JPS63177574A - Semiconductor radiation detector - Google Patents
Semiconductor radiation detectorInfo
- Publication number
- JPS63177574A JPS63177574A JP62009248A JP924887A JPS63177574A JP S63177574 A JPS63177574 A JP S63177574A JP 62009248 A JP62009248 A JP 62009248A JP 924887 A JP924887 A JP 924887A JP S63177574 A JPS63177574 A JP S63177574A
- Authority
- JP
- Japan
- Prior art keywords
- main
- oxide film
- electrode
- main surface
- main electrode
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Pending
Links
- 230000005855 radiation Effects 0.000 title claims description 26
- 239000004065 semiconductor Substances 0.000 title claims description 17
- 239000000758 substrate Substances 0.000 claims abstract description 20
- 238000001514 detection method Methods 0.000 claims description 19
- 239000013078 crystal Substances 0.000 claims description 3
- 239000012535 impurity Substances 0.000 claims description 3
- 229910021421 monocrystalline silicon Inorganic materials 0.000 abstract description 10
- 230000004888 barrier function Effects 0.000 abstract description 6
- 229910052751 metal Inorganic materials 0.000 abstract description 5
- 239000002184 metal Substances 0.000 abstract description 5
- 238000006073 displacement reaction Methods 0.000 abstract description 3
- 238000000034 method Methods 0.000 abstract 1
- 229910021417 amorphous silicon Inorganic materials 0.000 description 6
- 239000000969 carrier Substances 0.000 description 5
- 238000010586 diagram Methods 0.000 description 5
- 238000009825 accumulation Methods 0.000 description 2
- 230000003993 interaction Effects 0.000 description 2
- 230000035945 sensitivity Effects 0.000 description 2
- 238000001228 spectrum Methods 0.000 description 2
- 230000001360 synchronised effect Effects 0.000 description 2
- UFHFLCQGNIYNRP-UHFFFAOYSA-N Hydrogen Chemical compound [H][H] UFHFLCQGNIYNRP-UHFFFAOYSA-N 0.000 description 1
- 229910052782 aluminium Inorganic materials 0.000 description 1
- XAGFODPZIPBFFR-UHFFFAOYSA-N aluminium Chemical compound [Al] XAGFODPZIPBFFR-UHFFFAOYSA-N 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- 239000002019 doping agent Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 229910052739 hydrogen Inorganic materials 0.000 description 1
- 239000001257 hydrogen Substances 0.000 description 1
- 230000000737 periodic effect Effects 0.000 description 1
Classifications
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
- Y02E10/00—Energy generation through renewable energy sources
- Y02E10/50—Photovoltaic [PV] energy
Abstract
Description
【発明の詳細な説明】
〔産業上の利用分野〕
本発明は半導体内に形成された空乏層中へ入射する放射
線によって生ずるキャリアを利用した半導体放射線検出
素子に関するＯ
〔従来の技術〕
上記半導体放射線検出素子に関して単結晶シリコン基板
の少なくとも一主面に高比抵抗の非晶質シリコン層を介
して電極を形成したものを本発明者らは特開昭５９−２
２７１６８号公報により開示している。Detailed Description of the Invention [Industrial Application Field] The present invention relates to a semiconductor radiation detection element that utilizes carriers generated by radiation incident on a depletion layer formed in a semiconductor. The present inventors have developed a detection element in which an electrode is formed on at least one main surface of a single crystal silicon substrate via an amorphous silicon layer with high resistivity, as described in Japanese Patent Laid-Open No. 59-2.
It is disclosed in Japanese Patent No. 27168.
