CN110993556A - Method for preparing ceramic thin film circuit with electroplated nickel layer as mask layer - Google Patents
Method for preparing ceramic thin film circuit with electroplated nickel layer as mask layer Download PDFInfo
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- CN110993556A CN110993556A CN201911144691.1A CN201911144691A CN110993556A CN 110993556 A CN110993556 A CN 110993556A CN 201911144691 A CN201911144691 A CN 201911144691A CN 110993556 A CN110993556 A CN 110993556A
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- H—ELECTRICITY
- H01—ELECTRIC ELEMENTS
- H01L—SEMICONDUCTOR DEVICES NOT COVERED BY CLASS H10
- H01L21/00—Processes or apparatus adapted for the manufacture or treatment of semiconductor or solid state devices or of parts thereof
- H01L21/70—Manufacture or treatment of devices consisting of a plurality of solid state components formed in or on a common substrate or of parts thereof; Manufacture of integrated circuit devices or of parts thereof
- H01L21/702—Manufacture or treatment of devices consisting of a plurality of solid state components formed in or on a common substrate or of parts thereof; Manufacture of integrated circuit devices or of parts thereof of thick-or thin-film circuits or parts thereof
- H01L21/707—Manufacture or treatment of devices consisting of a plurality of solid state components formed in or on a common substrate or of parts thereof; Manufacture of integrated circuit devices or of parts thereof of thick-or thin-film circuits or parts thereof of thin-film circuits or parts thereof
Abstract
The invention discloses a method for preparing a ceramic thin film circuit with an electroplated nickel layer as a mask layer. The invention can omit the step of secondary photoetching by using the nickel plating layer as the mask layer, thereby simplifying the process, improving the production efficiency, avoiding the error caused by manual alignment during the secondary photoetching and improving the precision of the product; meanwhile, the using amount of materials such as photoresist and the like is reduced, the production cost is reduced, and the harm to the environment and production personnel caused by using the materials such as photoresist and the like is effectively reduced; in addition, the invention does not need expensive equipment of dry etching, and has the characteristics of simple process flow, small equipment quantity, industrialization, low cost and large-scale production and the like.
Description
Technical Field
The invention belongs to the technical field of semiconductor manufacturing, and particularly relates to a method for preparing a ceramic thin film circuit with an electroplated nickel layer as a mask layer.
Background
The thin film circuit has the characteristics of small volume, light weight, high reliability, high wiring density and capability of integrating passive elements, so that the thin film circuit is widely applied to microwave circuits in the fields of airborne, satellite-borne, aerospace and the like.
The traditional thin film circuit production process mainly comprises two processes, wherein the first process comprises the following steps: cleaning a ceramic wafer, sputtering, photoetching, electroplating, secondary photoetching and wet etching Au/TiW; the second method is as follows: cleaning the ceramic wafer, sputtering, photoetching, electroplating, secondary photoetching, dry etching Au, and wet etching TiW. The two technological processes comprise two photoetching processes, the process is complex, the cost is high, and the situation of manual alignment error exists in the secondary photoetching process, so that the improvement of the product precision is not facilitated; and the equipment needed when dry etching is utilized is expensive, and the equipment investment in the early stage and the equipment maintenance cost in the later stage are high.
Disclosure of Invention
The invention aims to provide a method for preparing a ceramic thin film circuit by taking an electroplated nickel layer as a mask layer.
The technical solution for realizing the purpose of the invention is as follows: a method for preparing a ceramic thin film circuit with an electroplated nickel layer as a mask layer comprises the following steps:
step 1, cleaning a ceramic wafer;
step 2, sputtering Au/TiW bottom metal;
step 3, photoetching
1) Pre-baking: putting the wafer rack with the ceramic substrates into an oven for baking, taking out the wafer rack after prebaking is finished, and putting the wafer rack into a wafer box;
2) gluing: putting the ceramic substrate into a glue spreader for spreading glue, and putting a wafer frame into a wafer box after spreading the glue;
3) exposure: taking a film circuit mask, adjusting relevant exposure parameters, and putting a wafer into a machine for exposure;
4) and (3) developing: placing the exposed film in a film frame with the right side facing upwards; developing in a manual mode, and drying after washing;
5) hardening the film: putting the developed wafer into an oven for hardening;
step 4, electroplating a gold layer, namely electroplating a nickel layer as a mask layer on the basis of the gold layer;
and 5, etching the Au/TiW layer by a wet method, and etching the nickel layer by the wet method to prepare the required thin film circuit.
