KR20220029465A - Cutting method by using particle beam of metallic glass - Google Patents

Abstract

The present invention relates to a cutting method in which a particle beam of metallic glass is applied on a substrate to cut or partially cut the substrate with high production efficiency, low production cost and good environmental protection. The cutting method of the present invention comprises a step of driving at least a particle beam composed of particles of metallic glass from a particle feeder to impact or collide with the substrate to cut or partially cut the substrate.

Description

CUTTING METHOD BY USING PARTICLE BEAM OF METALLIC GLASS

Conventional shot peening can be applied to process or cut a substrate by using steel balls, ceramic balls or carborundum particles. However, this conventional pinning method has the following disadvantages.

1. The pinning ball or particle has low hardness, low density and acute angles, which may cause destruction of the substrate being processed or cut by the pinning ball or particle.

2. The pinning balls or pinning particles have low breaking strength and toughness, so they are easily broken after peening, making them unsuitable for recycling.

3. Shot peening, when carried out by wet process, will increase the difficulty of treatment of processing sludge waste, thereby affecting environmental protection.

4. Productivity may be lowered due to easy destruction or damage of the pinned substrate, and the product value may be lowered by increasing the production cost.

The inventors discovered the disadvantages of the conventional peening process and invented the cutting method of the present invention with improved production efficiency and reduced production cost.

It is an object of the present invention to provide a cutting method in which a particle beam of metallic glass is applied on a substrate to cut or partially cut the substrate with high production efficiency, low production cost and good environmental protection.

1 shows an illustration of a first preferred embodiment according to the invention;
2 is a view showing a wafer to be cut according to the present invention.
3 shows a second preferred embodiment according to the invention.
4 shows a third preferred embodiment according to the invention.

1 and 2, a first preferred embodiment of the present invention comprises a particle feeder 1 for feeding particles of metallic glass 10 to a nozzle 2 formed in a lower part of the feeder 1, , air or an inert gas, for example nitrogen or argon, when boosted by a driving gas (G) downwards to form a particle beam (4) to impinge against the substrate (5). Disclosed is a cutting equipment comprising a spray barrel (3) formed in the bottom portion of the nozzle (2) to spray into the

The particle feeder 1 and the substrate 5 are placed in a negative pressure environment E, and are thus provided in an enclosed chamber evacuated to form a negative pressure environment.

The pressure of the driving gas may be set in the range of 0.1 bar to 5 bar, but the present invention is not limited thereto.

The particle size of metallic glass can range from 1 to 100 microns for precision cutting operations.

The metallic glass may be selected from an iron-based metallic glass, a nickel-based metallic glass, a cobalt-based metallic glass, and a metallic glass having a high entropy alloy.

The substrate 5 may be a wafer disposed on the substrate 5 and having a plurality of chips 52 arranged as an array. After being bombarded by the particle beam 4 of metallic glass, a plurality of cutting channels 51 are defined and each chip 52 is surrounded by and defined by a plurality of cutting channels 51 as shown in FIG. 2 . It will be formed on the substrate 5 as much as possible. Each cutting channel 51 is recessed downward from the substrate 5 to retain a thin bottom layer 51a ( FIG. 1 ) to link together neighboring chips 52 without breaking and separating. During the impact or impact of the particle beams 4 of metallic glass onto the substrate 5 , each chip 52 is covered by a mask 53 for protection of the chip. After cutting (impact) by the metallic glass, scraps 50 will be formed as shown in FIG. 2 . The chip 52 includes a semiconductor chip, an LED chip, and the like.

The above-mentioned impact of particles of metallic glass on the substrate 5 can be defined as a cutting operation. This cutting is not performed to completely cut the substrate 5, that is, the thin bottom layer 51a is still maintained (Fig. 1). This can help reliable and safer transfer of chips 52 disposed on a “partially cut” substrate 5 for further processing of the chips 52 . After transporting the chips 52 for further processing, the previously linked and not fully cleaved chips 52 will then be completely destroyed and separated along the cleavage channels 51 .

Otherwise, if the chips 52 were completely cut during the impact (cutting) operation, the separated chips 52 would be difficult to handle for further processing such as packaging of the chips.

In the present invention, the particle beam of metallic glass is forcibly driven by gas under a pressure of 0.1 to 5 bar to collide with the substrate or plastically depression the substrate by applying an impact to the substrate to form a plurality of cutting channels 51, By allowing each chip 52 to be surrounded by a plurality of cleavage channels 51 by defining the chips 52 of

Due to the excellent properties of the metallic glass particles 10 as used in the present invention, namely, small particle size, high hardness, high density, and high roundness are used. The impact particle of metallic glass with its high dynamic impact energy will collectively sink the substrate to form a plurality of cutting channels 51 , which is advantageous for further cutting and separation of the chips 52 . The metallic glass particles have high breaking strength and are not easily broken, so that the metallic glass particles can be recycled and reused for cost reduction and better environmental protection.

