CN106494107A - A kind of laser index carving method for microelectronic package - Google Patents

Abstract

The invention relates to a laser marking method for microelectronic packaging shells, which includes the following steps: 1) editing and storing the laser marking content with AutoCAD or the equipment's own software; 2) according to the type of substrate Select the appropriate laser to complete the preparation of start-up, equipment calibration, fixtures and consumables; 3) Set the process parameters; 4) Use the laser emitted by the laser to cut out the content edited in step 1) on the substrate; 5) Plating Form the intermediate coating; 7) Assemble the base material to form the shell; 8) Plating the shell coating on the shell to form a finished product; 9) Conduct performance index testing of the finished product. Beneficial effects of the present invention: 1) The graphics, characters, and barcodes marked by laser are clear and never fall off, meeting the evaluation requirements of air tightness of the shell, salt spray resistance and other indicators; 2) Non-contact automatic processing, with flexible operation , fast speed, no wear and other advantages.

Description

A laser marking method for microelectronic packaging shell

technical field

The invention relates to a laser marking method for a microelectronic packaging shell, belonging to the technical field of microelectronic manufacturing.

Background technique

With the development of communication, aerospace, automobile and consumer electronics industries and the improvement of automation level, the requirements for the size, function and stability of electronic circuits and devices used are getting higher and higher; partial circuit disconnection of finished products, unique identification, etc. It is an important method to realize local functions, information collection, tracking and management; traditional methods such as screen printing and printing are suitable for products with good consistency and the same template, low process flexibility, continuous numbering, and subsequent processing and use. Easy to fall off; laser cutting is a processing method that uses high-energy-density laser beams to act on the target to cause physical or chemical changes on the target surface to obtain design patterns. It has clear graphics, characters and barcodes, and will never fall off; Processing, flexible operation, fast speed, no wear and other characteristics, but due to the characteristics of the substrate itself, the absorption of the substrate to the laser, and the conditions of subsequent processing, the depth of the cut marks formed by the laser on the material is different, resulting in product appearance, Airtightness, insulation resistance, salt spray, mechanical shock and other performance degradation.

Materials such as beryllium oxide, AlN, Cu, Mo, W, steel, Kovar alloy, and Cu/W and Cu/Mo are similar to chips due to their thermal expansion coefficients; excellent thermal conductivity; stable chemical properties, very good electrical properties; good EMI/RFI shielding ability; thermal expansion coefficient similar to chip, low density, sufficient strength and hardness; good processing or forming performance; excellent plating, solderability and corrosion resistance, often used to support chips , electrical connection, heat absorption and divergence; with the development of industries such as communications, aerospace, automobiles and consumer electronics and the improvement of automation levels, the functions, dimensions, airtightness, insulation resistance, salt spray of electronic circuits and devices used Stability requirements such as mechanical shock and mechanical shock are getting higher and higher. Partial circuit disconnection of finished products and unique identification are important methods to realize partial functions, information collection, tracking and management.

Laser cutting is under the control of the computer, the pulsed laser beam with a certain power and frequency is output through the discharge of the pulsed laser, and the pulsed laser beam is focused on the surface of the processed substrate through optical transmission, reflection and focusing lens group to form a fine , high energy density spot, the focal spot near the surface of the material to be processed produces instantaneous high-temperature melting, vaporization and strong airflow to form pits on the surface of the material. Under the precise control of the computer, the laser beam and the material to be processed follow the preset route, Speed, delay, etc. are carried out relative movement, so as to obtain the designed graphics, characters, barcodes, etc., and process them into microelectronic packaging shells with certain functions and uses through intermediate layer plating, assembly, welding, and plating processes as required.

Contents of the invention

What the present invention proposes is a kind of laser marking method used for microelectronic packaging casing, select the laser with suitable type, output power and central wavelength according to the size characteristics of the substrate and the absorption characteristics of the laser, firstly design the graphics, characters and Edit the bar code, etc., and then use the appropriate processing parameters, through cutting, intermediate layer plating, assembly, welding and plating, etc., the purpose is to make the product appearance and air tightness, insulation resistance, salt spray, mechanical Performance such as impact has been greatly improved.

