CN1328598C - Method for preparing coplanar grid anode tellurium-zinc-cadmium detector - Google Patents
Method for preparing coplanar grid anode tellurium-zinc-cadmium detector Download PDFInfo
- Publication number
- CN1328598C CN1328598C CNB200510023578XA CN200510023578A CN1328598C CN 1328598 C CN1328598 C CN 1328598C CN B200510023578X A CNB200510023578X A CN B200510023578XA CN 200510023578 A CN200510023578 A CN 200510023578A CN 1328598 C CN1328598 C CN 1328598C
- Authority
- CN
- China
- Prior art keywords
- electrode
- cadmium
- tellurium
- crystal
- wafer
- 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.)
- Expired - Fee Related
Links
Abstract
The present invention relates to a method for preparing coplanar grid anode tellurium-zinc-cadmium detectors, which belongs to the technical field of manufacturing technique of semiconductor crystal nuclear detectors. The detector is composed of a tellurium-zinc-cadmium crystal, the positive electrodes of the crystal and the negative electrode of the crystal. The preparation method of the detector has the following procedures that surface treatment of coarse polishing, fine polishing, surface chemistry corrosion and cleaning is carried out on a well cut tellurium-zinc-cadmium wafer with a definite size and an oriented crystal face direction (111), and then the electrodes are made; vacuum evaporation is used for precipitating the electrodes during the preparation of the electrodes, and two groups of micro bar-shaped interdigital positive electrodes are obtained by using photolithography technology; the negative electrode is a complete plane electrode, and the two groups of positive electrodes and the cathode electrode are all led out by filigree leading wires; the precipitated electrodes are chromium alloy composite electrodes, passivation is carried out on the surfaces of wafers which are not precipitated with electrode coatings finally, and the coplanar grid anode tellurium-zinc-cadmium detector is manufactured at last. The detector manufactured by using the method of the present invention has better energy resolution for rays.
Description
Technical field
The present invention relates to a kind of preparation method of coplanar grid anode tellurium-zinc-cadmium detector, belong to semiconductor crystal nuclear detector manufacturing process technology field.
Background technology
Semiconductor detector is a kind of novel nuclear radiation detection element that has obtained developing rapidly since the sixties in 20th century, and its feature is: the energy resolution height, and linear response is good, and pulse rise time is short, and is simple in structure, the detection efficiency height, operating voltage is low, and is easy to operate.After U.S. Bel's telecommunication telephone laboratory in 1949 utilized germanium (Ge) semiconductor particle detection first, this detector caused attracting attention of countries in the world at once.Rise the seventies, along with the preparation technology of silicon (Si) material and updating of semiconductor planar technology, makes the Si detector obtain very fast development, particularly obtained using widely in the Detection Techniques of particle physics.But in strong radiation environment, the Si lattice is vulnerable to radiation damage, and the leakage current of detector is increased, and performance descends.The intrinsic conductivity that is produced by thermal excitation increases by index with temperature in addition, and therefore the cooling system that need be assisted when working by the device of silicon materials manufacturing has increased cost, has limited the application of silicon detector aspect portable device.
The counterfeit Binary compound semiconductor detecting material of tellurium zinc cadmium (CZT) is owing to have higher average atomic number and bigger energy gap, so the detector of being made by these materials has bigger absorption coefficient, and higher counting rate, very high detection efficiency.This novel ray detector of CZT is compared with the Si detector, and it can remove cooling system from working and room temperature, so the detection system volume is little, and is easy to use.It is compared with traditional sodium iodide scintillator probe, has higher energy resolution.And, the CZT detector is easy to be processed into picture element array structure, the integrated signal read circuit of silicon that cooperates bridge joint, can make compactness, efficient, high-resolution x and gamma imaging device, can be widely used in aspects such as the detection of airport and port security, nuke rubbish monitoring, industrial flaw detection, medical diagnosis, celestial body x-ray telescope, therefore become the current focus of research in the world.