この半導体放射線検出素子の構造を第６図の断面図に示
す０第６図において、この素子は単結晶シリコン基板１
の一主面に、水素を添加しドーパントを含まない高比抵
抗非晶質シリコン層２を成長させ、その上に主電極３と
基板１のもう一方の主面に裏面電極４を設けてあシ、基
板１と主電極３との間に高比抵抗の非晶質シリコン層２
を介在させるととくよ）主電極３と裏面電極４の間に逆
バイアス電圧を印加して、基板１と非晶質シリコン層２
のヘテ四接合部に大きなエネルギー障壁を形成させ、点
線で示した空乏層５を拡げ、この空乏層５の中に入射し
てくる放射線と基板１の結晶格子との相互作用による電
子正孔対を捕獲し放射線を検出するものである０
〔発明が解決しようとする問題点〕
ところで第６図に示すようま非晶質シリコンと単結晶シ
リコンとのへテロ接合型またはＰＮ接合型などの半導体
放射線検出素子における最大の問照点は逆漏れ電流であ
る。接合型のダイオード構造では、接合部の形成の仕方
によっては結晶欠陥の少ない良質な接合部が得られず逆
漏れ電流が大きくなシノイズも増すようになる。逆漏れ
電流が大きくなると素子に接続する負荷での電圧降下も
大きくなシ、空乏層を十分に拡げることができず、放射
線検出の感度の低下を招く。また空乏層の拡がシが小さ
いと静電容量が増加して回路上からもノイズが増す〇
本発明は上述の点に鑑みてなされたものであシ、その目
的は従来とは異なる構造をもつ逆漏れ電流の小さい半導
体放射線検出素子を提供することにある。The structure of this semiconductor radiation detection element is shown in the cross-sectional view of FIG.
A high resistivity amorphous silicon layer 2 doped with hydrogen and containing no dopants is grown on one main surface, and a main electrode 3 and a back electrode 4 are provided on the other main surface of the substrate 1. A high resistivity amorphous silicon layer 2 between the substrate 1 and the main electrode 3
By applying a reverse bias voltage between the main electrode 3 and the back electrode 4, the substrate 1 and the amorphous silicon layer 2 are
A large energy barrier is formed at the heterojunction of the substrate 1 to expand the depletion layer 5 shown by the dotted line, and electron-hole pairs are created by the interaction between the radiation entering the depletion layer 5 and the crystal lattice of the substrate 1. [Problem to be solved by the invention] By the way, as shown in Fig. 6, a semiconductor such as a heterojunction type or PN junction type of amorphous silicon and single crystal silicon The most important point of inquiry in radiation detection elements is reverse leakage current. In a junction diode structure, depending on how the junction is formed, a high-quality junction with few crystal defects may not be obtained, resulting in increased reverse leakage current and noise. When the reverse leakage current increases, the voltage drop across the load connected to the element also increases, and the depletion layer cannot be sufficiently expanded, resulting in a decrease in radiation detection sensitivity. Furthermore, if the expansion of the depletion layer is small, the capacitance increases and the noise from the circuit increases.The present invention was made in view of the above points, and its purpose is to create a structure different from the conventional one. An object of the present invention is to provide a semiconductor radiation detection element having a small reverse leakage current.
本発明の半導体放射検出素子は第１図にその構造を断面
図で示したように、単結晶シリコン基板１のいずれか一
方の主面に形成した酸化膜６上に主電極３を設け、基板
１の主電極３とは反対側の主面に裏面電極４を形成しＭ
ＩＳ構造としたものである。As shown in FIG. 1 in cross-sectional view, the semiconductor radiation detection element of the present invention has a main electrode 3 on an oxide film 6 formed on one of the main surfaces of a single-crystal silicon substrate 1. A back electrode 4 is formed on the main surface opposite to the main electrode 3 of M
It has an IS structure.
本発明の半導体放射線素子は基板１と主電極３の間に介
在している酸化膜６のエネルギー障壁が極めて高いので
トンネル電流や変位電流のほかにはほとんど逆漏れ電流
は流れず、放射線の入射によって発生するキャリアの蓄
積に対してはとれらを除くために交流電圧を印加して逆
方向電圧が印加される空乏層形成時のみ同期するシグナ
ルを引き出すようＫする。In the semiconductor radiation device of the present invention, since the energy barrier of the oxide film 6 interposed between the substrate 1 and the main electrode 3 is extremely high, almost no reverse leakage current flows other than the tunnel current and displacement current, and the incident radiation In order to eliminate the accumulation of carriers caused by the above, an alternating current voltage is applied to extract a synchronized signal only when a reverse voltage is applied to form a depletion layer.
以下本発明を実施例に基づき説明する。 The present invention will be explained below based on examples.