Further, in the step 4, a gold layer of 3-4 micrometers is electroplated, and a nickel layer of 1 micrometer is electroplated on the basis of the gold layer to serve as a mask layer.
Furthermore, the temperature of the gold plating layer is 55-60 ℃, and the current density is 0.1-0.6A/dm2。
Further, the temperature of the nickel electroplating layer is 50-60 ℃, and the current density is 0.3-3A/dm2。
Further, the step 1 of cleaning the ceramic wafer specifically comprises the following steps.
(1) Preparing a cleaning solution:
in the cleaning solution 1, concentrated sulfuric acid: hydrogen peroxide is 3: 1
In cleaning solution 2, concentrated hydrochloric acid: hydrogen peroxide: water 1: 2: 5
(2) A cleaning step:
heating the cleaning solution 1 to 120 ℃, and placing the ceramic wafer in the cleaning solution for cleaning for 15 min;
after the cleaning is finished, taking out the ceramic wafer and washing the ceramic wafer by using a large amount of pure water, simultaneously heating the cleaning solution 2 to 70 ℃, then placing the ceramic wafer in the cleaning solution for cleaning for 15min, and washing the ceramic wafer by using the pure water after the cleaning is finished; and after the washing, putting the ceramic wafer into a drying machine for drying for later use.
Further, the thickness of TiW is
Au thickness of
Further, the pre-baking process comprises the following steps: and (3) placing the wafer rack with the ceramic substrate into an oven for baking at the baking temperature of 90 +/-5 ℃ for 30 +/-5 min, and taking out the wafer rack after the pre-baking is finished and placing the wafer rack into a wafer box.
Further, the coating speed is (2000 +/-100) rpm, and the exposure speed is 400 +/-30 mJ/cm2。
Further, the development is carried out in a manual mode, 1-2 pieces are carried out each time, and the development time is 20-30 s.
Further, the developed wafer is put into an oven for hardening, the baking temperature is (100 +/-5) DEG C, and the baking time is set to be (30 +/-5) min.
Compared with the prior art, the invention has the remarkable advantages that: (1) the invention simplifies the process flow, improves the production efficiency and the product stability; (2) the secondary photoetching process step is omitted, so that the use of materials such as photoresist, developing solution and the like is reduced, the production cost is reduced, and the harm of glue materials to the environment and the health of production personnel is reduced; (3) the process of manual alignment in the secondary photoetching process is cancelled, so that the influence of manual operation errors on the product precision is avoided, and the product quality of the thin film circuit is improved; (4) expensive equipment of dry etching is not needed, high cost caused by purchase and subsequent maintenance of the dry etching equipment is avoided, production material investment is reduced, and industrial and large-scale production is facilitated.
Detailed Description
A method for preparing a ceramic thin film circuit by using a nickel plating layer as a mask layer comprises the following steps:
step 1, cleaning the ceramic wafer
(1) Preparing a cleaning solution:
cleaning solution 1: (concentrated sulfuric acid: hydrogen peroxide ═ 3: 1)
Cleaning solution 2: (concentrated hydrochloric acid: hydrogen peroxide: water ═ 1: 2: 5)
The above proportions are volume ratios.
(2) A cleaning step:
heating the cleaning solution 1 to 120 ℃, and placing the ceramic wafer in the cleaning solution for cleaning for 15 min; after the end of the washing, the ceramic sheet was taken out and rinsed with a large amount of pure water, while the washing solution 2 was heated to 70 ℃, and then the ceramic sheet was left therein to be washed for 15min, and rinsed with a large amount of pure water after the end of the washing. And after the washing, putting the ceramic wafer into a drying machine for drying for later use.
