High-density packaging is an advanced integrated circuit packaging technology that can integrate more chips into a smaller package, thereby improving the integration and performance of the device. The main advantages of this technology include higher integration, smaller size, higher performance, and lower energy consumption. Its main features are as follows:

　　1. Improved Integration

　　High-density packaging technology can integrate more chips and components in a smaller space, thereby improving the integration and functional density of electronic devices.

　　2. Reduced Size

　　High-density packaging technology can effectively reduce the package size, thereby reducing the volume and weight of the entire electronic device.

　　3. Improved Performance

　　High-density packaging technology can reduce signal transmission delay, improve electrical performance, and improve the reliability and stability of the device.

　　4. Lower Cost

　　1 Semiconductor packaging technology continues to develop, with multiple types of bonding

　　Bonding mainly serves to combine two wafers, with various classification standards.

　　⚫ Bonding is a process of joining two smooth and clean wafer surfaces together through physical or chemical methods to assist in semiconductor manufacturing processes or to form heterogeneous composite wafers with specific functions. There are many types of bonding technologies. Generally, according to the target type of wafer, they can be divided into wafer-to-wafer (W2W) bonding and die-to-wafer (D2W) bonding; according to whether debonding is required after bonding, they can be divided into temporary bonding and permanent bonding; according to whether an auxiliary interface layer is introduced between the wafers to be bonded, they can be divided into direct bonding, indirect bonding, and hybrid bonding; according to whether they are traditional or advanced, traditional methods include wire bonding, while advanced methods use flip chip bonding, hybrid bonding, etc.

　　2 Traditional packaging methods mainly use wire bonding to achieve electrical interconnection.

　　Traditional packaging relies on wire bonding to achieve electrical connections and can be divided into through-hole mounting and surface mounting types.

　　⚫ Traditional packaging relies on wires to electrically connect the wafer to the outside world. After the wafer is diced into dies, the dies are attached to the corresponding substrate frame, and then wires are used to connect the bonding pads of the chip to the substrate pins to achieve electrical connection. Finally, the assembly is protected by an outer casing.

　　⚫ Traditional packaging can be roughly divided into through-hole mounting and surface mounting packaging. In the 1970s, people usually used through-hole technologies such as dual in-line packages (DIP) or zigzag single in-line packages (ZIP), which involved inserting leads into mounting holes on the printed circuit board (PCB). Later, with the increasing number of pins and the increasing complexity of PCB design, the limitations of through-hole mounting technology became increasingly apparent, and surface mounting technologies such as thin small outline packages (TSOP), quad flat packages (QFP), and J-lead small outline packages (SOJ) were successively introduced.

　　Traditional packaging relies on wire bonding to achieve electrical connections and can be divided into through-hole mounting and surface mounting types.

　　⚫ Wire bonding can be divided into thermocompression bonding, ultrasonic bonding, and thermosonic bonding according to the different bonding energy used. (1) Thermocompression bonding: A micro-arc is used to melt the end of the bonding wire into a ball shape, and a wire-feeding pressure head is used to weld it to the lead terminal to form the first bonding point; then the wire-feeding pressure head is lifted and moved to form the second bonding point on the corresponding conductor wiring terminal of the wiring board, completing the wire connection process. (2) Ultrasonic bonding: Ultrasonic bonding is mainly used for the wire bonding of aluminum wires. The dislocation in the aluminum wire selectively absorbs the ultrasonic energy, so that the aluminum wire can be in a plastic deformation state under very low external force. The oxide film formed on the surface of the aluminum evaporation film is destroyed, exposing a clean metal surface for bonding. (3) Thermosonic bonding: A heater is introduced into the ultrasonic bonding machine for auxiliary heating. The bonding tool uses a wire-feeding pressure head and performs ultrasonic vibration, which has higher efficiency and wider applications, but the process is more complex.

　　Overseas K&S and ASMPT are the leading companies in wire bonding machines, with a combined market share of approximately 80%.

　　⚫ Affected by downstream demand and the acceleration of domestic substitution by Chinese equipment manufacturers, the import market space for wire bonding machines in China in 2024 is approximately US$618 million, which is significantly lower than the peak import market space of US$1.59 billion in 2021. Imported wire bonding machines include gold/copper wire bonding machines and aluminum wire bonding machines. Among them, the number of aluminum wire bonding machines accounts for about 10-15%, approximately 3000-4000 units, with a unit value of about US$250,000, and a market space of about RMB 4-5 billion; the number of gold/copper wire bonding machines accounts for about 85-90%, with a lower unit value of about US$5-60,000, and a market space of about RMB 8 billion.

