CN1189922A - 包含浮栅mosfet的光探测器 - Google Patents
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Abstract
光探测器包括能发射光电子的光致发射表面,使用具有浮栅的MOSFET来探测光电子,在测量之前适当给浮栅充电使光电子可引起浮栅电荷的改变,探测到的改变代表由探测器接收到的光量。
Description
最灵敏的光探测器之一是光电倍增管(PMT)或仅仅是光电倍增器。这种装置的基本结构是包含光敏阴极和电子倍增结构的真空管,用高电压对系统加电场,待测光子轰击光电阴极,通过光致发射过程释放光电子。电子倍增器由一系列被称作倍增电极的二次发射电极(一般6-16个)构成,这种排列能够提升电位。从阴极来的光电子射向第一个倍增电极,在这里产生几个二次电子,然后,这些二次电子再射向下一个倍增电极,在这里二次发射再重复发生,依次类推。于是得到了放大,使来自输出电极,阳极的信号足够高,使得在电学上可以处理。光电倍增管的缺点是相对高的成本和需要高电压,这使得它们的通用性受到限制和复杂化。
另一种光探测器是各种半导体光探测器,例如光电二极管,光电三极管,和电荷耦合器件(CCD)。它们的共同点是:光被用来影响半导体材料,在材料中产生电荷载流子(电子和空穴),这些载流子被收集产生电信号。半导体探测器的问题是:载流子必须在半导体材料体中移动,在体内,热能产生高的背景噪声。
本发明公开一种新型光探测器,本探测器价廉,灵敏,且易于构成。它包含一个空腔,此空腔含有能通过响应光电子的光电效应而释放电子(光电子)的光致发射表面。本发明的特征是:光电子由具有浮栅的金属-氧化物-半导体类型的场效应晶体管(MOSFET)探测。测量之前,栅适当地充电。光电子发射引起栅电荷改变,这种改变就代表由探测器接收到光的量。
按照一种实施方式,光电发射表面不附于栅上,测量之前,栅充电到正电位,正电荷吸引光电子且把它们射向栅,在那里正电荷被中和而导致栅电位降低,这种降低就代表由探测器接收到的光量。
按照另一种实施方式,光致发射表面直接地加工在浮栅上,因此,在这种情况下,浮栅在测量之前充上负电。释放的光电子收集到一个分开的阳极电极,或者只是收集到器件外壳的金属壁。这引起栅电位增加,这种增加就代表被光探测器接收到的光的量。
在光电子收集期间,本光探测器不需要任何电功率(电压)。但显然,为了最佳化光电子收集,也可以施加附加电场。
本发明的特征是:从响应光电子光电效应的光致发射表面释放的电子(光电子),允许用来影响MOSFET(金属-氧化物-半导体类型的场效应晶体管)浮栅的表面。本发明是基于测量之前先测量作用到MOSFET浮栅电容中存储的电荷上的光电子效应。
利用浮栅首先被充上合适的电位提供电场效果来收集光电子。例如,用外加FN隧道技术来完成初始充电。
通过测量MOSFET源漏沟道的导电性,不破坏电荷本身就能决定栅的电荷量。这类似于读出存储在模拟EEPROM存储器中所储存的信息。
附图概略示出本发明的实施方式。
附图概略地示出涉及本发明的光探测器的一种实施方式。应当注意,图中的各种部件未按比例示出。光致发射表面20,通过光电效应吸收光电子并释放电子(常称作光电子)。光电发射材料是预先知道的且可以和光电倍增器的光电阴极所用材料相同。
用MOSFET10来探测光电子。MOSFET器件有三个电极,源11,漏12,和栅13。根据本发明,栅13保持不连接,即浮置。例如,通过在源11和漏12之间加足够的高电压,正电荷预先在栅13上形成。这导致通过栅绝缘层14构成的氧化层发生FN隧道现象使浮栅13上的电位设置成所需电荷。
熟知,具有浮栅的MOSFET的电荷保持特性是非常优良的,所以,它们很适合构成不挥发存储器,既包括数字式也包括模拟式EPROM和EEPROM存储器。以前,具有充电浮栅的MOSFET被用作离子辐射探测器,如PCT公开WO 95/12134所示。
正电荷建立吸引光电子的电场,且把光电子射向栅13。在栅13的表面上有一个未覆盖的区域或一个被导体,半导体或薄的绝缘体覆盖的区域。绝缘体的厚度可不超过,例如1mm,仍使电子可通过它达到实际的栅上。然而,最可取的是栅表面的一部分不全覆盖,因此,在浮栅13的氧化物绝缘层14中,已预先形成孔17,光电子可以由此直接地到达栅13的表面。当轰击栅13的时候,光电子在其上中和正电荷而引起栅13的电位降低。所以,在所选时间间隔内,电位的减少量就代表在那个间隔内的由光探测器接收的光的量。
为正确地工作,光致发射表面20和MOSFET 10都被封入封闭的真空管壳21内。管壳21有一个透明部分22,例如玻璃。通过它光子能够达到光发射表面20,图中示出了一个很有用的结构,光致发射表面20被作在透明部分22的内表面上。光致发射表面20连接到壳21的金属壁。显然,光致发射表面也可以适当地深入壳的内腔。
栅13的电位正比于它的电荷,此电位可以用不破坏电荷本身的情况下来测量MOSFET 10的源漏沟道的电导率来决定。例如,利用在源11和漏12之间引入一个合适的电压且测量得到的源-漏电流来测量电导率。换言之,被选定时间间隔内探测的光量,可以用探测间隔之后的源漏电流与栅全充电时的初始值进行比较来决定。
相应地,为了在源11和漏12之间加充电电压来用上面描述的方法测量栅13的电位(电荷)的改变,把源11和漏12利用导体26和27连接到装于壳21壁的接头28和29。