And 2, sputtering Au/TiW bottom layer metal, wherein the surface layer is gold, and the bottom layer is TIW.
TiW
Au
Step 3, photoetching
(1) Prebaking
And (3) placing the substrate rack with the ceramic substrate into an oven for baking at the baking temperature of 90 +/-5 ℃ for 30 +/-5 min. And taking out the film frame and putting the film frame into a film box after the pre-drying is finished.
(2) Glue spreading
Putting the ceramic substrate into a gluing machine for gluing, wherein the conditions are as follows: the rotation speed is (2000 +/-100) rpm. And after the gluing is finished, putting the film frame into a film box.
(3) Exposure method
Taking the film circuit mask, adjusting the relevant exposure parameters, and placing the wafer into the machine for exposure at an exposure speed of 400 +/-30 mJ/cm2。
(4) Development
And placing the exposed film in a film frame with the right side facing upwards. And developing in a manual mode for 20-30s for 1-2 pieces each time. And (5) drying after washing.
(5) Hard coating
And putting the developed wafer into an oven for hardening. The baking temperature is 100 +/-5 ℃, and the baking time is set to be 30 +/-5 min.
Step 4, electroplating
(1) Electrogilding
Electroplating a 3-4 micron gold layer at 55-60 deg.C and current density of 0.1-0.6A/dm2。
(2) Electroplated nickel mask layer
Electroplating a nickel layer of about 1 micron as a mask layer on the basis of the gold-plated layer at the temperature of 50-60 ℃ and the current density of 0.3-3A/dm2。
Step 5, etching
(1) Etching Au/TiW by a wet method;
(2) and wet etching the nickel layer.
Thus, a desired thin film circuit can be prepared.
The invention provides a method for preparing a ceramic thin film circuit by using an electroplated nickel layer as a mask layer, aiming at replacing secondary photoetching by using the electroplated nickel layer as the mask layer, simplifying the process, improving the production efficiency, improving the product precision, reducing the production cost, and having the characteristics of simple preparation process, less required production equipment, industrialization, low cost and large-scale production and the like.
The present invention will be described in detail with reference to examples.
Example 1
The embodiment provides a method for preparing an alumina ceramic thin film circuit, which comprises the following steps:
step 1, Al2O3Ceramic wafer cleaning
(1) Preparing a cleaning solution:
cleaning solution 1: (concentrated sulfuric acid: hydrogen peroxide ═ 3: 1)
Cleaning solution 2: (concentrated hydrochloric acid: hydrogen peroxide: water ═ 1: 2: 5)
(2) A cleaning step:
heating the cleaning solution 1 to 120 ℃, and placing the ceramic wafer in the cleaning solution for cleaning for 15 min; after the end of the washing, the ceramic sheet was taken out and rinsed with a large amount of pure water, while the washing solution 2 was heated to 70 ℃, and then the ceramic sheet was left therein to be washed for 15min, and rinsed with a large amount of pure water after the end of the washing. And after the washing, putting the ceramic wafer into a drying machine for drying for later use.
Step 2, sputtering
Sputtering Au/TiW bottom metal.
TiW
Au
Step 3, photoetching
(1) Prebaking
And (3) placing the substrate rack with the ceramic substrate into an oven for baking at the baking temperature of 90 +/-5 ℃ for 30 +/-5 min. And taking out the film frame and putting the film frame into a film box after the pre-drying is finished.
(2) Glue spreading
Putting the ceramic substrate into a gluing machine for gluing, wherein the conditions are as follows: the rotation speed is (2000 +/-100) rpm. And after the gluing is finished, putting the film frame into a film box.
(3) Exposure method
Taking the film circuit mask, adjusting the relevant exposure parameters, and placing the wafer into the machine for exposure at an exposure speed of 400 +/-30 mJ/cm2。
(4) Development
And placing the exposed film in a film frame with the right side facing upwards. And developing in a manual mode for 20-30s for 1-2 pieces each time. And (5) drying after washing.
