Method for attaching and detaching substrates during integrated circuit manufacturing

Abstract

To provide a method for attaching and detaching substrates during integrated circuit manufacturing.SOLUTION: A method for attaching and detaching a substrate from a bonded stack is disclosed. A broadband light-absorbing material is combined with an adhesive material to form a broadband light-absorbing adhesive. The layer of the broadband light-absorbing adhesive is then applied onto one side of a transparent carrier. A substrate is placed on the broadband light-absorbing adhesive and the transparent carrier to form a bonded stack. The substrate can be a wafer or a polymeric film. At this point, processing steps can be performed on the substrate. After the processing steps have been completed, a light pulse from a flashlamp is utilized to heat up the broadband light-absorbing adhesive in order to detach the substrate from the bonded stack, so that the substrate can be easily detached from the bonded stack.SELECTED DRAWING: None

Description

Technical Field

[0001] (Technical Field) The present application generally relates to a method for processing integrated circuits, and more particularly, to a method for attaching and detaching a substrate during integrated circuit manufacturing.

Background Art

[0002] (Background) 3D chip technology has gained high acclaim in the microelectronics industry due to its advantages such as shorter circuit paths, higher performance, lower power consumption, and faster heat dissipation. When using 3D chip technology, multiple heterogeneous silicon wafers can be stacked vertically to form a 3D integrated circuit. The silicon wafers are relatively thin (50 - 100 μm) and can thus be interconnected by utilizing through - silicon vias (TSVs).

[0003] The present disclosure provides a method for attaching and detaching a substrate during the manufacture of a 3D integrated circuit.

Summary of the Invention

Means for Solving the Problems

[0004] (Summary of the Invention) According to one embodiment, a broadband light absorbing material is combined with an adhesive material to form a broadband light absorbing adhesive. A layer of the broadband light absorbing adhesive is then applied on one side of a transmissive carrier. A substrate is placed on the broadband light absorbing adhesive and the transmissive carrier to form a bonded stack. The substrate can be a wafer or a polymer film. At this point, processing steps can be performed on the substrate. For example, the thickness of the wafer can be reduced via a thinning step, or electronic components can be built on the polymer film. After the processing steps are completed, a light pulse from a flash lamp is utilized to heat the broadband light absorbing adhesive in order to separate the substrate from the bonded stack, whereby the substrate can be easily removed from the bonded stack. The substrate is subsequently transported to another station for further processing.

[0005] All features and advantages of the present invention will become apparent in the following detailed written description. The present invention provides, for example, the following items. (Item 1) A method comprising: combining an adhesive material and a light absorbing material to form a broadband light absorbing adhesive; applying a layer of the broadband light absorbing adhesive on one side of a transmissive carrier; placing a wafer on the broadband light absorbing adhesive and the transmissive carrier to form a wafer stack; processing the wafer; applying a light pulse from a flash lamp to heat the broadband light absorbing adhesive layer in order to release the wafer from the wafer stack. The method as described above. (Item 2) The method according to Item 1, wherein the light absorbing material is a dye. (Item 3) The method according to Item 1, wherein the light absorbing material is a coloring material. (Item 4) ​The method according to item 3, wherein the coloring material is carbon black. (Item 5) The method according to item 1, wherein the carrier is made of quartz. (Item 6) The method according to item 1, wherein the carrier is made of glass. (Item 7) The method according to item 1, wherein the combining further includes combining an adhesive material, a light absorption material, and a gas generation material to form a broadband light absorption adhesive. (Item 8) The method according to item 6, wherein the gas generation material is a material that sublimates or boils at a temperature lower than the boiling temperature of the adhesive material. (Item 9) The method according to item 6, wherein the gas generation material is a sublimable dye. (Item 10) The method according to item 1, wherein the broadband light absorption adhesive absorbs more than 80% of the light pulse from the flash lamp and transmits 1 - 10% of the light pulse from the flash lamp. (Item 11) A method comprising: Combining an adhesive material and a light absorption material to form a broadband light absorption adhesive; Applying a layer of the broadband light absorption adhesive onto one side of a transmissive carrier; Placing a polymer film on the broadband light absorption adhesive and the transmissive carrier to form a stack of polymer films; Processing the polymer film; Applying a light pulse from a flash lamp to heat the broadband light absorption adhesive layer to release the polymer film from the stack of polymer films. A method comprising the above steps. (Item 12) The method according to item 11, wherein the light absorption material is a dye. (Item 13) The method according to item 11, wherein the light absorption material is a coloring material. (Item 14) The method according to item 13, wherein the coloring material is carbon black. (Item 15) The method according to item 11, wherein the carrier is made of quartz. (Item 16) The method according to item 11, wherein the carrier is made of glass. (Item 17) The method according to item 11, wherein the combining further includes combining an adhesive material, a light absorption material, and a gas generation material to form a broadband light absorption adhesive. (Item 18) The method according to item 16, wherein the gas generation material is a material that sublimates or boils at a temperature lower than the boiling temperature of the adhesive material. (Item 19) The method according to item 16, wherein the gas generation material is a sublimable dye. (Item 20) The method according to item 11, wherein the broadband light absorption adhesive absorbs more than 80% of the light pulse from the flash lamp and transmits 1 to 10% of the light pulse from the flash lamp.