按照发明的另一种实施方式(附图中未表示),光致发射表面直接加工在栅上,在这种情况下,测量之前栅充负电,发射的光电子被收集到分开的阳极或只收集到壳的壁上。这引起栅电位增加,这种增加就代表由探测器接收的光的量。如上述,这是由测量源漏沟道的导电率来决定。
值得指出的是:在光探测(即光电子收集)期间,本光探测器不需要任何电功率(电压),然而,为增强和最佳化光电子收集,自然可以在光致发射表面和浮栅(示于图中)之间,或光致发射表面和阳极之间(图中未示出)提供附加电位。
Claims (10)
1,光探测器包括:
-能响应被探测光子而发射电子的光致发射表面。
-具有浮栅的MOSFET,所述浮栅备有电荷,其配备方式为所述电子发射能引起所述电荷的改变,以及
-包封所述光发射表面和所述MOSFET的外壳,至少所述外壳的一部分透光的,使所述光可以达到所述光致发射表面。
2,根据权利要求1的光探测器,其中所述光致发射表面不与所述浮栅和所述正电荷接触。
3,根据权利要求1的光探测器,其中所述光致发射表面与所述浮栅接触,所述电荷为负。
4,根据权利要求3的光探测器,还包括收集所述电子的装置。
5,光探测器包括:
-能够响应被探测光子而发射电子的光致发射表面。
-具有不与所述光电子发射表面接触的浮栅的MOSFET,所述浮栅备有正电荷,从而所述浮栅能够收集所述电子,以及
-包封所述光致发射表面和所述MOSFET的外壳,至少所述外壳的一部分是透光的,使所述光可以达到所述光致发射表面。
6,根据权利要求5的光探测器,其中所述光致发射表面是加工在所述外壳的所述透明部分的内表面上。
7,光探测器包括:
-能够响应被探测光子而发射电子的光致发射表面,
-具有与所述光致发射表面接触的浮栅的MOSFET,所述浮栅备有负电荷,以及
-包封所述光致发射表面和所述MOSFET的外壳,至少所述外壳的一部分是透光的,以使所述光可以达到所述光致发射表面。
8,根据权利要求5或7的光探测器,还包括寄存所述电荷改变的装置,改变是由所述电子引起的,这种改变因而代表由光探测器吸收的光的量。
9,探测光的方法包括以下步骤:
-提供光探测器,该光探测器包括:能响应被探测光子而发射电子的光致发射表面,具有浮栅的MOSFET,以及包封所述光致发射表面和所述MOSFET的外壳,至少所述外壳的一部分透光的,使所述光能够达到所述光致发射表面。
-把所述浮栅充电到预选电位,
-允许待测光影响所述光致发射表面,从而使电子从光致发射表面发射,引起所述浮栅的所述预选电位的改变,以及
-在选定的时间之后寄存所述预选电位的改变,所述改变代表由所述光探测器接收的光的量。
10,根据权利要求9的探测方法,其中充电步骤是由在所述MOSFET的源电极和漏电极之间外加电压预先形成的。
11,光探测方法包括以下步骤:
-提供光探测器,该光探测器包括:能响应被探测光子而发射电子的光致发射表面,具有浮栅的MOSFET,所述浮栅在其上具有电荷,以及包封所述光致发射表面和所述MOSFET的外壳,至少所述外壳的一部分是透光的,使所述光能达到所述光致发射表面,
-允许待探测光影响所述光致发射表面,从而使电子从光致发射表面发射引起所述电荷的改变,以及
-在选定时间之后寄存所述电荷的改变,所述改变代表由所述光探测器接收来的光量。
Applications Claiming Priority (2)
Application Number | Priority Date | Filing Date | Title |
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FI953240 | 1995-06-30 | ||
FI953240A FI953240A0 (fi) | 1995-06-30 | 1995-06-30 | Ljusdetektor |
Publications (2)
Publication Number | Publication Date |
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CN1189922A true CN1189922A (zh) | 1998-08-05 |
CN1112735C CN1112735C (zh) | 2003-06-25 |
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Application Number | Title | Priority Date | Filing Date |
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CN96195181A Expired - Fee Related CN1112735C (zh) | 1995-06-30 | 1996-06-28 | 包含浮栅mosfet的光探测器 |
Country Status (11)
Country | Link |
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US (1) | US6043508A (zh) |
EP (1) | EP0842545B1 (zh) |
JP (1) | JP3790548B2 (zh) |
CN (1) | CN1112735C (zh) |
