Disclosure of Invention
The invention aims to provide a metal sheet packaging method of an embedded memory chip in a space environment satellite, and aims to provide a radiation-resistant memory chip, wherein a radiation-enhanced corrosion-resistant coating is coated on a metal substrate, and a radiation-resistant shell with strong moisture resistance and corrosion resistance is formed outside the memory chip so as to prolong the service life of the memory chip.
The aim of the invention can be achieved by the following technical scheme:
the invention aims to provide a metal sheet packaging method of an embedded memory chip in a space environment satellite, which comprises the following steps:
pretreating the surface of a base metal material;
preparing raw materials of a radiation enhanced corrosion resistant layer, wherein the radiation enhanced corrosion resistant layer comprises the following raw materials in parts by weight:
10-20 parts of siloxane modified graphene, 5-10 parts of zinc oxide, 5-10 parts of tin oxide, 20-30 parts of methyltrimethoxysilane, 0.5-3 parts of formic acid, 0.5-2.5 parts of dispersing auxiliary and 8-28 parts of deionized water;
uniformly mixing the siloxane modified graphene, zinc oxide, tin oxide, a dispersing aid and deionized water in parts by weight, adding methyltrimethoxysilane and formic acid, grinding at room temperature, filtering, spraying on the surface of a pretreated base metal material, drying, and curing to obtain a metal sheet with a radiation enhanced corrosion resistant layer coated on the surface;
the metal sheet coated with the radiation-enhanced corrosion-resistant layer on the surface is processed into a radiation-resistant shell, and then the radiation-resistant shell is packaged on the surface of the embedded memory chip.
Further, the base metal material is an aluminum base metal plate or a copper base metal plate, and the thickness of the base metal material is 1-5mm.
Further, the siloxane modified graphene is prepared by grafting reaction of hyperbranched siloxane formed by hydrolyzing an aminosilane coupling agent under an acidic condition and graphene oxide in a mixed solvent of ethanol and deionized water under an alkaline condition.
Further, the reaction temperature of the grafting reaction is 70-80 ℃, the reaction time is 1-24h, and the alkaline condition is that the pH is 9-10.
Further, the mass ratio of hyperbranched siloxane to graphene oxide in the grafting reaction is 1:0.02-0.1.
Further, in the reaction of hydrolyzing the aminosilane coupling agent under an acidic condition to form hyperbranched siloxane, the mass ratio of the aminosilane coupling agent to deionized water is 2:6-10.
Further, the acidic condition is that the pH is 5-5.5, the reaction temperature is 50-60 ℃ and the reaction time is 1-12h in the hydrolysis reaction.
Further, the particle size of the zinc oxide is 10-20 mu m, and the particle size of the tin oxide is 1-20 mu m.
Further, the curing temperature is 200-250 ℃ and the curing time is 10-20min.
Further, the radiation enhanced corrosion resistant layer has a thickness of 10-30 μm.
The invention has the beneficial effects that:
the invention provides a metal sheet packaging method of an embedded memory chip in a space environment satellite, which adopts a method of coating a radiation-enhanced corrosion-resistant coating on a metal substrate, and utilizes the radiation resistance of the metal substrate and the radiation resistance of the radiation-enhanced corrosion-resistant coating, and realizes the radiation resistance of a light metal substrate by the combination of a thin metal sheet and a thin metal sheet surface coating;
the radiation-enhanced corrosion-resistant coating is formed by grafting reaction of hyperbranched siloxane and graphene oxide, wherein the hyperbranched siloxane is used as an auxiliary dispersing agent of zinc oxide and tin oxide in the coating, has good compatibility with methyltrimethoxysiloxane, can continuously participate in hydrolysis reaction in the coating forming process, and bonds the radiation-enhanced filler in an interpenetrating network of the coating, so that the radiation-enhanced filler is dispersed in the coating more uniformly, and finally the radiation-enhanced corrosion-resistant coating is an organic silicon coating (formed by hydrolysis of methyltrimethoxysiloxane) and has high temperature resistance, corrosion resistance and moisture resistance;
in summary, the radiation-enhanced corrosion-resistant coating is coated on the metal substrate, and the radiation-resistant shell is packaged on the surface of the embedded memory chip, so that the radiation-resistant purpose of the light metal substrate is achieved, and the corrosion resistance and the humidity resistance of the radiation-resistant shell are improved.