Brief Description of the Drawings

[0006] The present invention itself, as well as preferred modes of use, further objects, and their advantages, will be best understood by reference to the following detailed description of the exemplary embodiments when read in conjunction with the accompanying drawings.

[0007]

Figure 1

[0008]

Figure 1A

[0009]

Figure 1B

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Figure 2

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Figure 2A

[0012]

Figure 2B

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Figure 3

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Figure 4

[0015] (Detailed Description of the Preferred Embodiment) During the manufacture of three-dimensional (3D) integrated circuits, in order to reduce the thickness of silicon wafers, a thinning step is required to be performed on each silicon wafer of the 3D integrated circuit. The silicon wafer can be attached to a rigid carrier via an adhesive that is placed directly between the silicon wafer and the rigid carrier prior to the thinning process. After back grinding and all required backside processing have been performed on the silicon wafer, the thinned silicon wafer needs to be removed from the rigid carrier, and thus, the thinned silicon wafer can proceed to other processing steps.

[0016] Current techniques for removing a silicon wafer from a rigid carrier include (a) using a chemical solvent to dissolve the adhesive between the silicon wafer and the carrier, (b) using mechanical means to remove the silicon wafer from the carrier, and (c) heating the adhesive between the silicon wafer and the carrier until the silicon wafer can be easily separated from the carrier by shearing. However, the use of strong chemicals is not very desirable. Also, mechanical means or high temperatures can damage the surface structure of the silicon wafer.

[0017] Referring now to the drawings, and in particular to FIG. 1, there is depicted a flow diagram of a method for attaching and removing a wafer to and from a carrier, according to one embodiment. Beginning at block 100, as shown in block 110, a broadband light absorbing adhesive is first formed by combining an adhesive material that is combined with a broadband light absorbing material.

[0018] The adhesive material may be polar or non-polar. It may be thermoplastic or thermosetting. It may be cured thermally, via ultraviolet light, via a chemical reaction, or formed via solvent evaporation.

[0019] The broadband light absorbing material may be a coloring material such as carbon black that is capable of absorbing across the entire emission spectrum of a flash lamp (i.e., 200 nm to 1,100 nm). The more the broadband light absorbing material is capable of absorbing across the emission range described above, the higher the ratio of the emission from the flash lamp will be converted to heat within the broadband light absorbing adhesive. The light absorbing material may also be a dye or a combination of dyes that absorb a selected portion of the emission spectrum of the flash lamp.

