CN101483220A - Process for preparing phase-change memory - Google Patents
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- CN101483220A CN101483220A CNA200910045817XA CN200910045817A CN101483220A CN 101483220 A CN101483220 A CN 101483220A CN A200910045817X A CNA200910045817X A CN A200910045817XA CN 200910045817 A CN200910045817 A CN 200910045817A CN 101483220 A CN101483220 A CN 101483220A
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Abstract
本发明揭示了一种制备相变存储器的方法，包括：制备底层介质层的步骤；制备底层电极的步骤；制备标记图形的步骤；制备标记保护层的步骤；制备相变材料的步骤；制备刻蚀相变材料掩膜的步骤：利用自组装有序排列的聚苯乙烯微球做掩膜刻蚀相变材料；制备相变材料结构的步骤；基片平坦化处理步骤；顶层电极的引出步骤；顶层氧化硅沉积步骤。利用本发明中的自组装方式实现掩模时不受设备的限制，同时掩模面积也可以做到尽可能大，而且掩模的制备效率相对传统的方法要高的多。本发明相变存储器的制备方法有助于制备新型的高密度低功耗相变存储器，促进存储器的发展。
The invention discloses a method for preparing a phase-change memory, comprising: a step of preparing a bottom dielectric layer; a step of preparing a bottom electrode; a step of preparing a mark pattern; a step of preparing a mark protection layer; The steps of etching the phase change material mask: using self-assembled and ordered polystyrene microspheres as a mask to etch the phase change material; the step of preparing the phase change material structure; the step of planarizing the substrate; the step of leading out the top electrode ; Top silicon oxide deposition step. When using the self-assembly method in the present invention to realize the mask, it is not limited by equipment, and at the same time, the area of the mask can be made as large as possible, and the preparation efficiency of the mask is much higher than that of the traditional method. The preparation method of the phase-change memory of the invention is helpful for preparing a novel phase-change memory with high density and low power consumption, and promotes the development of the memory.
Description
Technical field
The invention belongs to microelectronic, relate to a kind of method for preparing phase transition storage, relate in particular to the orderly self-assembly microspheres of a kind of high density prepares phase transition storage as mask, in conjunction with chemico-mechanical polishing method.
Background technology
The basic conception of phase transition storage be Ovshinsky at first nineteen sixty-eight propose [, be based on the reversible transition of phase-change material, the low-resistance characteristic when the semiconductor high resistant characteristic when utilizing its amorphous state and polycrystalline attitude realizes the technology of storing.Very very long process has been experienced in the development of novel phase-change material and device preparation technology, be subjected to the restriction of material and device research and level of processing in the 1970s and 1980s, the power consumption of antetype device and speed can't be comparable with conventional semiconductor memory technologies, can not realize integrated with CM0S technology and function, thereby not cause international paying close attention to.Since the nineties, phase-change material and optics reversible transition The Characteristic Study thereof obtain important breakthrough, obtain develop rapidly in phase transformation optical storage application facet, and erasable HD-DVD phase change disc has been realized industrialization, has obtained huge commercial value.Rapid raising along with micro-nano process technology levels such as the development of integrated circuit technique, particularly photoetching utilizes the resistance characteristic of nanoscale phase-change material to realize that non-volatile memory technology has caused the attention of industrial quarters.Calendar year 2001, Intel has announced that capacity is the PCRAM pilot chip of 4Mb, its performance shows, when device feature size enters nanometer scale, PCRAM embodies than commercialization memory technology and the more superior comprehensive memory properties of novel memory technology such as FERAM and MRAM such as SRAM, DRAM and FLASH, be considered to the important breakthrough of solid state storage technologies behind FLASH, started the research boom of PCRAM memory technology in the world.