Technical solution of the present invention: what the present invention proposes is a kind of laser marking method that is used for the microelectronic packaging casing, and this method comprises the following steps:

1) Use AutoCAD or the software that comes with the device to edit and store the laser-marked content;

2) Select the appropriate laser according to the type of substrate, and complete the preparation of start-up, equipment calibration, fixtures and consumables;

3) Set process parameters;

4) Cut out the content edited in step 1) on the substrate with the laser emitted by the laser;

5) Plating to form a protective intermediate coating;

7) Assemble the substrate to form a shell;

8) Coating a functional coating on the shell to form a finished product;

9) Conduct performance index testing of finished products.

Beneficial effects of the present invention:

1) Fiber lasers, semiconductor lasers or _CO2 lasers with an output power of 0.5W to 1000W and a center wavelength of 100nm to 2μm are used in beryllium oxide, aluminum nitride, copper, molybdenum, tungsten, steel, Kovar alloy, copper-tungsten alloy , copper-molybdenum alloy, ceramics and other substrates are cut out of graphics, characters and barcodes with a depth of 0.1 to 200 μm, and are plated to form an intermediate coating layer, assembled, welded and shell coated, so that the laser-marked graphics, The characters and barcodes are clear and never fall off, and the performance indicators meet the requirements of the shell assessment;

2) The present invention is a non-contact automatic processing, which has the advantages of flexible operation, high speed, and no wear.

detailed description

A laser marking method for microelectronic packaging housing, the method may further comprise the steps:

1) Use AutoCAD or the software that comes with the device to edit and store the laser-marked content;

2) Select the appropriate laser according to the type of substrate, and complete the preparation of start-up, equipment calibration, fixtures and consumables;

3) Set process parameters;

4) Cut out the content edited in step 1) on the substrate with the laser emitted by the laser;

5) Plating to form a protective intermediate coating;

7) Assemble the base material to form a shell; the conventional brazing process can be used for welding during assembly;

8) Coating a functional coating on the shell to form a finished product;

9) Conduct performance index testing of finished products.

The content of the laser marking is graphics and/or characters and/or barcodes.

The base material is one of beryllium oxide, aluminum nitride, copper, molybdenum, tungsten, steel, Kovar alloy, copper-tungsten alloy, copper-molybdenum alloy and ceramics.

Described laser is a kind of in fiber laser, semiconductor laser, CO ₂ laser;

The output power of the laser is 0.5 W to 1000 W, and the central wavelength of the laser emitted by the laser is 100 nm to 2 μm; the process parameters include rated output power, number of cutting circles, cutting speed, and time delay; wherein the rated output power is 0.5 W～1000W, the number of cutting circles is 1～100, the cutting speed is 10 mm～1000mm/s, and the time delay is 10～1000μs.

The depth of the graphics and/or characters and/or barcodes on the finished product is 0.1 μm˜100 μm.

The intermediate protective coating is one of silver layer, copper layer, tin layer, nickel layer, chromium layer and gold layer, and the thickness of the coating is 0.1 μm to 20 μm; the functional coating of the shell is silver layer, copper layer, One of the tin layer, nickel layer, chromium layer, and gold layer, the thickness of the coating is 0.1 μm to 20 μm; through the coating, the marked graphics, characters, and barcodes are clear and will not fall off permanently, meeting the airtightness of the shell and salt resistance Fog performance and other indicators assessment requirements.

According to the type of base material, the appropriate laser is selected, specifically carbon dioxide laser, UV laser can be used to cut beryllium oxide, aluminum nitride, alumina ceramics, etc.; Nd:YAG laser, UV laser can be used to cut copper, molybdenum, tungsten, steel , Kovar alloy, copper-tungsten alloy, copper-molybdenum alloy.

The intermediate coating plays protective, functional and decorative roles.