[0020] Alternatively, the broadband light-absorbing adhesive can be formed by combining an adhesive material with a broadband light-absorbing material and a gas-generating material. The adhesive material and the broadband light-absorbing material are the same as those described above. The gas-generating material is a material that sublimates or boils at a temperature lower than the boiling temperature of the adhesive material. Some gas-generating materials can also serve as a light-absorbing material. For example, a sublimable dye can optically absorb light pulses from a flash lamp and, when heated to a specific temperature, sublimate and generate gas.

[0021] The broadband light-absorbing adhesive is then applied as a broadband light-absorbing adhesive layer, such as the broadband light-absorbing adhesive layer 170 in FIG. 1A, on one side of a transmissive rigid carrier, such as the transmissive carrier 160 in FIG. 1A, as depicted in block 120. The carrier 160 may be made of any rigid material that transmits light (200 nm to 1,100 nm) emitted by a quartz, glass, or flash lamp. Exemplary embodiments include Corning Eagle XG glass, a common type of glass used in the display industry.

[0022] Next, the wafer 180 is placed on the broadband light-absorbing adhesive layer 170 as shown in block 130. The wafer 180 includes electronic devices and / or electrical components that are previously constructed on one surface of the wafer 180. Pressure can be applied on the wafer 180 to bond the wafer 180 to the broadband light-absorbing adhesive layer 170 and the carrier 160. The wafer 180 may be heated during the application of pressure on the wafer 180 to increase the adhesive bond between the wafer 180 and the carrier 160. At this point, a bonded wafer stack, such as the bonded wafer stack 190 shown in FIG. 1A, including the transmissive carrier 160, the broadband light-absorbing adhesive layer 170, and the wafer 180, is formed.

[0023] The wafer 180 of the wafer stack 190 then undergoes a back thinning process to reduce the thickness of the wafer 180 as depicted in block 140. Thereafter, the wafer 180 is removed (debonded) from the bonded wafer stack 190 by exposing the non-wafer side of the transmissive carrier 160 to a powerful pulse of light from a flash lamp such as the flash lamp 350 in FIG. 1B to heat the broadband light-absorbing adhesive layer 170 as shown in block 150. As a result, the broadband light-absorbing adhesive layer 170 is heated to the point where the wafer 180 will be released from the bonded wafer stack 190 as shown in block 150.

[0024] When a gas-generating material is added to the adhesive layer 170, the gas-generating material can generate gas at the interface between the carrier 160 and the adhesive layer 170 to facilitate the peeling of the adhesive layer 170 from the carrier 160 when the adhesive layer 170 reaches a specific temperature. The gas-generating material becomes gaseous at a temperature lower than that of the polymer system of the adhesive material. When the presence of the gas-generating material is involved, since this is only a trace additive, the temperature at which the gas is generated can be separated from the other thermal and mechanical properties of the adhesive material.

[0025] (Example 1) 10 g of poly(2-ethyl-2-oxazoline), a water-soluble thermoplastic polymer available from Aquazol (Grade 5), was added to 10 g of a 5 wt% aqueous solution of carbon black (Cabot Monarch® 700) to form a composition. The composition was mixed using a dual-rotation stirrer at 2,000 rpm for 20 minutes. The resulting mixture was a homogeneous, black, and viscous liquid dispersion that could be utilized as a broadband light-absorbing adhesive. The dispersion (i.e., the broadband light-absorbing adhesive) was coated onto a 0.5 mm thick Corning Eagle XG glass measuring 75 mm × 75 mm using a #0 Mayer rod and a 100 micron thick tape spacer to coat a wet film with a thickness of approximately 100 microns. The dispersion was then dried at 140 °C for 30 minutes to obtain a black light-absorbing film that adhered to the Corning Eagle XG glass with a thickness of approximately 50 microns. The transmittance of the film was measured to be less than 1% via an X-Rite® densitometer. Next, a second piece of Corning Eagle XG glass was compression-bonded to the first piece of Corning Eagle XG glass with the dried dispersion in between by applying a 2.5 Kg weight on the stack. Meanwhile, the stack was heated at 220 °C for 40 minutes to melt the polymer and bond the two pieces of glass together. Next, the stack was illuminated from the coated glass side using a flash lamp (PulseForge® Invent model IX2-951 manufactured by NovaCentrix®). The threshold for removing the two pieces of glass was at a charging voltage of 950 V with a pulse duration of 80 microseconds. This condition deposited an energy of 1.86 J / cm 2 onto the bonded stack. After irradiation, delamination occurred at the interface of the flash lamp facing the glass and the adhesive.