(5) Hard coating
And putting the developed wafer into an oven for hardening. Baking at 100 + -5 deg.C for 30 + -5 min
Step 4, electroplating
(1) Electrogilding
Electroplating 3 micron gold layer at 56 deg.C and current density of 0.3A/dm2。
(2) Electroplated nickel mask layer
Electroplating 1 micrometer nickel layer as mask layer on the gold-plated layer at 55 deg.C and current density of 1A/dm2。
Step 5, etching
(1) And etching Au/TiW by a wet method.
(2) And wet etching the nickel layer.
Example 2
This example prepares an aluminum nitride ceramic thin film circuit
Step 1, cleaning AlN ceramic plates
(1) Preparing a cleaning solution:
cleaning solution 1: (concentrated sulfuric acid: hydrogen peroxide ═ 3: 1)
Cleaning solution 2: (concentrated hydrochloric acid: hydrogen peroxide: water ═ 1: 2: 5)
(2) A cleaning step:
heating the cleaning solution 1 to 120 ℃, and placing the ceramic wafer in the cleaning solution for cleaning for 15 min; after the end of the washing, the ceramic sheet was taken out and rinsed with a large amount of pure water, while the washing solution 2 was heated to 70 ℃, and then the ceramic sheet was left therein to be washed for 15min, and rinsed with a large amount of pure water after the end of the washing. And after the washing, putting the ceramic wafer into a drying machine for drying for later use.
Step 2, sputtering
Sputtering Au/TiW bottom metal.
TiW
Au
Step 3, photoetching
(1) Prebaking
And (3) placing the substrate rack with the ceramic substrate into an oven for baking at the baking temperature of 90 +/-5 ℃ for 30 +/-5 min. And taking out the film frame and putting the film frame into a film box after the pre-drying is finished.
(2) Glue spreading
Putting the ceramic substrate into a gluing machine for gluing, wherein the conditions are as follows: the rotation speed is (2000 +/-100) rpm. And after the gluing is finished, putting the film frame into a film box.
(3) Exposure method
Taking the film circuit mask, adjusting the relevant exposure parameters, and placing the wafer into the machine for exposure at an exposure speed of 400 +/-30 mJ/cm2。
(4) Development
And placing the exposed film in a film frame with the right side facing upwards. And developing in a manual mode for 20-30s for 1-2 pieces each time. And (5) drying after washing.
(5) Hard coating
Putting the developed wafer into an oven for hardening, wherein the baking temperature is 100 +/-5 ℃, and the baking time is set to be 30 +/-5 min
Step 4, electroplating
(1) Electrogilding
Electroplating a 4-micron gold layer at 55-60 deg.C and current density of 0.1-0.6A/dm2。
(2) Electroplated nickel mask layer
Electroplating a 1-micron nickel layer as a mask layer on the basis of the gold-plated layer at the temperature of 50-60 ℃ and the current density of 0.3-3A/dm2。
Step 5, etching
(1) Etching Au/TiW by a wet method;
(2) and wet etching the nickel layer.
Claims (10)
1. A method for preparing a ceramic thin film circuit with an electroplated nickel layer as a mask layer is characterized by comprising the following steps:
step 1, cleaning a ceramic wafer;
step 2, sputtering Au/TiW bottom metal;
step 3, photoetching
1) Pre-baking: putting the wafer rack with the ceramic substrates into an oven for baking, taking out the wafer rack after prebaking is finished, and putting the wafer rack into a wafer box;
2) gluing: putting the ceramic substrate into a glue spreader for spreading glue, and putting a wafer frame into a wafer box after spreading the glue;
3) exposure: taking a film circuit mask, adjusting relevant exposure parameters, and putting a wafer into a machine for exposure;
4) and (3) developing: placing the exposed film in a film frame with the right side facing upwards; developing in a manual mode, and drying after washing;
5) hardening the film: putting the developed wafer into an oven for hardening;
step 4, electroplating a gold layer, namely electroplating a nickel layer as a mask layer on the basis of the gold layer;
and 5, etching the Au/TiW layer by a wet method, and etching the nickel layer by the wet method to prepare the required thin film circuit.