In micro-nano processing and semi-conductor industry, photoetching technique is the core of whole process flow, and the photolithography limitation size has determined the performance and the corresponding integrated level of entire semiconductor device.When photoetching technique entered 45nm and following size, the photoetching of large area region was restricted, and the raising of simultaneity factor integrated level also is difficult to solve.Need seek the mask technique that a kind of simple effective method is used as the following device of 45nm size based on this.The current micro nano structure new material that is assembled into the basis in order with single dispersion colloid microballoon has become a rising star in the advanced material family.Especially over past ten years along with the development of photonic crystal technology, become the most convenient form of research visible light and near infrared light wave band photonic crystal by the three-dimensional order periodic structure of colloid micro ball assembling.The potential application of micelle crystal of assembling is very extensive in order, can be used for making biological, chemical, optical sensor, optical filter and optical switch etc., the lattice constant of sub-micron micelle crystal and visible light, near-infrared wavelength are comparable in addition, therefore can be used for making the photonic crystal of visible and near infrared band.We find by experiment, and the etch rate of oxygen p-poly-phenyl ethene (PS) microballoon is very fast, and other gases that use in the semiconductor technology such as gases such as SF6, CHF3, CF4 are very slow to the etch rate of PS microballoon.Therefore the PS microballoon film that forms after the self assembly can be used for etching to subsurface material as mask.
In semi-conductor industry, integrated level is followed Moore's Law and scaling principle, quadruples with the integrated level every 3 years chips, and characteristic size is dwindled 1/3 speed development.In microelectronic technique, its surface roughness and surface smoothness become one of key factor that influences integrated circuit etching live width.At present, because reducing of the dwindling of device size, optical lithography equipment depth of focus requires the substrate surface evenness to reach nanoscale.IBM in 1991 first with the chemical Mechanical Polishing Technique successful Application in the production of 64Mb DRAM, various logic circuitry is moved towards CMP with memory with different development scales afterwards, CMP organically combines the abrasive action of nano particle and the chemical action of oxidant, has satisfied the leveling requirement of characteristic size below 0.35 μ m.The substrate of crossing through the CMP PROCESS FOR TREATMENT can reach the inaccessiable surface smoothness of other any plane processing technologys.At present, chemical Mechanical Polishing Technique has become the recognized standard leveling technology.
Summary of the invention
Technical problem to be solved by this invention is: provide the orderly self-assembly microspheres of a kind of high density to prepare the method for phase transition storage as mask, in conjunction with chemico-mechanical polishing, help to prepare novel high density low power consumption phase changing memory, promote the development of memory.
For solving the problems of the technologies described above, the present invention adopts following technical scheme:
A kind of method for preparing phase transition storage comprises the steps: to prepare the step of bottom dielectric layer; The step of preparation bottom electrode; The step of preparation marker graphic; The step of preparation mark protective layer; The step of preparation phase-change material; The step of preparation etching phase-change material mask: the polystyrene microsphere that utilizes self assembly to arrange is in order done the mask etching phase-change material; The step of preparation phase change material structure; Substrate planarization step; The top layer electrode draw step; Top layer silica deposition step.
As a preferred embodiment of the present invention, also comprised the cleaning silicon chip step before the step of preparation bottom dielectric layer: silicon chip is put into first solution boiled 3-10 minute, cooling deionized water rinsing 1-5 minute, then dries up with nitrogen; Wherein, described first solution is the mixed liquor of ammoniacal liquor, hydrogen peroxide, deionized water, ammoniacal liquor: hydrogen peroxide: deionized water=1:2:5; Silicon chip is put into second solution boiled 3-10 minute, cooling deionized water rinsing 1-5 minute, then dries up with nitrogen; Wherein, described second solution is the mixed liquor of hydrochloric acid, hydrogen peroxide, deionized water, hydrochloric acid: hydrogen peroxide: deionized water=1:2:5; Behind the cleaning silicon chip, silicon chip is toasted the moisture that 10min-60min removes the surface in 100 ℃-200 ℃ baking oven.