[0026] Note that the thinner the wafer, the easier it is for the wafer to be removed from the carrier plate. This is because the wafer is highly thermally conductive. Silicon, for example, has a thermal conductivity of about 140 W / cm-K, which is more than 100 times higher than that of a carrier plate such as glass. Therefore, most of the energy from the light absorption layer is conducted through the adhesive layer to the wafer during the 50 - 150 microseconds when the absorber is irradiated by the light pulse. When the adhesive layer reaches the removal temperature, it will be in a state of being removed from the carrier. The thinner the wafer, the faster the adhesive reaches the removal temperature. Therefore, a thinner wafer can be removed using a shorter pulse of light at the same strength. One advantage is that less energy is required to perform the removal process. In addition, the shorter duration increases the lifetime of the flash lamp. The intensity of the light emission from the flash lamp can be reduced for a given pulse length, which also reduces the total amount of energy deposited in the wafer.

[0027] The minimum removal threshold of the adhesive from the glass carrier can be determined by omitting a second piece of glass that absorbs part of the thermal energy from the light pulse. The measured threshold of adhesive removal is at a charging voltage of 950 V with a pulse duration of 70 microseconds, and this condition corresponds to a radiant exposure of 1.53 J / cm 2 emitted by the flash lamp.

[0028] The removal threshold of the adhesive from the glass carrier is measured again by adding 2% ethylene glycol to the adhesive. The measured threshold of adhesive removal is at a charging voltage of 950 V with a pulse duration of 65 microseconds, and this condition corresponds to a radiant exposure of 1.40 J / cm 2It corresponds to the radiant exposure. Regarding peeling, the threshold value reduced beyond the results described above is considered to be the addition of ethylene glycol, which acts as a gas generation material. Ethylene glycol boils at 197 °C, while the higher temperature aquasol is thermally stable even above 300 °C.

[0029] The broadband light-absorbing adhesive layer 170 has good absorption of the light pulse from the flash lamp while having sufficient transmittance to enable alignment of the wafer 180 on the carrier 160. Even a transmittance of 0.1% through the adhesive layer 170 is sufficient for alignment, but preferably a transmittance above 1% or even higher than 10% is sufficient for easy alignment such that the light pulse from the flash lamp does not harm the wafer 180 during the removal process. For example, the adhesive layer 170 absorbs more than 80% of the light pulse emission from the flash lamp for wafer alignment while allowing 1% - 10% of the light pulse emission to pass through.

[0030] In addition to wafers, the present invention is also applicable to polymer films on which electronic devices can be processed.

[0031] Referring now to FIG. 2, a flow diagram of a method for attaching and then removing a polymer film to and from a carrier according to one embodiment is depicted. Starting from block 200, as shown in block 210, the broadband light-absorbing adhesive is initially formed by combining an adhesive material that is combined with a broadband light-absorbing material.

[0032] The adhesive material may be polar or non-polar. It may be thermoplastic or thermosetting. It may be cured thermally, via ultraviolet light, via a chemical reaction, or may be formed via solvent evaporation.

[0033] The broadband light-absorbing material is a coloring material such as carbon black. Alternatively, the light-absorbing material may be a dye or a combination of dyes.

[0034] Alternatively, the broadband light absorbing adhesive can be formed by combining an adhesive material with a broadband light absorbing material and a gas generating material. The adhesive material and the broadband light absorbing material are the same as those described above. The gas generating material is a material that sublimates or boils at a temperature lower than the boiling temperature of the adhesive material. Some gas generating materials can also serve as light absorbing materials. For example, sublimable dyes can optically absorb the beam from the flash lamp and, when heated to a certain temperature, sublimate and generate gas.