The thickness of the thin lower layer 51a may be 0.02 mm to 0.1 mm, but the present invention is not limited thereto.

The depth of the cutting channel 51 can be set or adjusted by changing parameters including impact speed, impact distance, impact angle, impact time and production capacity of metallic glass particles. However, each cutting channel 51 can be formed to have a precise depth, retaining only a thin bottom layer 51a, which is intended to facilitate the peeling and separation of each chip 52 from the substrate 5 . The thin bottom layer 51a can link neighboring chips 52 without being completely destroyed or separated, which can help smooth and reliable transfer of chips 52 for further processing of the chips. In subsequent processing, each thin bottom layer 51a can be delaminated and broken to separate the chips 52 .

As shown in Fig. 3, the particle feeder was changed to a centrifugal particle feeder 1a. Via this centrifugal particle feeder 1a, the particles 10 feed the substrate ( 5) can be centrifugally thrust to impact

As shown in Fig. 4, another particle feeder 1b is provided comprising a first electrode 11 and a second electrode 13, said first electrode 11 and second electrode 13 being Charged particles of metallic glass 10 between the two electrodes 11 , 13 by causing an electric current to be supplied thereto and forming a voltage V across the first electrode 11 and the second electrode 13 . connected to form an electrical circuit that generates them. A first electrode (11) is formed on the upper stream of particles (10) entering the feeder (1b), while a second electrode (13) is formed on the substrate (5) opposite the first electrode (11). do. At least the electromagnetic coil 12 surrounds the nozzle 2 and the discharge barrel 3 to further accelerate the charged particles 10 to form strong particle beams 4 downwardly relative to the substrate 5 . It is provided to boost the impact to form a plurality of cutting channels (51).

The other particle feeders 1 can be further modified to boost the particle beam to efficiently cut the channels 51 in the substrate 5 .

The present invention is superior to the conventional shot peening process with the following advantages:

1. Due to the high hardness and high roundness of the metallic glass particles, it will not cause unexpected breakage even in the small cracks of the substrate, thereby preventing the uncontrolled destruction of the wafer to be cut.

2. Metallic glass particles can be used for large cutting area when cutting substrates (including wafers) to improve cutting efficiency.

3. After “partial cutting” of the substrate (wafer), the thin bottom layer 51a linking neighboring chips can help safe, smooth and reliable transfer of the partially cut wafer for further processing. Thereafter, the chips can be easily peeled off and separated from the partially cut wafer only by breaking the thin respective bottom layer 51a. Therefore, productivity and commercial value will increase significantly.

4. This method is particularly suitable for cutting mini or micro LEDs to shorten the cutting time and to facilitate mass transfer of LED chips for further processing.

5. No wet process is used. No corrosive chemicals such as hydrofluoric acid are used. Therefore, pollution risk does not occur and it is better for environmental protection.

The present invention may be further modified without departing from the spirit and scope of the present invention.

Claims (9)

A cutting method comprising:
and driving at least a particle beam composed of particles of metallic glass from a particle feeder to impact or impinge the substrate to cut or partially cut the substrate. The method of claim 1,
The particle feeder includes a nozzle coupled to the feeder, and a spray barrel coupled to the nozzle, whereby when driving the particle beam by a driving gas comprising air and an inert gas, the particle beam cuts the substrate. or driven to impinge the substrate to partially cut. The method of claim 1,
The cutting method is performed in a negative pressure environment. 3. The method of claim 2,
The motive gas has a pressure range of 0.1 bar to 5 bar. The method of claim 1,
wherein the substrate is a wafer and the particle beam partially cleaves the substrate to form a plurality of cleavage channels to define a plurality of chips, having a thin bottom layer formed among a plurality of neighboring chips for linking the chips. and wherein each of said chips is covered with a mask for protecting said chips during a cutting operation. 6. The method of claim 5,
The thin bottom layer is adapted to reliably transport the substrate when partially cut so that upon peeling and breaking of each of the thin bottom layers, the chips can be easily separated from each other for further processing. , cutting method. The method of claim 1,
wherein the particle beam of particles of metallic glass is driven by a centrifugal particle feeder for centrifugally boosting the particle beam to impinge on the substrate to cut the substrate. The method of claim 1,
the particle beam is driven by a particle feeder,
The particle feeder includes: a first electrode formed upstream of the feeder; a second electrode formed on the substrate opposite to the first electrode; an electrical circuit connected between the first electrode and the second electrode, wherein an electric current is supplied to the circuit to form charged particles of metallic glass between the first electrode and the second electrode and causing a voltage to be formed between the first electrode and the second electrode; and at least an electromagnetic coil surrounding the feeder to impact the substrate and accelerate the charged particles toward downstream of the feeder to cut the substrate. 6. The method of claim 5,
The chip includes a semiconductor chip, a computer chip, an LED chip, a mini LED chip, a micro LED chip and other electronic chips.

Images