But owing at present about mobility-life-span product (μ τ) the low order of magnitude of the mobility-life-span product (μ τ) in the hole of the getable CZT material of institute, make that hole collection characteristic is relatively poor relatively than electronics.The negative electrode and the anode of traditional metal-semiconductor-metal (MSM) detector all adopt plane electrode, the electronics that is produced by actinism during device work is to the higher anode movement of electromotive force, the hole is to the lower cathode motion of electromotive force, and the induced charge that obtains at last comes from the two-part contribution of electronics and hole.But because the collection efficiency in hole is lower, near the hole of being excited to produce the anode is difficult to be collected by negative electrode, produces so-called hole low energy " tail ", and this just causes descending by spectral resolution of device, when serious spectral line can not be differentiated.In addition, the transport property missionary society in hole reduces the efficient of device, has only the hole that produces in the physical size of close negative electrode a few percent just spectrum peak counting to be had contribution in the device.Therefore the collection efficiency in hole has limited the widespread use, the particularly application aspect the large volume device of metal-semiconductor-metal (MSM) structure.
Summary of the invention
The object of the present invention is to provide a kind of tellurium-zinc-cadmium detector and manufacture method thereof with coplanar grid anode structure.Another object of the present invention is to overcome the low defective of CZT material hole collection efficiency, and the acquisition electrode pattern is complete, the high coplanar grid anode of contact adhesion, makes electrode and tellurium-zincium-cadmium crystal form Ohmic contact, finally improves the combination property of CZT detector.
For achieving the above object, the present invention adopts following technical scheme:
The preparation method of coplanar grid anode tellurium-zinc-cadmium detector of the present invention, this detector is made up of tellurium-zincium-cadmium crystal and anode thereof and negative electrode, it is characterized in that the preparation method of this detector has following steps::
A. the surface treatment of tellurium-zincium-cadmium crystal: at first the cadmium zinc telluride crystal wafer of well cutting is slightly thrown with emery, clean subsequently, and put into the beaker sonic oscillation 5 minutes that fills deionized water, surface contamination that produces when removing thick throw and the foreign particle that is adsorbed on wafer surface, with the corundum powder polishing fluid cadmium zinc telluride crystal wafer is carefully thrown then, be minute surface until wafer surface; Remove surface impurity with sonic oscillation more subsequently, the cadmium zinc telluride crystal wafer after will polishing then is immersed in and carries out the surface chemistry corrosion in the BM corrosive liquid, and the time is 1-2 minute, and the BM corrosive liquid is the mixed solution of volume ratio 5%Br and absolute methanol; To re-use LB corrosive liquid (volume ratio 2%Br+20% lactic acid+ethylene glycol) after the rinse in methyl alcohol through the wafer after the corrosion of BM corrosive liquid corrodes wafer, to increase the wafer surface smooth degree, the LB corrosive liquid is 2%Br, 20% lactic acid and ethylene glycol mixtures; The ultrasonic cleaning three times in methyl alcohol of the wafer of finishing corrosion, each time is 5-10 minute, to remove surperficial remaining Br and other impurity;
B. the preparation of electrode: will corrode good cadmium zinc telluride crystal wafer and take out, at N
2Dry up under the protective atmosphere, prepare preparation negative electrode and anode; Vacuum evaporation or electron beam evaporation method deposition chromium billon combination electrode are adopted in the preparation of negative electrode, and what be close to the tellurium-zincium-cadmium crystal lower surface is chromium electrode, is gold electrode on it; Negative electrode is made plane-shaped electrode, has gold or platinum to draw on this electrode; The preparation of anode is by MJB6 type litho machine, evenly apply one deck photoresist virgin rubber at the cadmium zinc telluride crystal wafer top surface, through behind the ultraviolet exposure, develop with 4-methyl-aqua ammonia aqueous solution and to obtain the electrode pattern of two groups of required interdigital, use vacuum evaporation afterwards, perhaps electron beam evaporation method deposits chromium billon combination electrode, the photoresist that adopts anhydrous propanone will remain in wafer surface is then peeled off together with the chromium billon that is deposited on this part photoresist, finally support the anode of little strip electrode pattern of two groups of coplanar interdigitals at the wafer top surface, the chromium electrode that is of being close to the tellurium-zincium-cadmium crystal surface, be gold electrode on it, every group of little strip electrode has spun gold or platinum line to draw;
C. surface passivation:, need carry out passivation to the plane of crystal that does not have depositing electrode in order to reduce the tracking current of device; The tellurium zinc chrome crystal that will prepare electrode earlier carries out surface treatment with KOH-KCl solution, then uses the NH of 10wt% again
4F/H
2O
2Mixed solution carries out passivation, and the Passivation Treatment time is 10-30 minute; The tellurium-zincium-cadmium crystal sample is put into a large amount of deionized waters fully to be cleaned to remove the various ions of remained on surface; Finally make coplanar grid anode tellurium-zinc-cadmium detector.