[0035] The broadband light absorbing adhesive is then applied as a broadband light absorbing adhesive layer, such as the broadband light absorbing adhesive layer 270 in FIG. 2A, to one side of a transmissive rigid carrier, such as the transmissive carrier 260 in FIG. 2A, as depicted in block 220. The carrier 260 may be made of any rigid material that transmits light emitted by a quartz, glass, or flash lamp. Exemplary embodiments include Corning Eagle XG glass, a common type of glass used in the display industry.

[0036] Next, a polymer film 280 is placed on the broadband light absorbing adhesive layer 270, as shown in block 230. Pressure can be applied onto the polymer film 280 to bond the polymer film 280 to the broadband light absorbing adhesive layer 270 and the carrier 260. The polymer film 280 may be heated during the application of pressure onto the polymer film 280 to increase the adhesive bond between the polymer film 280 and the carrier 260. At this point, a polymer film stack, such as the polymer film stack 290 shown in FIG. 2A, is formed, which includes the transmissive carrier 260, the broadband light absorbing adhesive layer 270, and the polymer film 280.

[0037] The electronic device and / or electrical component is then constructed on one surface of the polymer film 280 as depicted in block 240. The polymer film 280 is then removed (debonded) from the polymer film stack 290 by exposing the non-wafer side of the transmissive carrier 260 to a powerful pulse of light from a flash lamp such as the flash lamp 350 in FIG. 2B to heat the broadband light-absorbing adhesive layer 270. As a result, the broadband light-absorbing adhesive layer 270 is heated to the point where the polymer film 280 will be released from the polymer film stack 290 as shown in block 250.

[0038] Any remaining adhesive layer 270 can be washed using a solvent, leaving only the polymer film stack 290 with an electronic structure. For example, polyamic acid can be deposited on the adhesive and thermally cured to produce a thin layer of polyimide on the adhesive. Electronic materials can then be deposited and cured on the polyimide, and components can be placed and soldered to produce the final structure. This technique enables the ability to process electronic components on ultrathin films of polymers with thicknesses in the range of 3 to 30 microns.

[0039] Referring now to FIG. 3, there is depicted a block diagram of an apparatus for effecting removal of a substrate from a carrier, according to one embodiment. As shown, apparatus 300 includes a flash lamp control unit 301 and a removal unit 302. The flash lamp control unit 301 includes a capacitor bank charging power supply 310, a capacitor bank 320, an insulated gate bipolar transistor (IGBT)-based switching device 330, a frequency controller 340, a photodiode 360, a bolometer 370, an integrator 380, and a computer 390. The computer 390 includes a processor and various memory devices well known to those skilled in the art. The capacitors within capacitor bank 320 are, for example, electrolytic capacitors. The capacitors within capacitor bank 320 may also be pulse discharge capacitors. Capacitor bank 320 may alternatively be switched using a silicon controlled rectifier (SCR) switching device.

[0040] Capacitor bank 320 can be charged by capacitor bank charging power supply 310. Current from capacitor bank 320 is then discharged into flash lamp 350 via IGBT-based switching device 330, while IGBT-based switching device 330 is repeatedly switched on and off by frequency controller 340 during the discharge. The frequency controller 340 controls the gating of the IGBT-based switching device 330, which in turn controls the switching frequency of the discharge. The repeated on and off switching of the IGBT-based switching device 330 is intended to modulate the flow of current from capacitor bank 320 to flash lamp 350, which in turn switches flash lamp 350 on and off. In other words, the frequency or pulse length of the light pulses emitted by flash lamp 350 is determined by frequency controller 340.