As a preferred embodiment of the present invention, in the step of preparation bottom dielectric layer, utilize the method for chemical vapour deposition (CVD) to prepare one deck SixN dielectric layer at silicon chip surface, its THICKNESS CONTROL is 300～500nm; Lower electrode is Al layer/Ti layer/TiN layer, and its THICKNESS CONTROL is 150nm/100nm/50nm; The THICKNESS CONTROL of alignment mark layer tungsten material is 200nm; The THICKNESS CONTROL of phase-change material layers is 100nm; Microballoon mask size Control after self assembly is arranged is below the 100nm; The THICKNESS CONTROL of silica medium layer is 100nm; The live width of focused ion beam extraction electrode is controlled to be below the 100nm; The THICKNESS CONTROL of top layer heat-insulating protective layer silica is 200nm.
As a preferred embodiment of the present invention, preparing of alignment mark figure uses the method for electron beam exposure association reaction ion etching to finish; The mark layer material uses tungsten, and the mark layer material thickness is controlled to be 200nm; Use negative resist during electron beam exposure, the resist THICKNESS CONTROL is 150nm.
As a preferred embodiment of the present invention, the mask preparation method of etching phase-change material utilizes the polystyrene microsphere of the orderly monolayer alignment of self assembly to finish after the oxygen etching reduces microsphere volume; The size Control of microballoon is below the 100nm, uninterruptedly utilizes the scanning electronic microscope observation microsphere surface to determine its size in the process implementing.
As a preferred embodiment of the present invention, the preparation of phase change material structure uses reactive ion etching to finish, and guarantees during etching that the region material that phase-change material layers does not have a mask protection is removed fully, deposits the silica medium layer of 100nm afterwards.
As a preferred embodiment of the present invention, the removal of the silica that deposits on remaining polystyrene microsphere and the microballoon uses CMP (Chemical Mechanical Polishing) process to finish; The control of the polishing degree of depth is as the criterion to remove remaining microballoon fully; Judge by the scanning electronic microscope observation surface condition by phased manner in the operational process of craft.
As a preferred embodiment of the present invention, drawing of top layer electrode utilizes the focused ion beam deposition alloy platinum material to finish, and the live width of electrode is controlled to be below the 100nm, and the thickness of electrode material is 100nm.
As a preferred embodiment of the present invention, the deposition of top layer heat-insulating protective layer silica utilizes the ion beam depositing method to finish, and the THICKNESS CONTROL of silica is 200nm.
A kind of method for preparing phase transition storage, this method comprises the preparation process of etching phase-change material mask: utilize the polystyrene microsphere of the orderly monolayer alignment of self assembly to do the mask etching phase-change material, finish after the oxygen etching reduces microsphere volume.
Beneficial effect of the present invention is:
Mask method traditional in the implementation method of the self assembly mask that relates among the present invention and the semiconductor technology has bigger improvement.
At first, the realization of traditional mask relates to various technology, and mask quality is subjected to the restriction of lithographic equipment performance simultaneously, and the size of its mask size also suffers restraints.Be not subjected to the restriction of equipment when utilizing self assembly mode among the present invention to realize mask, the mask area also can be accomplished greatly as far as possible simultaneously, and the traditional relatively method of the preparation efficiency of mask wants high many.
Secondly, the realization of self assembly mask is very low to the flatness requirement of substrate, and mask can rise and fall along with the pattern of substrate in the preparation process, can the precision of mask not impacted.Traditional photoetching requires very high to the degree of planarization of substrate, especially during electron beam lithography, because very shallow the need before electron beam exposure usually of the depth of focus of electron beam uses the method for chemico-mechanical polishing that planarization is carried out in substrate, realize more loaded down with trivial details on technology.
The 3rd, after self assembly realized mask, mask size can utilize the method for oxygen etching to realize as required, realized comparatively simply on the technology, can realize the large-area mask preparation that 50nm is following easily; Traditional photoetching technique is difficult to accomplish the preparation of the large tracts of land mask below the 50nm now.
The 4th, mask cost aspect, the cost of self assembly mask is extremely low, compares with the photoetching cost and almost can ignore.
