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CN117757341B - Anti-radiation processing method for embedded memory chip in space environment satellite - Google Patents

Anti-radiation processing method for embedded memory chip in space environment satellite Download PDF

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Publication number
CN117757341B
CN117757341B CN202311854449.XA CN202311854449A CN117757341B CN 117757341 B CN117757341 B CN 117757341B CN 202311854449 A CN202311854449 A CN 202311854449A CN 117757341 B CN117757341 B CN 117757341B
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radiation
memory chip
embedded memory
powder
space environment
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CN117757341A (en
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李修录
尹善腾
朱小聪
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Axd Anxinda Memory Technology Co ltd
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Axd Anxinda Memory Technology Co ltd
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Abstract

The invention relates to a radiation-resistant processing method of an embedded memory chip in a space environment satellite, and belongs to the technical field of radiation-resistant processing of chips. The method comprises the following steps: a raw material provided with a radiation-resistant coating, the radiation-resistant coating comprising the following raw materials: barium sulfate, binding resin, rui Qin powdery mildew and curing agent; mixing and grinding barium sulfate, binding resin and Ruiki powder to obtain powder, adding a curing agent into the powder, spraying the powder on the surface of the chip obtained by the surface treatment, and curing to obtain a radiation-resistant coating; the bonding resin is formed by hyperbranched reaction of dioxy-terminated siloxane and triol under alkaline conditions. The powder adopts radiation-resistant coating, and forms a layer of ultrathin radiation-resistant coating on the surface of the embedded memory chip, so that the corrosion resistance of the memory chip is enhanced, and the electrical property of the memory chip is not affected.