[0041] The photodiode 360 within the flash lamp control unit 301 needs to be calibrated before operation. The photodiode 360 can be calibrated by using a bolometer 370 that is traceable to the National Institute of Standards and Technology (NIST) in the United States. During calibration, both the photodiode 360 and the bolometer 370 are exposed to a single light pulse emitted from the flash lamp 350. The bolometer 370 measures the radiant exposure or energy (in units of J / cm 2 ) per unit area of the single light pulse, and the photodiode 360 measures the instantaneous power density (in units of W / cm 2 ) of the same light pulse. The instantaneous power density signal from the photodiode 360 is then integrated by an integrator 380 to yield the radiant exposure value of the same single light pulse. The radiant exposure measurement from the bolometer 370 is divided by the this radiant exposure value from the integrator 380 to generate a calibration factor as follows.

Equation

[0042] After calibration, the photodiode 360 / integrator 380 combination can be utilized to provide radiant exposure information for each light pulse emitted from the flash lamp 350. Basically, the radiant exposure information of the light pulse emitted from the flash lamp 350 can be calculated by multiplying the calibration factor obtained during calibration by the output value of the integrator 380 (which is the radiant exposure value of the light pulse emitted from the flash lamp 350 formed by integrating the instantaneous power signal of the light pulse emitted from the flash lamp 350 measured by the photodiode 360).

[0043] The removal unit 302 includes a feeding robot 352, a removal vacuum table 354, and a vacuum gripper 356.

[0044] Prior to removal, the dicing tape 410 is mechanically crimped to the wafer stack 190 via the holding ring 420, as shown in FIG. 4, to form a bonded wafer assembly. The wafer feeding robot 352 transports the bonded wafer assembly to the removal vacuum table 354. Vacuum is then applied from the removal vacuum table 354 onto the dicing tape 410. Then, an optical pulse from the flash lamp 350 is used to illuminate the bonded wafer assembly from the transparent side of the carrier 160 and remove the processed wafer 180 from the carrier 160. If the beam area of the flash lamp 350 is smaller than the area of the wafer 180, the wafer 180 is transported relative to the flash lamp 350 by removing the vacuum table 354 and exposing the remaining portion of the wafer 180 using another optical pulse. Next, the wafer assembly bonded with the removal table 354 is transported to the separation station.

[0045] At the separation station, the vacuum gripper 356 separates the carrier 160 from the bonded wafer assembly, while the wafer 180 mounted on the dicing tape 410 is pressed downward by removing the vacuum table 354. Both the carrier 160 and the wafer 180 on the dicing tape 410 are transported to the cleaning station to remove any residual adhesive (i.e., the adhesive layer 170 from FIG. 1A). The residual adhesive may be removed using a wet process via a solvent or a dry process using plasma.

[0046] At this point, since the wafer 180 is very fragile, the vacuum applied to the wafer 180 should be dispersed across it so as not to break the wafer 180 during removal. This may be accomplished using a plurality of suction cups 430 that are dispersed across the surface of the wafer 180, as depicted in FIG. 4. Alternatively, the vacuum may be applied by distributed vacuum such as a vacuum table with perforated holes. The vacuum table 354 may have a polymer on its surface, and thus the wafer 180 is not damaged during handling.

[0047] During the external process, the apparatus 300 can have five lamp drivers per flash lamp, using lamps with a diameter of 24 mm and a length of 150 mm, with an exposure area of 150 mm × 75 mm per lamp. The flash lamps are installed parallel to each other and can increase the exposure area in 75 mm increments. For example, two flash lamps provide an exposure area of 150 mm × 150 mm, three flash lamps provide an exposure area of 150 mm × 225 mm, four flash lamps provide an exposure area of 150 mm × 300 mm, and so on. The flash lamps are installed within a common optical resonator, and the exposure is uniform within 3%. The flash lamp driver contains a capacitor and an IGBT. The current from the capacitor is switched to the flash lamp by the IGBT. The lamp drivers may be installed in parallel with each other to increase the peak current supplied to the flash lamp. The variables of the flash lamp system are the charging voltage of the capacitor, the total capacitance determined by the number of flash lamp drivers, and the length of the light pulse switched on and off by the IGBT. All parameters are controlled by a computer. The silicon wafer is detached from the glass carrier plate at 900 - 950 V with a pulse duration of 50 - 150 microseconds, which can correspond to 1 - 6 J / cm 2 The peak radiant power of the flash lamp 350 exceeds 20 KW / cm 2 and more preferably exceeds 30 KW / cm 2 and even more preferably exceeds 40 KW / cm 2 .