第１図は本発明の半導体放射線検出素子の構造断面図で
あシ、第６図と共通部分を同一符号で示しである◎第１
図において本発明の素子は単結晶シリコン基板１の一主
面に酸化膜６が介在するようにして主電極３を設け、基
板１の主電極３とは反対側の面に裏面電極４を形成した
ＭＩＳ構造をもっておシ、例えば基板ＩＫ比抵抗１０
ｋＱａｎのＰ型単結晶シリコンを用い、酸化膜６は１０
００〜２０００Ａ０の熱酸化膜１両電極３，４は金属ア
ルミニウムからなる。また裏面電極４と単結晶シリ；ン
基板１との間にオーミンクな接触を形成するため、高濃
度不純物層７を介在させるのもよい◇そして主電極３に
正の電圧を印加し、裏面電極４に負の電圧を印加するこ
とによシ印加電圧に応じて空乏層５を形成することがで
きる。Fig. 1 is a cross-sectional view of the structure of the semiconductor radiation detection element of the present invention, and parts common to Fig. 6 are indicated by the same symbols.
In the figure, in the device of the present invention, a main electrode 3 is provided on one main surface of a single crystal silicon substrate 1 with an oxide film 6 interposed therebetween, and a back electrode 4 is formed on the surface of the substrate 1 opposite to the main electrode 3. For example, if you have a MIS structure with a substrate IK resistivity of 10
P-type single crystal silicon of kQan is used, and the oxide film 6 has a thickness of 10
00-2000A0 Thermal oxide film 1 Both electrodes 3 and 4 are made of metal aluminum. In addition, in order to form an ohmink contact between the back electrode 4 and the single crystal silicon substrate 1, it is good to interpose a high concentration impurity layer 7◇Then, a positive voltage is applied to the main electrode 3, and the back electrode By applying a negative voltage to 4, a depletion layer 5 can be formed depending on the applied voltage.
第２図に本発明の素子のエネルギーバンド構造を示した
。第２図に見られるように、金属側に正の電圧を印加す
ると、この印加電圧の大きさに依存してバンドは曲げら
れる０実際の漏れ電流はＰ形半導体の伝導帯Ｅｃの上と
価電子帯ｇｖの下にそれぞれ存在す電子と正孔のいずれ
かが酸化膜を介して金属側に通過したときに生ずる。し
かし第２図 。FIG. 2 shows the energy band structure of the device of the present invention. As seen in Figure 2, when a positive voltage is applied to the metal side, the band bends depending on the magnitude of the applied voltage.The actual leakage current is above the conduction band Ec of the P-type semiconductor. This occurs when either electrons or holes, which exist below the electron band gv, pass through the oxide film to the metal side. However, Fig. 2.
のように仲介する酸化膜のエネルギー障壁が極めて高い
ので、ＰＮ接合による障壁に比べると電子および正孔は
ほとんど通過することができない。したがってトンネル
電流や変位電流のほかにはほとんど漏れ電流は流れない
。Since the energy barrier of the intervening oxide film is extremely high, compared to the barrier caused by the PN junction, electrons and holes can hardly pass through. Therefore, other than tunnel current and displacement current, almost no leakage current flows.
また、印加電圧の低いうちは徐々に空乏層が拡が９はじ
めるがある程度印加電圧が大きくなると、強い電圧にひ
かれて電子が酸化膜直下に引き寄せられ反転層が生じ空
乏層が縮小し、空乏層に入射した放射線との相互作用に
よって発生したキャリアも蓄積されてしまう。とのため
チャージアップ現象を生じゃすくなシ、蓄積されたキャ
リアを開放してしまわなければならない。In addition, when the applied voltage is low, the depletion layer gradually begins to expand9, but when the applied voltage increases to a certain extent, electrons are drawn directly under the oxide film due to the strong voltage, forming an inversion layer, and the depletion layer shrinks. Carriers generated by interaction with the radiation incident on the surface also accumulate. Therefore, in order to avoid the charge-up phenomenon, the accumulated carrier must be released.