Description

Anti-radiation processing method for embedded memory chip in space environment satellite
Technical Field
The invention belongs to the technical field of radiation-resistant processing of chips, and particularly relates to a radiation-resistant processing method of an embedded memory chip in a space environment satellite.
Background
With the development of nuclear and space technology, a large number of electronic devices and systems are being put into operation in nuclear reaction radiation and other nuclear environments. Neutrons, y-rays and nuclear electromagnetic pulses generated during nuclear reactions, electrons, protons and energetic particles in the space radiation can cause damage to electronic devices and electronic systems. Among them, the single event effect found in 1975 is an important nuclear radiation effect: the soft error of the semiconductor device is mainly caused by high-energy protons, neutrons, alpha particles, heavy particles and the like, and the soft error has become an important factor for influencing the stability of the micro-application devices running in an orbit system. Therefore, a method of reinforcing the chip is generally adopted for the purpose of resisting the single particle radiation. But with the reinforcement method, the performance of the chip is generally reduced and the power consumption is increased. Therefore, for the radiation-resistant treatment of the chip, the radiation-resistant treatment method of the embedded storage chip in the space environment satellite is provided, the radiation-resistant reinforced chip is replaced by the common industrial chip without the radiation-resistant effect, and the problem of low radiation resistance of the common industrial chip without the radiation-resistant effect is solved, so that the radiation-resistant treatment method is a key for solving the problems of reduced performance and increased power consumption of the radiation-resistant reinforced chip.
Disclosure of Invention
The invention aims to provide a radiation-resistant processing method for an embedded memory chip in a space environment satellite.
The aim of the invention can be achieved by the following technical scheme:
a radioresistant processing method of an embedded memory chip in a space environment satellite comprises the following steps:
The anti-radiation coating comprises the following raw materials in percentage by weight: 35-55% of barium sulfate, 20-45% of binding resin, 15-25% of Qin powdery mildew and 0.4-1.5% of curing agent;
mixing and grinding barium sulfate, binding resin and Ruiki powder to obtain powder, adding a curing agent into the powder, spraying the powder on the surface of the chip obtained by the surface treatment, and curing to obtain a radiation-resistant coating;
The bonding resin is formed by hyperbranched reaction of dioxy-terminated siloxane and triol under alkaline conditions;
the molecular structural formula of the dioxy terminated siloxane is shown as a formula (1):
the molecular structural formula of the triol is shown as formula (2):
Further, the solvent used in the hyperbranched reaction is one of organic ether solvents.
Further, the molar ratio of the dioxy-terminated siloxane to the triol is 3-4:2, preferably 3:2.
Further, the reaction temperature of the hyperbranched reaction is 50-65 ℃ and the reaction time is 4-24h.
Further, the dioxy terminated siloxane is formed by hydrosilylation reaction of tetramethyl dihydro siloxane and allyl alcohol glycidyl ether under the catalysis of a platinum catalyst.
Further, the molar ratio of the tetramethyl dihydro siloxane to the allyl alcohol glycidyl ether is 1:2-2.3.
Further, the hydrosilylation reaction temperature is 55-66 ℃ and the reaction time is 8-30h.
Further, the triol is formed from [3- (trimethoxysilyl) propyl ] succinic anhydride and tris-hydroxymethyl-aminomethane in a first solvent via reaction of an amino group and an anhydride.
Further, the molar ratio of the triol to the tris [3- (trimethoxysilyl) propyl ] succinic anhydride to the tris is 1:1-1.3, wherein the first solvent is ethanol, and the reaction temperature of the triol is 60-70 ℃ and the reaction time is 3-24h, wherein the reaction temperature of the triol is [3- (trimethoxysilyl) propyl ] succinic anhydride and the reaction time of the trimethylol aminomethane.
Further, the curing agent is one of amine curing agents, and the invention is not particularly limited to a specific amine curing agent.
Further, the thickness of the radiation-resistant coating is 5-15 mu m.
The invention has the beneficial effects that:
the invention provides a radiation-resistant treatment method for an embedded memory chip in a space environment satellite, which adopts radiation-resistant coating, forms a layer of ultrathin radiation-resistant coating on the surface of the embedded memory chip, wherein the thickness of the coating is 5-15 mu m, and carries out a temperature-changing test and examination test at-55-125 ℃ on the obtained radiation-resistant embedded memory chip, so that the result shows that the elastic radiation-resistant coating is well matched with the linear expansion coefficients of the chip and an inner lead, and the phenomena of inner lead disconnection and bonding failure caused by different linear expansion coefficients do not occur;
Meanwhile, the obtained anti-radiation embedded memory chip and the embedded memory chip which is not subjected to anti-radiation treatment are subjected to anti-radiation test, and the result shows that the anti-radiation dosage of the anti-radiation embedded memory chip is obviously changed before and after the anti-radiation coating is coated, the anti-radiation dosage of the coated embedded memory chip is almost increased by two orders of magnitude, and other electrical performances of the embedded memory chip are not influenced;
in summary, the invention adopts radiation-resistant coating to form a layer of ultrathin radiation-resistant coating on the surface of the embedded memory chip, thereby realizing the corrosion resistance enhancement of the memory chip without affecting the electrical property of the memory chip.
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.
Example 1
Preparation of a dioxy-terminated siloxane having the molecular structure of formula (1)
Uniformly mixing 1 equivalent of tetramethyl dihydrosiloxane and a platinum catalyst, heating to a reaction temperature of 55-66 ℃, slowly dropwise adding 2-2.3 equivalent of allyl alcohol glycidyl ether under stirring, keeping the temperature, stirring for reaction for 8-30 hours, stopping the reaction, filtering and recovering the catalyst, and performing rotary evaporation to obtain the dicyclo-terminated siloxane with the molecular structure of formula (1), wherein the platinum catalyst is a commercially available supported platinum catalyst, the platinum catalyst is not particularly limited, the adding amount of platinum is 3-5% of the mass of a reaction substrate, and the specific adding amount of the platinum catalyst is converted and added according to the loading amount of the commercially available platinum catalyst;