In the inventive method, tellurium-zincium-cadmium crystal is to be of a size of 10 * 10 * 10mm through cutting
3-10 * 10 * 15mm
3Distance side's body wafer, and its crystal plane direction belongs to (111) crystal face type.
Compare with prior art, the present invention has following remarkable advantage: the tellurium-zinc-cadmium detector of the coplanar grid anode structure that the present invention makes, because its anode is constituted by little strip electrode of two groups of copline interdigitals, and be composited by the chromium billon by deposition process, this electrode pattern is complete, contact adhesion height, make electrode and cadmium zinc telluride crystal wafer form Ohmic contact, thereby overcome the low defective of tellurium zinc cadmium material hole collection efficiency, finally improved the combination property of detector.
Description of drawings
Fig. 1 is the basic structure synoptic diagram of coplanar grid anode tellurium-zinc-cadmium detector device of the present invention
Fig. 2 is the vertical view of coplanar grid anode of the present invention
Embodiment
Embodiment one: the preparation method of present embodiment coplanar grid anode tellurium-zinc-cadmium detector is as follows:
A. the surface treatment of tellurium-zincium-cadmium crystal: well cutting is of a size of 10 * 10 * 10mm
3, crystal plane direction is slightly thrown with emery for the cube wafer of (111) type, and the tangible concavo-convex damage of CZT wafer surface is polished, and makes every effort to surfacing, no marking and wire drawing.Clean subsequently, and put into the beaker sonic oscillation 5 minutes that fills deionized water, surface contamination that produces when removing thick throw and the foreign particle that is adsorbed on wafer surface, on muller, be that the corundum powder polishing fluid of 1um, 0.5um, 0.2um is carefully thrown the CZT wafer with particle diameter successively then, be minute surface until wafer surface.Remove surface impurity with sonic oscillation once more, wafer is immersed in waits in the absolute methanol to corrode.CZT wafer after the polishing adopts BM corrosive liquid (mixed liquor of volume ratio 5%Br and absolute methanol) to carry out the surface chemistry corrosion earlier, and the time is 2 minutes; To in methyl alcohol, re-use LB corrosive liquid (volume ratio 2%Br, 20% lactic acid and ethylene glycol mixtures) after the rinse through the wafer after the corrosion of BM corrosive liquid the CZT wafer will be corroded, to increase the wafer surface smooth degree.The ultrasonic cleaning three times in methyl alcohol of the wafer of finishing corrosion, each time is 5 minutes, to remove surperficial remaining Br and other impurity;
B. the preparation of electrode: will corrode good CZT wafer and take out, at N
2Dry up under the protective atmosphere, prepare preparation anode and negative electrode; Vacuum evaporation or electron-beam evaporation chromium gold combination electrode are adopted in the preparation of negative electrode, are close to the chromium electrode that is of cadmium zinc telluride crystal wafer lower surface, and thickness is 50nm, it above it gold electrode, thickness is 500nm, and negative electrode is made plane-shaped electrode, and this electrode has gold wire to draw.The preparation of anode applies the photoresist virgin rubber that a layer thickness is 1-5 μ m (positive glue) by MJB6 type litho machine equably in wafer surface.Through behind the ultraviolet exposure, adopting percent by volume is that 4-methyl-aqua ammonia aqueous solution of 10% is developed and obtained required electrode pattern, afterwards with vacuum evaporation or electron-beam evaporation chromium gold combination electrode, the photoresist that adopts anhydrous propanone will remain in the CZT wafer surface is then peeled off together with the chromium billon that is deposited on this part photoresist, finally make the anode of little strip electrode pattern of two groups of coplanar interdigitals at the wafer top surface, referring to Fig. 1 and Fig. 2, the chromium electrode that is of being close to the cadmium zinc telluride crystal wafer surface, thickness is 50nm, be gold electrode above it, thickness is 500nm; The bar of little strip electrode of interdigital is wide to be 240 μ m; Every group of little strip electrode drawn with gold thread.