2. The method for preparing a ceramic thin film circuit with an electroplated nickel layer as a mask layer according to claim 1, wherein a gold layer of 3-4 microns is electroplated, and a nickel layer of 1 micron is electroplated as a mask layer on the basis of the gold layer.
3. The method for producing a ceramic thin film circuit having an electroplated nickel layer as a mask layer according to claim 1 or 2, wherein the temperature of the electroplated gold layer is 55 to 60 ℃ and the current density is 0.1 to 0.6A/dm2。
4. According to claim 1 or 2The preparation method of the ceramic thin film circuit with the electroplated nickel layer as the mask layer is characterized in that the temperature of the electroplated nickel layer is 50-60 ℃, and the current density is 0.3-3A/dm2。
5. The method for preparing the ceramic thin film circuit with the electroplated nickel layer as the mask layer according to claim 1, wherein the step 1 of cleaning the ceramic sheet comprises the following specific steps:
(1) preparing a cleaning solution:
in the cleaning solution 1, concentrated sulfuric acid: hydrogen peroxide is 3: 1
In cleaning solution 2, concentrated hydrochloric acid: hydrogen peroxide: water 1: 2: 5
(2) A cleaning step:
heating the cleaning solution 1 to 120 ℃, and placing the ceramic wafer in the cleaning solution for cleaning for 15 min;
after the cleaning is finished, taking out the ceramic wafer and washing the ceramic wafer by using a large amount of pure water, simultaneously heating the cleaning solution 2 to 70 ℃, then placing the ceramic wafer in the cleaning solution for cleaning for 15min, and washing the ceramic wafer by using the pure water after the cleaning is finished; and after the washing, putting the ceramic wafer into a drying machine for drying for later use.
6. The method for preparing a ceramic thin film circuit having an electroplated nickel layer as a mask layer according to claim 1, wherein the thickness of TiW is
Au thickness of
7. The method for preparing a ceramic thin film circuit with an electroplated nickel layer as a mask layer according to claim 1, wherein the pre-baking process comprises the following steps: and (3) placing the wafer rack with the ceramic substrates into an oven for baking at the baking temperature of 85-95 ℃ for 25-35 min, taking out the wafer rack after pre-baking is finished, and placing the wafer rack into a wafer box.
8. The electroplated nickel of claim 1The preparation method of ceramic thin film circuit with layer as mask layer is characterized by that the coating rotation speed is 2000 +/-100 rpm, and the exposure speed is 400 +/-30 mJ/cm2。
9. The method for preparing a ceramic thin film circuit with an electroplated nickel layer as a mask layer according to claim 1, wherein the development is carried out in a manual mode for 1-2 sheets at a time, and the development time is 20-30 s.
10. The method for preparing a ceramic thin film circuit having electroplated nickel layer as mask layer according to claim 1, wherein the developed wafer is placed in an oven for hard coating at a baking temperature of (100 ± 5) ° c for a baking time of (30 ± 5) min.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN112234023A (en) * | 2020-12-16 | 2021-01-15 | 中国电子科技集团公司第九研究所 | Method for improving adhesion of metal film circuit on silicon wafer |
| CN114447552A (en) * | 2022-02-10 | 2022-05-06 | 西南应用磁学研究所(中国电子科技集团公司第九研究所) | Novel micro-strip circulator based on MEMS (micro-electromechanical systems) process and processing method thereof |
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| CN106298626A (en) * | 2016-08-11 | 2017-01-04 | 中国电子科技集团公司第四十研究所 | A kind of graphic plating method for microstrip circuit |
| CN106357231A (en) * | 2016-08-31 | 2017-01-25 | 安徽华东光电技术研究所 | Manufacturing method of thin-film microstrip filter |
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| CN103606520A (en) * | 2013-11-25 | 2014-02-26 | 中国电子科技集团公司第四十一研究所 | Method for manufacturing metal protective film used for film circuit test |
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| CN114447552A (en) * | 2022-02-10 | 2022-05-06 | 西南应用磁学研究所(中国电子科技集团公司第九研究所) | Novel micro-strip circulator based on MEMS (micro-electromechanical systems) process and processing method thereof |
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