AT (1) | ATE274241T1 (zh) |
AU (1) | AU6227196A (zh) |
CA (1) | CA2225226C (zh) |
DE (1) | DE69633183T2 (zh) |
FI (1) | FI953240A0 (zh) |
RU (1) | RU2161348C2 (zh) |
WO (1) | WO1997002609A1 (zh) |
Cited By (4)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101303239B (zh) * | 2007-05-10 | 2010-05-26 | 北方工业大学 | 一种传感器及其调节方法 |
CN101807547B (zh) * | 2009-02-18 | 2013-07-10 | 南京大学 | 光敏复合介质栅mosfet探测器 |
CN104900745A (zh) * | 2015-05-26 | 2015-09-09 | 北京工业大学 | 一种基于高电子迁移率晶体管的光谱探测器及其制备方法 |
CN110767519A (zh) * | 2019-10-21 | 2020-02-07 | 中国电子科技集团公司第十二研究所 | 一种场发射电子源结构及其形成方法、电子源、微波管 |
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JP2000088645A (ja) | 1998-09-16 | 2000-03-31 | Hamamatsu Photonics Kk | 積分型光検出装置 |
US7166830B2 (en) * | 2002-04-17 | 2007-01-23 | Hamamatsu Photonics K.K. | Light detecting sensor |
KR100499956B1 (ko) * | 2002-10-24 | 2005-07-05 | 전자부품연구원 | 양자채널이 형성된 모스펫을 이용한 포토디텍터 및 그제조방법 |
FR2911191B1 (fr) * | 2007-01-09 | 2009-07-10 | Microcomposants De Haute Secur | Capteur de mesure d'une dose d'uv et procede de mesure d'une dose d'uv mettant en oeuvre ce capteur |
US8068190B2 (en) * | 2008-09-02 | 2011-11-29 | Sharp Kabushiki Kaisha | Display device |
US9219177B2 (en) | 2010-04-07 | 2015-12-22 | International Business Machines Corporation | Photo detector and integrated circuit |
WO2013024386A2 (en) * | 2011-08-16 | 2013-02-21 | 0Ec Sa | System for a contactless control of a field effect transistor |
US8653618B2 (en) * | 2011-09-02 | 2014-02-18 | Hoon Kim | Unit pixel of color image sensor and photo detector thereof |
US9213112B2 (en) | 2013-03-15 | 2015-12-15 | Starfire Industries, Llc | Neutron radiation sensor |
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EP0002420A1 (fr) * | 1977-12-01 | 1979-06-13 | International Business Machines Corporation | Dispositif semi-conducteur du type transistor à effet de champ activé par la lumière et mémoire en résultant |
DE3413829A1 (de) * | 1984-04-10 | 1985-10-17 | Hahn-Meitner-Institut für Kernforschung Berlin GmbH, 1000 Berlin | Mos-dosimeter |
US5471051A (en) * | 1993-06-02 | 1995-11-28 | Hamamatsu Photonics K.K. | Photocathode capable of detecting position of incident light in one or two dimensions, phototube, and photodetecting apparatus containing same |