[0048] As described, the present invention provides an improved method for removing a substrate from a carrier. One advantage of this method is that the carrier 210 does not need to be sputtered with a light-absorbing layer, which not only simplifies the process's supply chain management but also potentially saves funds. Another advantage of this method is that the absorption rate of the adhesive can be made higher than that of a typical sputtered metal. For example, tungsten can only absorb about 45% of the flash lamp emission. This allows for reduced energy in the flash lamp emission required to reach the same temperature within the light-absorbing body. This, in turn, increases the lifetime of the flash lamp. Additionally, this method allows for the pulse length of the flash lamp emission to be decreased. This reduces the heat diffusion to the substrate and the carrier during the removal process, thus reducing both the thermal shock and the total thermal budget to the substrate.

[0049] The present invention has been shown and described with reference to particular preferred embodiments, but it will be understood by those skilled in the art that various changes in form and detail may be made therein without departing from the spirit and scope of the invention.

Claims

**Claim 1** A method comprising: providing a broadband light-absorbing adhesive mixture comprising a broadband light-absorbing material and a gas-generating material; applying a layer of the broadband light-absorbing adhesive mixture onto one side of a light-transmissive carrier; placing a wafer on the broadband light-absorbing adhesive mixture and the light-transmissive carrier to form a wafer stack; processing the wafer; applying a light pulse from a flash lamp to heat the broadband light-absorbing adhesive mixture layer to release the wafer from the wafer stack. A method as described above. **Claim 2** The method according to claim 1, wherein the light-absorbing material is a dye. **Claim 3** The method according to claim 1, wherein the light-absorbing material is a coloring material. **Claim 4** The method according to claim 3, wherein the coloring material is carbon black. **Claim 5** The method according to claim 1, wherein the carrier is made of quartz. **Claim 6** The method according to claim 1, wherein the carrier is made of glass. **Claim 7** The method according to claim 1, wherein the gas-generating material comprises ethylene glycol. **Claim 8** The method according to claim 1, wherein the gas-generating material is a sublimable dye. **Claim 9** The method according to claim 1, wherein the broadband light-absorbing adhesive mixture absorbs more than 80% of the light pulse from the flash lamp and transmits 1-10% of the light pulse from the flash lamp. **Claim 10** A method comprising: providing a broadband light-absorbing adhesive mixture comprising a broadband light-absorbing material and a gas-generating material; applying a layer of the broadband light-absorbing adhesive mixture onto one side of a light-transmissive carrier; placing a polymer film on the broadband light-absorbing adhesive mixture and the light-transmissive carrier to form a polymer film stack; processing the polymer film; applying a light pulse from a flash lamp to heat the broadband light-absorbing adhesive mixture layer to release the polymer film from the polymer film stack. A method as described above. **Claim 11** The method according to claim 10, wherein the light-absorbing material is a dye. **Claim 12** The method according to claim 10, wherein the light-absorbing material is a coloring material. **Claim 13** The method according to claim 12, wherein the coloring material is carbon black. **Claim 14** The method according to claim 10, wherein the carrier is made of quartz.

15. The method according to claim 10, wherein the carrier is made of glass.

16. The method according to claim 10, wherein the gas generating material contains ethylene glycol.

17. The method according to claim 10, wherein the gas generating material is a sublimable dye.

18. The method according to claim 10, wherein the broadband light-absorbing adhesive mixture absorbs more than 80% of the light pulse from the flash lamp and transmits 1 to 10% of the light pulse from the flash lamp.

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