The 5th, when mask was removed the planarization base treatment, the self-assembly microspheres mask was because less with the contact area of substrate, and adhesive force is little, so be easy to remove the especially easier realization of substrate planarization behind the sputter material on the microballoon mask.
The preparation method of phase transition storage of the present invention helps to prepare novel high density low power consumption phase changing memory, promotes the development of memory.
Description of drawings
Fig. 1 is the structural representation of step 2 back phase transition storage.
Fig. 2 is the structural representation of step 3 back phase transition storage.
Fig. 3 A is the end view of phase transition storage behind deposits tungsten and the electron beam exposure.
Fig. 3 B is the vertical view of Fig. 3 A.
Fig. 3 C is the end view of phase transition storage after the mark layer material etching.
Fig. 3 D is the vertical view of Fig. 3 C.
Fig. 4 is the structural representation of step 5 back phase transition storage.
Fig. 5 is the structural representation of step 6 back phase transition storage.
Fig. 6 is the structural representation of step 7 back phase transition storage.
Fig. 7 is the structural representation of step 8 back phase transition storage.
Fig. 8 is the structural representation of step 9 back phase transition storage.
Fig. 9 is the structural representation of step 10 back phase transition storage.
Embodiment
Describe the preferred embodiments of the present invention in detail below in conjunction with accompanying drawing.
Embodiment one
See also Fig. 1-Fig. 9, the present invention has disclosed the orderly self-assembly microspheres of a kind of high density as mask, prepare the method for phase transition storage in conjunction with chemico-mechanical polishing, specifically comprises the steps:
[step 1] silicon chip substrate is cleaned.
With silicon chip put into 1# liquid (mixture of ammoniacal liquor, hydrogen peroxide, deionized water, ammoniacal liquor: hydrogen peroxide: boiled 5 minutes in the deionized water=1:2:5), cooling, deionized water rinsing 3 minutes, nitrogen dries up then.Main effect: greasy dirt and the bulky grain of removing silicon face.
With silicon chip put into 2# liquid (mixture of hydrochloric acid, hydrogen peroxide, deionized water, hydrochloric acid: hydrogen peroxide: clean in the deionized water=1:2:5), method is with the cleaning method of above-mentioned 1# liquid; Main effect is a metal ion of removing silicon chip surface.
Silicon chip is toasted the moisture that 30min removes the surface in 120 ℃ baking oven.
The preparation of [step 2] bottom dielectric layer.
The method of utilizing chemical vapour deposition (CVD) deposition one layer thickness on the clean silicon chip of aforementioned processing is the SixN (as shown in Figure 1) of 300～500nm.
The preparation of [step 3] bottom electrode.
Utilize the method for magnetron sputtering to form bottom electrode Al/Ti/TiN, its corresponding thickness is controlled to be 150nm/100nm/50nm (as shown in Figure 2).
The preparation of [step 4] marker graphic.
The method deposit thickness that utilizes magnetron sputtering is the tungsten of the 200nm layer material that serves as a mark.Spin coating negative resist SU8, the resist THICKNESS CONTROL is 150nm; Utilize electron beam exposure to make marker graphic, on the tungsten material, etching depth is controlled to be 200nm (shown in Fig. 3 A-3D) through reactive ion etching metastatic marker figure.
[step 5] preparation mark protective layer.
Marker graphic is not impacted when guaranteeing the etching phase-change material, need and to prepare layer protective layer on the marker graphic.Utilize the uv-exposure negative photoresist herein, thereby make and keep the purpose that one deck photoresist reaches the protection marker graphic on the marker graphic, the photoresist THICKNESS CONTROL is 300nm (as shown in Figure 4).
The preparation of [step 6] phase-change material.
Utilize the method sediment phase change material of magnetron sputtering, THICKNESS CONTROL is 100nm (as shown in Figure 5).