そこで例えば第３図■に示す波形の交流パルス電圧を印
加すれば＋側電圧のときにのみ空乏層が形成され一側の
ときすなわち逆方向電圧では空乏層が形成されずキャリ
アは開放される。このように交流電圧を印加することに
よ）周期的な逆方向電圧によって蓄積された電子をと勺
除く必要がある。したがって空乏層の形成時のみ放射線
検出のシグナルを引き出すように第３図■のような信号
をこれに同期させればよい。For example, if an AC pulse voltage having the waveform shown in FIG. 3 is applied, a depletion layer is formed only when the voltage is on the positive side, and when the voltage is on the one side, that is, in the reverse direction, no depletion layer is formed and carriers are released. By applying an alternating current voltage in this way, it is necessary to remove the accumulated electrons due to the periodic reverse voltage. Therefore, it is only necessary to synchronize a signal as shown in FIG. 3 (2) so that the radiation detection signal is extracted only when the depletion layer is formed.
第４図は本発明の半導体放射線検出素子を用いて構成し
た検出回路の要部を示したものである。FIG. 4 shows the main parts of a detection circuit constructed using the semiconductor radiation detection element of the present invention.
第４図の交流電源８は第３図■に相当する波形のパルス
電圧を検出素子９に印加し、波形選択回路１０は第３図
■に相当し、素子の空乏層形成時のみこれと同期させる
信号発生装置であシ、放射線を検出するシグナルはプリ
アンプ１１．メインアンプ１２によって増幅され電子−
正孔対がカウントされる。The AC power source 8 in FIG. 4 applies a pulse voltage with a waveform corresponding to the waveform shown in FIG. The signal for detecting radiation is generated by a preamplifier 11. The main amplifier 12 amplifies the electronic
Hole pairs are counted.
第５図は本発明の素子に２４１Ａｍを用いた放射線スペ
クトル線図を従来のＰＮ接合型検出素子との比較で表わ
したものである◇第５図中実線曲線イが本発明１口が従
来素子の場合であシ、第５図から本発明の素子の方が２
４１Ａｍのエネルギーを表わす５９、５ ｅＶのピーク
２点が明瞭に表われていることがわかる。Fig. 5 shows a radiation spectrum diagram using 241Am as the element of the present invention in comparison with a conventional PN junction type detection element. In the case of
It can be seen that two peaks at 59.5 eV representing the energy of 41 Am are clearly visible.
従来の半導体放射線検出素子の最大の問題であった逆漏
れ電流に対して、本発明では基板と主電極との間に酸化
膜を介在させたＭＩＳ構造としたために、酸化膜の高い
エネルギー障壁のためにほとんど逆漏れ電流が流れず、
印加電圧によるキャリアの蓄積に対しては交流電圧を印
加して空乏層形成時のみ放射線のシグナルをと）出すよ
うにして検出感度をあげ、ノイズの増加を抑え、低エネ
ルギーの放射線も十分に検出することができたものであ
る。To address reverse leakage current, which was the biggest problem with conventional semiconductor radiation detection elements, the present invention employs an MIS structure in which an oxide film is interposed between the substrate and the main electrode. Therefore, almost no reverse leakage current flows,
To deal with the accumulation of carriers due to applied voltage, an AC voltage is applied to emit a radiation signal only when a depletion layer is formed, increasing detection sensitivity, suppressing noise increase, and sufficiently detecting low-energy radiation. It was possible to do so.
第１図は本発明の半導体放射線検出素子の要部構成断面
図、第２図は本発明素子のエネルギーバンド構造図、第
３図は本発明素子に印加する交流電圧波形および放射線
シグナルをと）だすための同期パルス信号波形図、第４
図は本発明の素子を用いた放射線検出回路図、第５図は
本発明の素子によシ得られる放射線スペクトル線図、第
６図は従来素子の要部構成断面図である。
１・・・・・・単結晶シリコン基板、２・・・・・・非
晶質シリコン層、３・−・・・・主電極、４・・・・・
・裏面電極、５・・・・・・空乏層、６・・・・・・酸
化膜、７・・・・・・高濃度不純物層。
８・・・・・・交流電源、９・−・・・・検出素子、１
０・・・・・・波形選択回路、１１・・・・・・プリア
ンプ、１２・・・・−・メインアンプ。
第１区
第３図
第４図
チャ、！７一ンレFig. 1 is a cross-sectional view of the main parts of the semiconductor radiation detection device of the present invention, Fig. 2 is an energy band structure diagram of the device of the present invention, and Fig. 3 shows the AC voltage waveform and radiation signal applied to the device of the present invention. Synchronous pulse signal waveform diagram for output, 4th
5 is a radiation detection circuit diagram using the device of the present invention, FIG. 5 is a radiation spectrum diagram obtained by the device of the present invention, and FIG. 6 is a sectional view of the main part of the conventional device. 1... Single crystal silicon substrate, 2... Amorphous silicon layer, 3... Main electrode, 4...