Example 1

A laser marking method for a microelectronic package housing, the method comprising the steps of:

a) Use AutoCAD to edit graphics and characters, using Song typeface, and the character height is 2.0mm;

b) Choose UV laser or carbon dioxide laser to cut beryllium oxide, aluminum nitride, alumina ceramics, etc., the rated output power of the laser is 10W, and the central wavelength of the laser emitted by the laser is 355nm, 10.6um; complete the start-up, workbench, camera and focal length Calibration, selection of suitable fixtures and consumables preparation;

c) Process parameter setting, output power 5 W, number of cutting circles 2, speed 120mm/s, delay 500μs;

d) Cut the designed graphics, characters and barcodes on the substrate with laser and complete the necessary index detection;

e) Nickel plating on the substrate with a thickness of 2 μm;

f) Assemble the parts and weld them with a conventional brazing process;

g) Protective, functional and decorative gold plating, with a thickness of 2 μm;

h) Testing of performance indicators of finished products.

Example 2

A laser marking method for a microelectronic package housing, the method comprising the steps of:

a) Use the software that comes with the device to edit graphics and characters, using Song typeface, and the character height is 2.0mm;

b) Choose UV laser, Nd:YAG laser cutting copper, molybdenum, tungsten, steel, Kovar, copper-tungsten alloy, copper-molybdenum alloy, etc., the rated output power of the laser is 20 W, and the center wavelength of the laser emitted by the laser is 355nm. 1064nm; complete booting, calibration of workbench, camera and focal length, selection of suitable fixtures and consumables;

c) Process parameter setting, output power 12 W, number of cutting circles 5, speed 300mm/s, delay 500μs;

d) Cut the designed graphics, characters and barcodes on the substrate with laser and complete the necessary index detection;

e) Nickel plating on the substrate with a thickness of 5 μm;

f) Assemble the parts and weld them with a conventional brazing process;

g) Protective, functional and decorative gold plating, with a thickness of 10 μm;

h) Testing of performance indicators of finished products.

Example 3

A laser marking method for a microelectronic package housing, the method comprising the steps of:

a) Use AutoCAD to edit graphics and characters, using Song typeface, and the character height is 2.0mm;

b) Choose a UV laser to cut beryllium oxide, aluminum nitride, and alumina ceramics. The rated output power of the laser is 10W, and the center wavelength of the laser emitted by the laser is 355nm, 10.6um. Preparation of fixtures and consumables;

c) Process parameter setting, output power 5 W, number of cutting circles 2, speed 120mm/s, delay 500μs;

d) Cut the designed graphics, characters and barcodes on the substrate with laser and complete the necessary index detection;

e) Nickel plating on the substrate with a thickness of 2 μm;

f) Assemble the parts and weld them with a conventional brazing process;

g) Protective, functional and decorative gold plating, with a thickness of 2 μm;

h) Testing of performance indicators of finished products.

Example 4

A laser marking method for a microelectronic package housing, the method comprising the steps of:

a) Use AutoCAD to edit graphics and characters, using Song typeface, and the character height is 2.0mm;

b) Choose a carbon dioxide laser to cut beryllium oxide, aluminum nitride, and alumina ceramics. The rated output power of the laser is 10W, and the center wavelength of the laser emitted by the laser is 355nm, 10.6um. Preparation of fixtures and consumables;

c) Process parameter setting, output power 5 W, number of cutting circles 2, speed 120mm/s, delay 500μs;

d) Cut the designed graphics, characters and barcodes on the substrate with laser and complete the necessary index detection;

e) Nickel plating on the substrate with a thickness of 2 μm;

f) Assemble the parts and weld them with a conventional brazing process;

g) Protective, functional and decorative gold plating, with a thickness of 2 μm;

h) Testing of performance indicators of finished products.