The preparation of [step 7] etching phase-change material mask.Utilize the polystyrene microsphere of the orderly monolayer alignment of self assembly after the oxygen etching reduces microsphere volume, to finish.The size Control of microballoon is below the 100nm, can uninterruptedly utilize the scanning electronic microscope observation microsphere surface to determine its size (as shown in Figure 6) in the process implementing.
The preparation of [step 8] phase change material structure.
The preparation of phase change material unit utilizes reactive ion etching to finish, and guarantees during etching that the region material that phase-change material layers does not have a mask protection is removed fully, deposits the silica medium layer (as shown in Figure 7) of 100nm afterwards.
[step 9] substrate planarization.
Planarization is mainly removed polystyrene microsphere remaining after the etching and is deposited on silica on the microballoon, and this technology utilizes chemical mechanical polishing method to finish herein.The control of the polishing degree of depth is as the criterion to remove remaining microballoon fully.Can judge (as shown in Figure 8) by the scanning electronic microscope observation surface condition by phased manner in the operational process of craft.
Drawing of [step 10] top layer electrode.
The deposition of top layer electrode utilizes the focused ion beam deposition alloy platinum material to finish.The live width of electrode is controlled to be below the 100nm, and the thickness of electrode material is 100nm (as shown in Figure 9).
[step 11] top layer silica deposition.
The deposition of top layer heat-insulating protective layer silica utilizes the ion beam depositing method to finish.The THICKNESS CONTROL of silica is 200nm.
Mask method traditional in the implementation method of the self assembly mask that relates among the present invention in sum, and the semiconductor technology has bigger improvement.
At first, the realization of traditional mask relates to various technology, and mask quality is subjected to the restriction of lithographic equipment performance simultaneously, and the size of its mask size also suffers restraints.Be not subjected to the restriction of equipment when utilizing self assembly mode among the present invention to realize mask, the mask area also can be accomplished greatly as far as possible simultaneously, and the traditional relatively method of the preparation efficiency of mask wants high many.
Secondly, the realization of self assembly mask is very low to the flatness requirement of substrate, and mask can rise and fall along with the pattern of substrate in the preparation process, can the precision of mask not impacted.Traditional photoetching requires very high to the degree of planarization of substrate, especially during electron beam lithography, because very shallow the need before electron beam exposure usually of the depth of focus of electron beam uses the method for chemico-mechanical polishing that planarization is carried out in substrate, realize more loaded down with trivial details on technology.
The 3rd, after self assembly realized mask, mask size can utilize the method for oxygen etching to realize as required, realized comparatively simply on the technology, can realize the large-area mask preparation that 50nm is following easily; Traditional photoetching technique is difficult to accomplish the preparation of the large tracts of land mask below the 50nm now.
The 4th, mask cost aspect, the cost of self assembly mask is extremely low, compares with the photoetching cost and almost can ignore.
The 5th, when mask was removed the planarization base treatment, the self-assembly microspheres mask was because less with the contact area of substrate, and adhesive force is little, so be easy to remove the especially easier realization of substrate planarization behind the sputter material on the microballoon mask.
The preparation method of phase transition storage of the present invention helps to prepare novel high density low power consumption phase changing memory, promotes the development of memory.