C. surface passivation:, need carry out passivation to the CZT surface that does not have depositing electrode in order to reduce the tracking current of device.Adopt KOH-KCl solution to carry out surface treatment earlier in the CZT sample for preparing electrode.The concentration of KOH and KCl solution is controlled at 15wt%, and the time is 40min; Then use the NH of 10wt% again
4F/H
2O
2Mixed solution carries out passivation, and the Passivation Treatment time is 10min; Then the CZT wafer being put into a large amount of deionized waters fully cleans to remove the various ions of remained on surface; Finally make coplanar grid anode tellurium-zinc-cadmium detector.
With the above-mentioned CZT coplane grid detector that makes, adopt the microcomputer multichannel spectrometer to test it and show in test result: compare with the CZT device of metal-semiconductor-metal (MSM) structure, the CZT device of common plane grid structure is right
57The radiogenic resolution of Co (122keV) has improved 50-80%, and is right
137The radiogenic resolution of Cs (662keV) has improved 70%-90%.
Because the difference of crystal mass, the coplane gate device of different crystal is compared with the MSM structure, and the amplitude difference that energy resolution improves is so provided the scope of above-mentioned energy resolution increase rate.
Claims (1)
1. the preparation method of a coplanar grid anode tellurium-zinc-cadmium detector, this detector is made up of tellurium-zincium-cadmium crystal and anode thereof and negative electrode, it is characterized in that the preparation method of this detector has following steps::
A. the surface treatment of tellurium-zincium-cadmium crystal: at first the cadmium zinc telluride crystal wafer of well cutting is slightly thrown with emery, clean subsequently, and put into the beaker sonic oscillation 5 minutes that fills deionized water, surface contamination that produces when removing thick throw and the foreign particle that is adsorbed on wafer surface, with the corundum powder polishing fluid cadmium zinc telluride crystal wafer is carefully thrown then, be minute surface until wafer surface; Remove surface impurity with sonic oscillation more subsequently, the cadmium zinc telluride crystal wafer after will polishing then is immersed in and carries out the surface chemistry corrosion in the BM corrosive liquid, and the time is 1-2 minute, and the BM corrosive liquid is the mixed solution of 5%Br and absolute methanol; To re-use LB corrosive liquid (2%Br+20% lactic acid+ethylene glycol) after the rinse in methyl alcohol through the wafer after the corrosion of BM corrosive liquid wafer is corroded, to increase the wafer surface smooth degree, the LB corrosive liquid is 2%Br, 20% lactic acid and ethylene glycol mixtures; The ultrasonic cleaning three times in methyl alcohol of the wafer of finishing corrosion, each time is 5-10 minute, to remove surperficial remaining Br and other impurity;
B. the preparation of electrode: will corrode good cadmium zinc telluride crystal wafer and take out, at N
2Dry up under the protective atmosphere, prepare preparation negative electrode and anode; Vacuum evaporation or electron beam evaporation method deposition chromium billon combination electrode are adopted in the preparation of negative electrode, and what be close to the tellurium-zincium-cadmium crystal lower surface is chromium electrode, is gold electrode on it; Negative electrode is made plane-shaped electrode, has gold or platinum to draw on this electrode; The preparation of anode is by MJB6 type litho machine, evenly apply one deck photoresist virgin rubber at the cadmium zinc telluride crystal wafer top surface, through behind the ultraviolet exposure, develop with 4-methyl-aqua ammonia aqueous solution and to obtain the electrode pattern of two groups of required interdigital, use