- Back electrode, 5... depletion layer, 6... oxide film, 7... high concentration impurity layer. 8...AC power supply, 9...detection element, 1
0... Waveform selection circuit, 11... Preamplifier, 12... Main amplifier. District 1, Figure 3, Figure 4 Cha! 71 inre
Claims (1)
して設けた主電極と前記基板の前記主電極とは反対の面
に設けた裏面電極とを備えたことを特徴とする半導体放
射線検出素子。 ２）特許請求の範囲第１項記載の検出素子において、裏
面電極との接触面に一導電形半導体の高濃度不純物層を
有する基板を用いることを特徴とする半導体放射線検出
素子。[Claims] 1) A main electrode provided on one main surface of a single crystal semiconductor substrate of one conductivity type via an oxide film, and a back electrode provided on a surface of the substrate opposite to the main electrode. A semiconductor radiation detection element characterized by: 2) A semiconductor radiation detection element according to claim 1, characterized in that a substrate having a high concentration impurity layer of one conductivity type semiconductor is used on the contact surface with the back electrode.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62009248A JPS63177574A (en) | 1987-01-19 | 1987-01-19 | Semiconductor radiation detector |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| JP62009248A JPS63177574A (en) | 1987-01-19 | 1987-01-19 | Semiconductor radiation detector |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| JPS63177574A true JPS63177574A (en) | 1988-07-21 |
Family
ID=11715105
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| JP62009248A Pending JPS63177574A (en) | 1987-01-19 | 1987-01-19 | Semiconductor radiation detector |
Country Status (1)
| Country | Link |
|---|---|
| JP (1) | JPS63177574A (en) |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2013503481A (en) * | 2009-08-31 | 2013-01-31 | ゼネラル・エレクトリック・カンパニイ | Radiation detector with semiconductor crystal and method for manufacturing the detector |
-
1987
- 1987-01-19 JP JP62009248A patent/JPS63177574A/en active Pending
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2013503481A (en) * | 2009-08-31 | 2013-01-31 | ゼネラル・エレクトリック・カンパニイ | Radiation detector with semiconductor crystal and method for manufacturing the detector |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Liao et al. | Single Schottky-barrier photodiode with interdigitated-finger geometry: Application to diamond | |
| Liang et al. | Electrical properties of Si/Si interfaces by using surface-activated bonding | |
| Alberi et al. | Material quality requirements for efficient epitaxial film silicon solar cells | |
| US11119228B2 (en) | Radiation detector and radiation detection device using the same | |
| DE2160033A1 (en) | Radiation-sensitive semiconductor device | |
| JPS63177574A (en) | Semiconductor radiation detector | |
| JPS59500539A (en) | photodetector | |
| US4524374A (en) | Device for detecting infrared rays | |
| JPH02111080A (en) | Amorphous thin-film solar cell | |
| US3466448A (en) | Double injection photodetector having n+-p-p+ | |
| CN111668327B (en) | Capacitive photoelectric detector | |
| JP2505284B2 (en) | Semiconductor position detector | |
| JP3295725B2 (en) | Photoelectric conversion element | |
| JP3036258B2 (en) | Semiconductor radiation detector | |
| JPS63314422A (en) | Infrared sensor | |
| JPH06283750A (en) | Junction type semiconductor element | |
| Song et al. | Application of poly-Si/SiOx passivating contact in x-ray silicon pixel detector | |
| JPH05226686A (en) | Photodetector | |
| JPS61268072A (en) | Thin-film photoelectric conversion element | |
| Fernandes et al. | Photocurrent multiplication in ITO/SiOx/Si optical sensors | |
| JPH0529647A (en) | Photodetector | |
| JPS62293681A (en) | Semiconductor radiation detecting element | |
| JPS62272573A (en) | Photoconductive thin film element | |
| JPH08242014A (en) | Semiconductor radiation detecting element | |
| JPS6242467A (en) | Photoelectric conversion element |