Detailed Description
The technical solutions of the embodiments of the present invention will be clearly and completely described below in conjunction with the embodiments of the present invention, and it is apparent that the described embodiments are only some embodiments of the present invention, not all embodiments. All other embodiments, which can be made by those skilled in the art based on the embodiments of the invention without making any inventive effort, are intended to be within the scope of the invention.
According to the embodiment of the invention, the metal sheet packaging method of the embedded storage chip in the space environment satellite comprises the following steps:
firstly, preprocessing the surface of a base metal material;
secondly, preparing raw materials of a radiation enhanced corrosion resistant layer, wherein the radiation enhanced corrosion resistant layer comprises the following raw materials in parts by weight:
10-20 parts of siloxane modified graphene, 5-10 parts of zinc oxide, 5-10 parts of tin oxide, 20-30 parts of methyltrimethoxysilane, 0.5-3 parts of formic acid and 8-28 parts of deionized water;
step three, uniformly mixing siloxane modified graphene, zinc oxide, tin oxide, a dispersing aid and deionized water, adding methyltrimethoxysilane and formic acid, grinding at room temperature, filtering, spraying on the surface of the pretreated base metal material, drying, and curing to obtain a metal sheet with a radiation enhanced corrosion resistant layer coated on the surface;
and fourthly, processing the metal sheet with the surface coated with the radiation-enhanced corrosion-resistant layer into a radiation-resistant shell, and then packaging the radiation-resistant shell on the surface of the embedded memory chip.
In the first step, the base metal material is an aluminum base metal plate or a copper base metal plate, and the thickness of the base metal material is 1-5mm;
specifically, the thickness of the base metal material may be 1mm, 2mm, 3mm, 4mm, or 5mm.
In the first step, the pretreatment of the surface of the base metal material includes polishing and cleaning the surface of the metal plate, and the polishing and cleaning operations are common knowledge in the art, and the present invention is not described herein.
In the second step, the siloxane modified graphene is prepared by grafting reaction of hyperbranched siloxane formed by hydrolyzing an aminosilane coupling agent under an acidic condition and graphene oxide in a mixed solvent of ethanol and deionized water under an alkaline condition.
In the second step, the reaction temperature of the grafting reaction is 70-80 ℃, the reaction time is 1-24h, and the alkaline condition is that the pH is 9-10; the mass ratio of hyperbranched siloxane to graphene oxide in the grafting reaction is 1:0.02-0.1;
specifically, the grafting reaction has a reaction temperature of 70 ℃, 71 ℃, 72 ℃, 73 ℃, 74 ℃, 75 ℃, 76 ℃, 77 ℃, 78 ℃, 79 ℃ or 80 ℃;
the reaction time of the grafting reaction is 1h, 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, 10h, 11h, 12h, 13h, 14h, 15h, 16h, 17h, 18h, 19h, 20h, 21h, 22h, 23h or 24h;
the mass ratio of hyperbranched siloxane to graphene oxide in the grafting reaction is 1:0.02, 1:0.03, 1:0.04, 1:0.05, 1:0.06, 1:0.07, 1:0.08, 1:0.09 or 1:0.1.
In the second step, in the reaction of hydrolyzing the aminosilane coupling agent under an acidic condition to form hyperbranched siloxane, the mass ratio of the aminosilane coupling agent to deionized water is 2:6-10; the pH is 5-5.5, the reaction temperature is 50-60 ℃ and the reaction time is 1-12h in the hydrolysis reaction;
the mass ratio of the aminosilane coupling agent to the deionized water is 2: 6. 2: 7. 2: 8. 2:9 or 2:10;
the reaction temperature of the hydrolysis is 50 ℃, 51 ℃, 52 ℃, 53 ℃, 54 ℃, 55 ℃, 56 ℃, 57 ℃, 58 ℃, 59 ℃ or 60 ℃;
the reaction time of the hydrolysis is 1h, 2h, 3h, 4h, 5h, 6h, 7h, 8h, 9h, 10h, 11h or 12h.