vacuum evaporation afterwards, perhaps electron beam evaporation method deposits chromium billon combination electrode, the photoresist that adopts anhydrous propanone will remain in wafer surface is then peeled off together with the chromium billon that is deposited on this part photoresist, finally support the anode of little strip electrode pattern of two groups of coplanar interdigitals at the wafer top surface, the chromium electrode that is of being close to the tellurium-zincium-cadmium crystal surface, be gold electrode on it, every group of little strip electrode has spun gold or platinum line to draw;
C. surface passivation:, need carry out passivation to the plane of crystal that does not have depositing electrode in order to reduce the tracking current of device; The tellurium zinc chrome crystal that will prepare electrode earlier carries out surface treatment with KOH-KCl solution, then uses the NH of 10wt% again
4F/H
2O
2Mixed solution carries out passivation, and the Passivation Treatment time is 10-30 minute; The tellurium-zincium-cadmium crystal sample is put into a large amount of deionized waters fully to be cleaned to remove the various ions of remained on surface; Finally make coplanar grid anode tellurium-zinc-cadmium detector.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB200510023578XA CN1328598C (en) | 2005-01-26 | 2005-01-26 | Method for preparing coplanar grid anode tellurium-zinc-cadmium detector |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB200510023578XA CN1328598C (en) | 2005-01-26 | 2005-01-26 | Method for preparing coplanar grid anode tellurium-zinc-cadmium detector |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1648688A CN1648688A (en) | 2005-08-03 |
| CN1328598C true CN1328598C (en) | 2007-07-25 |
Family
ID=34875914
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CNB200510023578XA Expired - Fee Related CN1328598C (en) | 2005-01-26 | 2005-01-26 | Method for preparing coplanar grid anode tellurium-zinc-cadmium detector |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN1328598C (en) |
Families Citing this family (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102683490A (en) * | 2012-05-09 | 2012-09-19 | 上海大学 | Method for preparing In heavily-doped Au/In ohmic contact electrode on surface of cadmium zinc telluride crystal |
| CN103972323B (en) * | 2013-01-31 | 2017-05-03 | 同方威视技术股份有限公司 | Radiation detector |
| CN103165757B (en) * | 2013-03-29 | 2015-08-12 | 中国科学院半导体研究所 | Prepare the method for MSM structure C ZT detector |
| RU2705717C2 (en) * | 2014-12-17 | 2019-11-11 | Конинклейке Филипс Н.В. | Detector and method for detecting ionizing radiation |
| CN105244387B (en) * | 2015-11-23 | 2017-08-15 | 重庆大学 | A kind of photoconductive detector |
| CN107123698A (en) * | 2017-04-25 | 2017-09-01 | 西北工业大学 | CdZnTe planar detector surface treatment methods |
| CN110471100A (en) * | 2019-08-06 | 2019-11-19 | 西北工业大学 | Cadmium-zinc-teiluride pulse detector of interdigitated electrode structure and preparation method thereof |
| CN114242846B (en) * | 2022-02-25 | 2022-05-17 | 陕西迪泰克新材料有限公司 | Cadmium zinc telluride detector and grid passivation method thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6215123B1 (en) * | 1995-11-29 | 2001-04-10 | Simage Oy | Forming contacts on semiconductor substrates, radiation detectors and imaging devices |
| FR2836931A1 (en) * | 2002-03-05 | 2003-09-12 | Eurorad 2 6 | Production of semiconductive telluride crystals containing cadmium, zinc and/or selenium, used in a nuclear radiation detector, involves incorporation of iron, and Group III element(s) and using Travelling Solvent or Bridgman method |
| CN1547043A (en) * | 2003-12-11 | 2004-11-17 | 上海大学 | Microstrip particle detector and preparation method thereof |
-
2005
- 2005-01-26 CN CNB200510023578XA patent/CN1328598C/en not_active Expired - Fee Related