the reaction temperature in the above examples was 55 ℃, 56 ℃, 57 ℃, 58 ℃, 59 ℃, 60 ℃, 61 ℃, 62 ℃, 63 ℃, 64 ℃, 65 ℃ or 66 ℃;
The reaction time in the above examples was 8h, 9h, 10h, 11h, 12h, 13h, 14h, 15h, 16h, 17h, 18h, 19h, 20h, 21h, 22h, 23h, 24h, 25h, 26h, 27h, 28h, 29h, or 30h;
the tetramethyl dihydro siloxane and allyl alcohol glycidyl ether in the above examples are all commercially available, and the present invention is not particularly limited herein.
Example 2
Preparation of triols having the molecular structure of formula (2)
Uniformly mixing 1 equivalent of [3- (trimethoxysilyl) propyl ] succinic anhydride and ethanol, heating to a reaction temperature of 60-70 ℃, slowly dropwise adding 1-1.3 equivalent of tris (hydroxymethyl) aminomethane under stirring, keeping the temperature, stirring for reaction for 3-24 hours, stopping the reaction, and performing rotary evaporation to obtain the triol with the molecular structure of formula (2), wherein the ethanol is dissolved [3- (trimethoxysilyl) propyl ] succinic anhydride and tris (hydroxymethyl) aminomethane, and the addition amount can be such that the [3- (trimethoxysilyl) propyl ] succinic anhydride and tris (hydroxymethyl) aminomethane are completely dissolved, which is a common knowledge in the technical field, and the invention is not limited by the fact that in the embodiment of the invention, the addition mass of the ethanol is 0.8-1.5 times of the total mass of the [3- (trimethoxysilyl) propyl ] succinic anhydride and tris (hydroxymethyl) aminomethane;
the reaction temperature in the above examples was 60 ℃, 61 ℃, 62 ℃, 63 ℃, 64 ℃, 65 ℃, 66 ℃, 67 ℃, 68 ℃, 69 ℃ or 70 ℃;
the reaction time in the above examples was 3h, 4h, 5h, 6h, 7h, 8h, 9h, 10h, 11h, 12h, 13h, 14h, 15h, 16h, 17h, 18h, 19h, 20h, 21h, 22h, 23h or 24h;
the [3- (trimethoxysilyl) propyl ] succinic anhydride, the tris and ethanol in the above examples are commercially available, and the present invention is not particularly limited herein.
Example 3
Preparation of binding resin
Uniformly mixing 3-4 equivalents of the double epoxy-terminated siloxane prepared in the embodiment 1 with tetrahydrofuran, adding sodium hydroxide, adjusting the pH of a reaction system to 10-11, heating to 50-65 ℃, slowly dropwise adding tetrahydrofuran containing 2 equivalents of the triol prepared in the embodiment 2 under stirring, carrying out heat preservation and stirring reaction for 4-24 hours, stopping the reaction, steaming, washing and drying to obtain bonding resin, wherein the tetrahydrofuran is prepared by dissolving the double epoxy-terminated siloxane and the triol, and the adding amount can be used for completely dissolving the double epoxy-terminated siloxane and the triol, which is common knowledge in the technical field, and the invention is not limited by the common knowledge;
The reaction temperature in the above examples was 50 ℃, 51 ℃, 52 ℃, 53 ℃, 54 ℃, 55 ℃, 56 ℃, 57 ℃, 58 ℃, 59 ℃, 60 ℃, 61 ℃, 62 ℃, 63 ℃, 64 ℃, or 65 ℃;
The reaction time in the above examples was 4h, 5h, 6h, 7h, 8h, 9h, 10h, 11h, 12h, 13h, 14h, 15h, 16h, 17h, 18h, 19h, 20h, 21h, 22h, 23h or 24h.
Example 4
A radioresistant processing method of an embedded memory chip in a space environment satellite comprises the following steps:
Firstly, preparing raw materials of a radiation-resistant coating according to the percentage by mass of Table 1, wherein the binding resin is prepared in the example 3, and barium sulfate, rui Qin powder and a curing agent are all commercially available;
Secondly, mixing and grinding barium sulfate, binding resin and Rui Qin powdery mildew to obtain powder, adding a curing agent into the powder, spraying the powder on the surface of the chip obtained by the surface treatment, and curing to obtain an anti-radiation coating;
wherein, the particle size of the powder obtained in the second step and the thickness of the anti-radiation coating on the surface of the finally obtained anti-radiation embedded memory chip are shown in Table 2 in detail.
Table 1 (mass percent)
Recipe number Barium sulfate Binding resin Rui Qin powdery mildew Curing agent
1 35% 45% 19% 1%
2 40% 40% 18.5% 1.5%
3 50% 30% 19.5% 0.5%
4 39% 38% 25% 1%
5 50.5% 38% 20% 1.5%
6 49.5% 35% 15% 0.5%
7 35% 40% 24% 1%
8 38.5% 35% 25% 1.5%
9 44.5% 30% 25% 0.5%
The resulting radiation-protected embedded memory chips of example 4 are labeled as examples 4-1, 4-2, 4-3, 4-4, 4-5, 4-6, 4-7, 4-8 and 4-9.
Performance test:
The radiation-resistant embedded memory chip obtained in the embodiment 4 is subjected to a temperature change test and check test at-55 ℃ to 125 ℃, and specific test conditions are as follows: placing the anti-radiation embedded memory chip into a low-temperature refrigerator or oven with set temperature for heat preservation and fixing time, taking out, observing the appearance of the memory chip, examining the hot start and cold start performance of the memory chip, and observing the internal line of the memory chip through X rays;
Wherein the set temperature is-55+/-2 ℃, 40+/-2 ℃, 20+/-2 ℃, 0+/-2 ℃, 60+/-2 ℃, 85+/-2 ℃, 95+/-2 ℃, 105+/-2 ℃ and 125+/-2 ℃ and the fixing time is 3 hours, 8 hours, 12 hours, 24 hours, 48 hours and 72 hours;
the results showed that the surfaces of the embedded memory chips subjected to the radioresistance treatment of example 4-1, example 4-2, example 4-3, example 4-4, example 4-5, example 4-6, example 4-7, example 4-8 and example 4-9 were free from swelling and cracking, the internal lines were free from cracking, and the hot-start and cold-start performances of the memory chips were not affected.
The anti-radiation embedded memory chip obtained in example 4 and the embedded memory chip not subjected to the anti-radiation treatment (as a blank test group) were subjected to an anti-cumulative radiation performance test together, and the results are shown in table 2.
TABLE 2
Thickness of the radiation-resistant coating Cumulative radiation resistance
Example 4-1 5μm 3.2×105rad(Si)
Example 4-2 5μm 3.1×105rad(Si)
Examples 4 to 3 5μm 3.0×105rad(Si)
Examples 4 to 4 10μm 3.6×105rad(Si)
Examples 4 to 5 10μm 3.5×105rad(Si)
Examples 4 to 6 10μm 3.4×105rad(Si)
Examples 4 to 7 15μm 3.9×105rad(Si)
Examples 4 to 8 15μm 3.8×105rad(Si)
Examples 4 to 9 15μm 3.8×105rad(Si)
Blank test group / 1000rad(Si)
From the data in Table 1, it can be seen that the radiation dose versus blank test comparison of the inventive examples increased by almost two orders of magnitude without affecting the other electrical properties of the IC.
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.