In the second step, the particle size of the zinc oxide is 10-20 mu m, and the particle size of the tin oxide is 1-20 mu m;
the zinc oxide has a particle size of 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, 15 μm, 16 μm, 17 μm, 18 μm, 19 μm or 20 μm;
the particle size of the tin oxide is 1 μm, 2 μm, 3 μm, 4 μm, 5 μm, 6 μm, 7 μm, 8 μm, 9 μm, 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, 15 μm, 16 μm, 17 μm, 18 μm, 19 μm or 20 μm.
In the third step, the thickness of the radiation enhanced corrosion resistant layer is 10-30 mu m;
the radiation enhanced corrosion resistant layer has a thickness of 10 μm, 11 μm, 12 μm, 13 μm, 14 μm, 15 μm, 16 μm, 17 μm, 18 μm, 19 μm, 20 μm, 21 μm, 22 μm, 23 μm, 24 μm, 25 μm, 26 μm, 27 μm, 28 μm, 29 μm, 30 μm.
In the third step, the curing temperature is 200-250 ℃ and the curing time is 10-20min;
the curing temperature is 200 ℃, 220 ℃, 230 ℃, 240 ℃, or 250 ℃;
the curing time is 10min, 11min, 12min, 13min, 14min, 15min, 16min, 17min, 18min, 19min or 20min.
1. Preparation of raw materials
Example 1
Preparation of siloxane modified graphene
A1, after 2g of aminosilane coupling agent is ultrasonically dispersed in 8g of deionized water, the pH value of the mixed solution is regulated to 5-5.5 by concentrated hydrochloric acid, the mixed solution is heated to the reaction temperature of 860 ℃, the reaction is carried out by heat preservation and heating, the reaction time is 8h, and the hyperbranched siloxane is obtained by vacuum rotary evaporation
A2, uniformly mixing 10g of hyperbranched siloxane prepared by the method and 0.8g of graphene oxide in a mixed solvent of 50mL of ethanol and 50mL of deionized water, heating to a reaction temperature of 75 ℃ under the condition of pH of 9-10, preserving heat for reaction for 16 hours, and carrying out suction filtration and cleaning with ethanol for three times to obtain the siloxane modified graphene.
Example 2
Metal sheet package of embedded memory chip in space environment satellite
The encapsulation was performed according to the encapsulation method provided in the above example, in which the raw materials of the radiation-enhanced corrosion-resistant layer were prepared according to table 1, and the base metal material was a 3mm aluminum base metal plate.
Table 1 (weight portions)
The encapsulated embedded memory chips obtained in example 2 are labeled example 2-1, example 2-2, example 2-3, example 2-4, example 2-5, example 2-6, example 2-7, example 2-8 and example 2-9, and the thicknesses of the resulting radiation enhanced radio-corrosion resistant layers are shown in table 2.
Performance test:
the packaged-processed embedded memory chip obtained in example 2, the unpackaged embedded memory chip (as a blank test group, comparative example 1) and the unpackaged metal-sheet-packaged embedded memory chip (as a blank test group, comparative example 2) were subjected to cumulative radiation resistance test together, and the obtained results are shown in table 2.
Corrosion resistance test: the metal sheet coated with the radiation-enhanced corrosion-resistant layer and the uncoated metal sheet (as a blank test group, comparative example 3) obtained in the third step of example 2 were subjected to a salt spray test under the following specific conditions: JIS2371 salt spray test for 200 hours, the weight loss rate was measured, and the test results are shown in Table 2;
TABLE 2
As can be seen from the data in table 2, the radiation resistance of the packaged-processed embedded memory chip in this example 2 is superior to that of the untreated embedded memory chip and the uncoated metal sheet packaged-processed embedded memory chip.
In the description of the present specification, the descriptions of the terms "one embodiment," "example," "specific example," and the like, mean that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present invention. In this specification, schematic representations of the above terms do not necessarily refer to the same embodiments or examples. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples.
The foregoing is merely illustrative and explanatory of the invention, as various modifications and additions may be made to the particular embodiments described, or in a similar manner, by those skilled in the art, without departing from the scope of the invention or exceeding the scope of the invention as defined in the claims.