Embodiment two
In the present embodiment, the orderly self-assembly microspheres of above-specified high density comprises the steps: as mask, the method for preparing phase transition storage in conjunction with chemico-mechanical polishing
1, on the silicon chip of (100) orientation, the method for applied chemistry vapour deposition at first prepares one deck SixN dielectric layer, and its THICKNESS CONTROL is 300～500nm;
2, use the thick Al/Ti/TiN of method deposition 300nm of magnetron sputtering then, each layer respective thickness is 150nm/100nm/50nm, as the bottom electrode material, and the tungsten that magnetron sputtering 200nm is thick on the bottom electrode material layer material that serves as a mark;
3, utilize the ion etching of electron beam lithography association reaction to form marker graphic, as the basis of follow-up lithography alignment;
4, utilize the ultraviolet photolithographic method unaffected in order to protect in the etching of alignment patterns at phase-change material in forming one deck photoresist figure on the marker material;
5, utilize the phase-change material of the method deposit thickness of magnetron sputtering for 100nm on the bottom electrode material, the mask of one deck polystyrene microsphere as the etching phase-change material arranged in self assembly afterwards uniform sequentially;
6, at first use oxygen that microsphere volume is reduced before the etching phase-change material, this purpose is in order to make that between the unit that forms after the phase-change material etching all be relatively independent, to be independent of each other;
7, utilize reactive ion (RIE) etching phase-change material to form independently array element, its cell size is controlled to be below the 100nm;
8, after the phase-change material etching is finished, use carbon tetrachloride reagent, acetone reagent, ethanol reagent, deionized water successively, in weak ultrasound environments, cleaned sample 5 minutes, in 100 ℃ of baking ovens sample is dried then, then use the ion beam depositing legal system to be equipped with the silica of 100nm thickness as dielectric layer;
9, utilize chemical mechanical polishing method to remove the above part of phase-change material layers, comprise the silica medium layer that deposits on microballoon mask remaining after the etching and the microballoon;
10, utilize focused ion beam to draw upper electrode, after upper electrode was drawn, ion beam depositing method sputter thickness was that the silica of 200nm is as heat-insulating protective layer.
Here description of the invention and application is illustrative, is not to want with scope restriction of the present invention in the above-described embodiments.Here the distortion of disclosed embodiment and change are possible, and the various parts of the replacement of embodiment and equivalence are known for those those of ordinary skill in the art.Those skilled in the art are noted that under the situation that does not break away from spirit of the present invention or substantive characteristics, and the present invention can be with other forms, structure, layout, ratio, and realize with other elements, material and parts.Under the situation that does not break away from the scope of the invention and spirit, can carry out other distortion and change here to disclosed embodiment.
As, in the preparation process of etching phase-change material mask, can utilize other microballoons except that polystyrene microsphere to do the mask etching phase-change material, as long as it is of the required size.
Claims (10)
1, a kind of method for preparing phase transition storage is characterized in that, comprises the steps:
The step of preparation bottom dielectric layer;
The step of preparation bottom electrode;
The step of preparation marker graphic;
The step of preparation mark protective layer;
The step of preparation phase-change material;
The step of preparation etching phase-change material mask: the microballoon that utilizes self assembly to arrange is in order done mask etching
Phase-change material;
The step of preparation phase change material structure;
Substrate planarization step;
The top layer electrode draw step;
Top layer silica deposition step.
2, the method for preparing phase transition storage according to claim 1 is characterized in that:
Before the step of preparation bottom dielectric layer, also comprise the cleaning silicon chip step:
Silicon chip is put into first solution boiled 3-10 minute, cooling deionized water rinsing 1-5 minute, then dries up with nitrogen; Wherein, described first solution is the mixed liquor of ammoniacal liquor, hydrogen peroxide, deionized water, and the ratio of ammoniacal liquor, hydrogen peroxide, deionized water is 1:2:5;
Silicon chip is put into second solution boiled 3-10 minute, cooling deionized water rinsing 1-5 minute, then dries up with nitrogen; Wherein, described second solution is the mixed liquor of hydrochloric acid, hydrogen peroxide, deionized water, and the ratio of hydrochloric acid, hydrogen peroxide, deionized water is 1:2:5;
Behind the cleaning silicon chip, silicon chip is toasted the moisture that 10min-60min removes the surface in 100 ℃-200 ℃ baking oven.
3, the method for preparing phase transition storage according to claim 1 is characterized in that:
In the step of described preparation bottom dielectric layer, utilize the method for chemical vapour deposition (CVD) to prepare one deck SixN dielectric layer at silicon chip surface, its THICKNESS CONTROL is 300～500nm.
4, the method for preparing phase transition storage according to claim 1 is characterized in that:
In the step of described preparation alignment mark figure, use the method for electron beam exposure association reaction ion etching to finish; The mark layer material uses tungsten; Use negative resist during electron beam exposure.