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US6215123B1 (en) * | 1995-11-29 | 2001-04-10 | Simage Oy | Forming contacts on semiconductor substrates, radiation detectors and imaging devices |
| FR2836931A1 (en) * | 2002-03-05 | 2003-09-12 | Eurorad 2 6 | Production of semiconductive telluride crystals containing cadmium, zinc and/or selenium, used in a nuclear radiation detector, involves incorporation of iron, and Group III element(s) and using Travelling Solvent or Bridgman method |
| CN1547043A (en) * | 2003-12-11 | 2004-11-17 | 上海大学 | Microstrip particle detector and preparation method thereof |
Non-Patent Citations (1)
| Title |
|---|
| CdZnTe核辐射探测器表面物理和化学钝化研究 金玮，桑文斌，李万万，葛艳辉，闵嘉华，张明龙，功能材料，第35卷第4期 2004 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN1648688A (en) | 2005-08-03 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN1328598C (en) | Method for preparing coplanar grid anode tellurium-zinc-cadmium detector | |
| Alimonti et al. | A large-scale low-background liquid scintillation detector: the counting test facility at Gran Sasso | |
| JP2000504832A (en) | Multimedia detector for medical images | |
| CN100485975C (en) | Coplanar gate anode tellurium-zinc-cadmium detector with capacitor gate and method for making same | |
| CN101459207B (en) | Manufacturing process for Au/Cr-CZT combination electrode | |
| CN109888051B (en) | X-ray detector and manufacturing method thereof | |
| CN103219399B (en) | Detecting element, radiation detector, medical treatment device and the method for generation detecting element | |
| CN107275440A (en) | A kind of method of nuclear detector tellurium-zinc-cadmium wafer surface passivation | |
| CN1320616C (en) | Surface passivation method for nuclear detector tellurium-zinc-cadmium wafer | |
| Mac Raighne et al. | Precision scans of the Pixel cell response of double sided 3D Pixel detectors to pion and X-ray beams | |
| Li et al. | Ultrasound‐Assisted Crystallization Enables Large‐Area Perovskite Quasi‐Monocrystalline Film for High‐Sensitive X‐ray Detection and Imaging | |
| Burger et al. | Characterization of large single-crystal gamma-ray detectors of cadmium zinc telluride | |
| US20030155515A1 (en) | Radiation detector with increased life span | |
| CN109087837A (en) | A kind of preparation method of streak camera photocathode | |
| CN103094405A (en) | Preparation process of CdZnTe detector of capacitive Frisch grid | |
| CN100587979C (en) | Method for making multi-crystal mercury iodide film room temperature nuclear irradiation detector | |
| Jones et al. | Study of surface passivation and Contact Deposition Techniques in CdZnTe X-Ray and gamma-ray detectors | |
| JP2013157494A (en) | Radiation detecting element, radiation detector and radiation detecting element manufacturing method | |
| CN207832676U (en) | A kind of sensor with surface-enhanced Raman effects | |
| CN110797457A (en) | Preparation method of multilayer storage structure transmission electron microscope in-situ electrical test unit | |
| CN110471100A (en) | Cadmium-zinc-teiluride pulse detector of interdigitated electrode structure and preparation method thereof | |
| EP1926146A2 (en) | Bi(12)MO(20) based Photo-conductor, radiation detector, and radiation imaging panel | |
| CN210040213U (en) | Low-cost optical detector | |
| CN104730559A (en) | Method for manufacturing planar nuclear radiation detector and portable nuclear radiation detecting device | |
| Yalamanchili et al. | Highly absorbing and high lifetime tapered silicon microwire arrays as an alternative for thin film crystalline silicon solar cells |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C06 | Publication | ||
| PB01 | Publication | ||
| C10 | Entry into substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| C17 | Cessation of patent right | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20070725 Termination date: 20110126 |