FI934784A0 (fi) * | 1993-10-28 | 1993-10-28 | Rados Technology Oy | Straolningsdetektor |
US5804833A (en) * | 1996-10-10 | 1998-09-08 | Advanced Scientific Concepts, Inc. | Advanced semiconductor emitter technology photocathodes |
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1995
- 1995-06-30 FI FI953240A patent/FI953240A0/fi not_active Application Discontinuation
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1996
- 1996-06-28 EP EP96920861A patent/EP0842545B1/en not_active Expired - Lifetime
- 1996-06-28 CA CA002225226A patent/CA2225226C/en not_active Expired - Fee Related
- 1996-06-28 DE DE69633183T patent/DE69633183T2/de not_active Expired - Lifetime
- 1996-06-28 WO PCT/FI1996/000380 patent/WO1997002609A1/en active IP Right Grant
- 1996-06-28 US US08/981,724 patent/US6043508A/en not_active Expired - Lifetime
- 1996-06-28 JP JP50485197A patent/JP3790548B2/ja not_active Expired - Fee Related
- 1996-06-28 RU RU98101464/28A patent/RU2161348C2/ru not_active IP Right Cessation
- 1996-06-28 CN CN96195181A patent/CN1112735C/zh not_active Expired - Fee Related
- 1996-06-28 AU AU62271/96A patent/AU6227196A/en not_active Abandoned
- 1996-06-28 AT AT96920861T patent/ATE274241T1/de not_active IP Right Cessation
Cited By (5)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN101303239B (zh) * | 2007-05-10 | 2010-05-26 | 北方工业大学 | 一种传感器及其调节方法 |
CN101807547B (zh) * | 2009-02-18 | 2013-07-10 | 南京大学 | 光敏复合介质栅mosfet探测器 |
CN104900745A (zh) * | 2015-05-26 | 2015-09-09 | 北京工业大学 | 一种基于高电子迁移率晶体管的光谱探测器及其制备方法 |
CN110767519A (zh) * | 2019-10-21 | 2020-02-07 | 中国电子科技集团公司第十二研究所 | 一种场发射电子源结构及其形成方法、电子源、微波管 |
CN110767519B (zh) * | 2019-10-21 | 2022-03-04 | 中国电子科技集团公司第十二研究所 | 一种场发射电子源结构及其形成方法、电子源、微波管 |
Also Published As
Publication number | Publication date |
---|---|
JPH11509366A (ja) | 1999-08-17 |
EP0842545B1 (en) | 2004-08-18 |
EP0842545A1 (en) | 1998-05-20 |
WO1997002609A1 (en) | 1997-01-23 |
AU6227196A (en) | 1997-02-05 |
US6043508A (en) | 2000-03-28 |
RU2161348C2 (ru) | 2000-12-27 |
CA2225226C (en) | 2003-01-21 |
JP3790548B2 (ja) | 2006-06-28 |
DE69633183T2 (de) | 2005-08-18 |
FI953240A0 (fi) | 1995-06-30 |
ATE274241T1 (de) | 2004-09-15 |
CA2225226A1 (en) | 1997-01-23 |
DE69633183D1 (de) | 2004-09-23 |
CN1112735C (zh) | 2003-06-25 |
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