5, the method for preparing phase transition storage according to claim 1 is characterized in that:
In the step of described preparation etching phase-change material mask, utilize the polystyrene microsphere of the orderly monolayer alignment of self assembly after the oxygen etching reduces microsphere volume, to finish;
The size Control of microballoon is below the 100nm, uninterruptedly utilizes the scanning electronic microscope observation microsphere surface to determine its size in the process implementing.
6, the method for preparing phase transition storage according to claim 1 is characterized in that:
In the step of described preparation phase change material structure, use reactive ion etching to finish, guarantee during etching that the region material that phase-change material layers does not have a mask protection is removed fully, afterwards the cvd silicon oxide dielectric layer.
7, the method for preparing phase transition storage according to claim 1 is characterized in that:
The removal of the silica that deposits on remaining polystyrene microsphere and the microballoon uses CMP (Chemical Mechanical Polishing) process to finish;
The control of the polishing degree of depth is as the criterion to remove remaining microballoon fully;
Judge by the scanning electronic microscope observation surface condition by phased manner in the operational process of craft.
8, the method for preparing phase transition storage according to claim 1 is characterized in that:
Drawing in the step of top layer electrode utilizes the focused ion beam deposition alloy platinum material to finish, and the live width of electrode is controlled to be below the 100nm.
9, the method for preparing phase transition storage according to claim 1 is characterized in that:
The deposition of top layer heat-insulating protective layer silica utilizes the ion beam depositing method to finish.
10, a kind of method for preparing phase transition storage is characterized in that:
This method comprises the preparation process of etching phase-change material mask: utilize the microballoon of the orderly monolayer alignment of self assembly to do the mask etching phase-change material, finish after the oxygen etching reduces microsphere volume.
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102593357A (en) * | 2012-03-31 | 2012-07-18 | 中国科学院上海微系统与信息技术研究所 | Method for preparing phase change memory with nano memory performance |
| CN103091981A (en) * | 2013-01-10 | 2013-05-08 | 中国科学院半导体研究所 | Method for manufacturing metal grid template for photolithography by utilizing self-assembling ball |
| CN103515484A (en) * | 2013-09-13 | 2014-01-15 | 南开大学 | Textured transparent conductive thin film with periodic structure and preparation method thereof |
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| CN115275001A (en) * | 2022-06-28 | 2022-11-01 | 中国科学院上海微系统与信息技术研究所 | A kind of preparation method of high density phase change memory |
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2009
- 2009-01-23 CN CNA200910045817XA patent/CN101483220A/en active Pending
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN102593357A (en) * | 2012-03-31 | 2012-07-18 | 中国科学院上海微系统与信息技术研究所 | Method for preparing phase change memory with nano memory performance |
| CN102593357B (en) * | 2012-03-31 | 2013-10-30 | 中国科学院上海微系统与信息技术研究所 | Method for preparing phase change memory with nano memory performance |
| CN103091981A (en) * | 2013-01-10 | 2013-05-08 | 中国科学院半导体研究所 | Method for manufacturing metal grid template for photolithography by utilizing self-assembling ball |
| CN103091981B (en) * | 2013-01-10 | 2014-08-13 | 中国科学院半导体研究所 | Method for manufacturing metal grid template for photolithography by utilizing self-assembling ball |
| CN103515484A (en) * | 2013-09-13 | 2014-01-15 | 南开大学 | Textured transparent conductive thin film with periodic structure and preparation method thereof |
| CN103515484B (en) * | 2013-09-13 | 2015-08-19 | 南开大学 | Matte transparent conductive film of a kind of periodic structure and preparation method thereof |
| CN104698742A (en) * | 2013-12-10 | 2015-06-10 | 上海微电子装备有限公司 | Manufacturing method of nano patterned sapphire substrate (PSS) structure |
| CN115275001A (en) * | 2022-06-28 | 2022-11-01 | 中国科学院上海微系统与信息技术研究所 | A kind of preparation method of high density phase change memory |
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