Claims (7)

1. A radioresistant processing method of an embedded memory chip in a space environment satellite is characterized by comprising the following steps:
the anti-radiation coating comprises the following raw materials in percentage by weight: 35-55% of barium sulfate, 20-45% of binding resin, 15-25% of Qin powdery mildew and 0.4-1.5% of curing agent;
mixing and grinding barium sulfate, binding resin and Ruiki powder to obtain powder, adding a curing agent into the powder, spraying the powder on the surface of a chip obtained by surface treatment, and curing to obtain a radiation-resistant coating;
The bonding resin is formed by hyperbranched reaction of dioxy-terminated siloxane and triol under alkaline conditions;
the molecular structural formula of the dioxy terminated siloxane is shown as follows:
the molecular structural formula of the triol is shown as follows:
The molar ratio of the dioxy terminated siloxane to the triol is 3-4:2;
the reaction temperature of the hyperbranched reaction is 50-65 ℃ and the reaction time is 4-24 hours;
The thickness of the radiation-resistant coating is 5-15 mu m.
2. The method for radiation-resistant processing of an embedded memory chip in a space environment satellite according to claim 1, wherein the solvent used in the hyperbranched reaction is one of organic ether solvents.
3. The method for radiation-resistant treatment of an embedded memory chip in a space environment satellite according to claim 1, wherein the dioxy-terminated siloxane is formed by hydrosilylation reaction of tetramethyl dihydro siloxane and allyl alcohol glycidyl ether under the catalysis of a platinum catalyst.
4. The method for radiation-resistant treatment of an embedded memory chip in a space environment satellite according to claim 3, wherein the molar ratio of the tetramethyl dihydro siloxane to the allyl alcohol glycidyl ether is 1:2-2.3.
5. The method for radiation-resistant treatment of an embedded memory chip in a space environment satellite according to claim 3, wherein the hydrosilylation reaction temperature is 55-66 ℃ and the reaction time is 8-30h.
6. The method for radiation-resistant treatment of an embedded memory chip in a space environment satellite according to claim 1, wherein the triol is formed by reacting [3- (trimethoxysilyl) propyl ] succinic anhydride and tris-hydroxymethyl aminomethane in a first solvent through amino and anhydride.
7. The method for radiation-resistant treatment of an embedded memory chip in a space environment satellite according to claim 6, wherein the molar ratio of the triol to the [3- (trimethoxysilyl) propyl ] succinic anhydride to the tris is 1:1-1.3, wherein the first solvent is ethanol, and the reaction temperature of the triol is 60-70 ℃ and the reaction time is 3-24h, wherein the reaction temperature of the triol is [3- (trimethoxysilyl) propyl ] succinic anhydride and the reaction time of the trimethylol aminomethane.
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