UV application fields, especially military applications, whether it is active "UV communication" and "UV interference" or passive "UV guidance" and "UV alarm", they all involve the problem of UV transmission in the atmosphere. At present, most people's attention in China is focused on the research on the characteristics of visible light and infrared radiation and their atmospheric transmission characteristics. There are few studies on UV transmission properties. In addition, ultraviolet transmission involves multiple scattering, which is an extremely complex problem. Therefore, the research on the above content has become one of the key issues in ultraviolet detection and application technology.

(2) Development of high-sensitivity ultraviolet detection devices

The development of high-sensitivity, low-noise UV detection devices is another key to UV detection technology. Currently, there are several types of UV detectors: UV vacuum diodes, discrete UV photomultiplier tubes (UV-PMT), imaging UV variable tubes, UV intensifiers, and UV camera tubes. The new one is the photomultiplier tube with microchannel (MCP-PMT), which has the characteristics of fast response speed, strong resistance to magnetic field interference, small size, light weight and simple power supply circuit. At present, close-fit focusing ultraviolet variable tubes and intensifiers with MCP structures and corresponding self-scanning arrays have also appeared, and are used in ultraviolet detection satellites, space defense, and rocket-guided weak tail flame ultraviolet detection. aspect.

In addition, there are also developments in solid-state ultraviolet detection devices. Currently, enhanced silicon photodiodes, GaAsP and GaP-coated ultraviolet solid-state devices, GaN ultraviolet detectors, ultraviolet CCD (UV-CCD) and other devices are under development and research.

(3) Low noise information processing system

The formation of a low-noise information processing system is another key issue in ultraviolet detection technology. The UV detection system is generally a weak signal receiving and processing system; it often goes through processes such as signal collection, photoelectric conversion and amplification, modulation and demodulation, and encoding and decoding. In particular, the problems of interference and noise removal are particularly prominent. For noise coming from many aspects (such as thermal noise, shot noise, low-frequency noise, amplifier noise, etc.), effective processing (such as correlation processing, lock-in amplification, signal averaging, adaptive noise cancellation, low-noise preamplification, etc.) must be carried out. Suppress external interference such as electromagnetic induction and electrostatic induction) to reduce noise and improve the system signal-to-noise ratio. Single photon counting is a very effective detection technology for extremely weak light detection, and people often use this method to solve ultraviolet detection problems.

In addition, in the civilian product market, UV detectors are also widely used. As far as the ultraviolet image intensifier tube is concerned, the imager composed of it as the core component is extremely useful in the public security criminal investigation department. For example: at a criminal crime scene, the imager can be used to observe the contrast-enhanced colorless sweat fingerprints left by criminals on non-permeable smooth surfaces such as ceramics, waxed floors, painted furniture surfaces, photographs and other special surfaces. ; If an external monitor is connected, it can be used to capture useful information in customs, archaeology, environmental protection and other fields. In addition, photomultiplier tubes and other devices will also be widely used in many fields such as biomedicine, astronomical research, synchrotron radiation, spectral analysis, particle detection, and flash photography.

4 Conclusion

Ultraviolet detection technology is another novel detection technology developed after laser depth detection technology and infrared detection technology. In UV detection technology, there are mainly UV detectors and UV camera devices. This technology has developed rapidly in recent years. So far, UV MOS image sensors, GaN/AlGaN heterojunction PIN photodiode arrays, SiC, GaN UV Detectors, UV CCD and BT-CCD PtSi-SBIRF-PA for UV imaging, etc. The reason why the research progress of ultraviolet CCD is slower than that of visible light and infrared CCD is because many problems about the interaction between ultraviolet radiation and materials used in semiconductor process have not been solved in previous years, but as the research work continues to deepen, especially The advent of GaN/AlGaN heterojunction PIN photodiode arrays in recent years will accelerate the development of GaN/AlGaN ultraviolet imaging devices and will eventually become a leader in the field of ultraviolet detection technology. Ultraviolet detection technology is one of the most popular photoelectric detection technologies for military and civilian use in recent years. It is a kind of passive detection. With the continuous development of ultraviolet detector and ultraviolet camera device manufacturing technology, ultraviolet turbidity detection technology will surely become one of the important military equipment technologies.