Example 5

A laser marking method for a microelectronic package housing, the method comprising the steps of:

a) Use the software that comes with the device to edit graphics and characters, using Song typeface, and the character height is 2.0mm;

b) Choose UV laser to cut copper, molybdenum, tungsten, steel, Kovar alloy, copper-tungsten alloy, copper-molybdenum alloy, the rated output power of the laser is 20 W, and the center wavelength of the laser emitted by the laser is 355nm, 1064nm; complete the start-up and work Stage, camera and focal length calibration, selection of suitable fixtures and consumables preparation;

c) Process parameter setting, output power 12 W, number of cutting circles 5, speed 300mm/s, delay 500μs;

d) Cut the designed graphics, characters and barcodes on the substrate with laser and complete the necessary index detection;

e) Nickel plating on the substrate with a thickness of 5 μm;

f) Assemble the parts and weld them with a conventional brazing process;

g) Protective, functional and decorative gold plating, with a thickness of 10 μm;

h) Testing of performance indicators of finished products.

Example 6

A laser marking method for a microelectronic package housing, the method comprising the steps of:

a) Use the software that comes with the device to edit graphics and characters, using Song typeface, and the character height is 2.0mm;

b) Choose Nd:YAG laser to cut copper, molybdenum, tungsten, steel, Kovar alloy, copper-tungsten alloy, copper-molybdenum alloy, the rated output power of the laser is 20 W, and the center wavelength of the laser emitted by the laser is 355nm, 1064nm; complete the start-up , workbench, camera and focal length calibration, selection of suitable fixtures and consumables preparation;

c) Process parameter setting, output power 12 W, number of cutting circles 5, speed 300mm/s, delay 500μs;

d) Cut the designed graphics, characters and barcodes on the substrate with laser and complete the necessary index detection;

e) Nickel plating on the substrate with a thickness of 5 μm;

f) Assemble the parts and weld them with a conventional brazing process;

g) Protective, functional and decorative gold plating, with a thickness of 10 μm;

h) Testing of performance indicators of finished products.

Claims (7)

1. a kind of laser marking method that is used for microelectronic packaging shell, is characterized in that comprising the steps: 1) Use AutoCAD or the software that comes with the device to edit and store the laser-marked content; 2) Select the appropriate laser according to the type of substrate, and complete the preparation of start-up, equipment calibration, fixtures and consumables; 3) Set process parameters; 4) Cut out the content edited in step 1) on the substrate with the laser emitted by the laser; 5) Plating forms an intermediate protective coating; 7) Assemble the base material to form a shell; 8) Coating a functional coating on the shell to form a finished product; 9) Carry out performance index testing of finished products. 2. A laser marking method for a microelectronic package housing according to claim 1, wherein the content of the laser marking is graphics and/or characters and/or barcodes. 3. A kind of laser marking method that is used for microelectronic package shell according to claim 1, it is characterized in that described base material can be beryllium oxide, aluminum nitride, copper, molybdenum, tungsten, steel, Kovar One of alloys, copper-tungsten alloys, copper-molybdenum alloys, and ceramics. 4. a kind of laser marking method that is used for microelectronic packaging shell according to claim 1 is characterized in that described laser device is a kind of in fiber laser device, semiconductor laser device, _CO2 laser device; The output of described laser device The power ranges from 0.5 W to 1000 W, and the center wavelength of the laser light emitted by the laser ranges from 100 nm to 2 μm. 5. A kind of laser marking method that is used for microelectronic package shell according to claim 1, it is characterized in that The process parameters described include rated output power, number of cutting circles, cutting speed, and time delay; wherein the rated output power is 0.5 W-1000 W, the number of cutting circles is 1-100, the cutting speed is 10 mm-1000 mm/s, and the time delay is 10 ~ 1000μs. 6 . A laser marking method for microelectronic packaging shells according to claim 1 , characterized in that the depth of the graphics and/or characters and/or barcodes on the finished product is 0.1 μm to 100 μm. 7. A kind of laser marking method that is used for microelectronics packaging shell according to claim 1, it is characterized in that described intermediate protective coating is silver layer, copper layer, tin layer, nickel layer, chromium layer, gold layer One of them, the thickness of the coating is 0.1 μm to 20 μm, and the functional coating is one of silver layer, copper layer, tin layer, nickel layer, chromium layer and gold layer, and the thickness of the coating is 0.1 μm to 20 μm.