　　⚫ Overseas K&S (Kulicke and Soffa) and ASM are the leading companies in semiconductor bonding machines, with a combined market share of approximately 80% in 2021. The aluminum wire bonding machine is the OE business of an American company acquired by K&S in 2010. The bonding machine itself also belongs to welding, which is in line with K&S's production culture. Before 2020, K&S's market share in the automotive electronics and power devices market, especially the automotive electronics market, was as high as 90%. K&S's Asterion and PowerFusion products are highly competitive; since the second half of 2020, competitors such as ASMPT and Auotive have emerged, and K&S is gradually reducing its investment in the IGBT market for power devices and shifting its focus to automotive electronics. The price of a single unit from foreign leading companies is US$250,000 (approximately RMB 1.8 million), while domestic equipment costs around RMB 1.3 million.

　　3 Advanced packaging is developing rapidly, with thermocompression bonding and hybrid bonding being future trends.

　　In the post-Moore's Law era, packaging pursues higher transmission speeds and smaller chip sizes.

　　⚫ Packaging is gradually developing towards high-speed signal transmission, stacking, miniaturization, low cost, high reliability, heat dissipation, etc. (1) High-speed signal transmission: Technologies such as artificial intelligence and 5G require improvements in semiconductor packaging technology to improve transmission speed while increasing chip speed; (2) Stacking: In the past, only one chip was contained in one packaging shell, but now multiple chips can be stacked in one packaging shell using technologies such as multi-chip packaging (MCP) and system-in-package (SiP); (3) Miniaturization: As semiconductor products are gradually used in mobile and even wearable products, miniaturization has become an important requirement.

　　Bonding methods are gradually transitioning from wire bonding, flip-chip bonding, thermocompression bonding to hybrid bonding.

　　Under the evolution of packaging forms, bonding technology pursues smaller interconnect distances to achieve faster transmission speeds. Packaging technology has evolved from the initial use of lead frames to flip-chip (FC), thermo-compression bonding (TCB), fan-out packaging, and hybrid bonding to integrate more I/O, reduce thickness, support more complex chip functions, and adapt to thinner and lighter mobile devices. Under the latest hybrid bonding technology, bonding accuracy has improved from 5-10/mm² to 10k+/mm², and precision from 20-10μm to 0.5-0.1μm, while energy/bit has been further reduced to 0.05pJ/bit.

　　Bonding methods are gradually transitioning from wire bonding, flip-chip bonding, thermocompression bonding to hybrid bonding.

　　To reduce chip size, the package size and bump pitch need to be reduced accordingly; a 10μm bump pitch provides approximately 400 times more I/O than a 200μm bump pitch. As electronic devices move towards lighter, thinner, smaller, and higher-performance designs, bump pitch has advanced to 20μm, and some industry giants have achieved bump pitches of less than 10μm; a 10μm bump pitch provides approximately 400 times more I/O than a 200μm bump pitch.

　　A 50-40μm bump pitch can be achieved through flip-chip bonding, a 40-10μm bump pitch requires thermo-compression bonding (TCB), and a bump pitch below 10μm requires hybrid bonding. (1) Flip-chip bonding's reflow soldering is suitable for 40-50μm bump pitches, but as the bump pitch decreases, warping and precision problems occur, making reflow soldering unsuitable. (2) Thermo-compression bonding is suitable for 40-10μm bump pitches, but when the bump pitch reaches 10μm, TCB may produce intermetallic compounds, affecting conductivity. (3) High-integration packaging with a bump pitch below 10μm will completely shift to hybrid bonding technology.

　　Flip-chip bonding replaces wire bonding for use in CPU, GPU, and DRAM packaging.

　　Flip-chip bonding achieves electrical and mechanical connection between the chip and substrate through bumps formed on the top of the chip. Like traditional wire bonding, flip-chip packaging technology is an interconnect technology that achieves electrical connection between the chip and substrate. Compared to wire bonding, flip-chip bonding ① has higher connection density; wire bonding can only perform wire connections around the chip, limiting the number and position of input/output (I/O) pins that can be electrically connected, while flip-chip bonding can place bumps across the entire front of the chip, significantly improving connection density; ② has shorter signal transmission paths: flip-chip bonding directly uses bumps for electrical signal transmission, the transmission path is much shorter than wire bonding, resulting in faster computing and transmission capabilities. Therefore, in the field of advanced packaging, flip-chip bonding technology has become the mainstream bonding technology due to its superior electrical performance and space utilization, and is widely used in the packaging of CPU, GPU, and high-speed DRAM chips.

　　Thermo-compression bonding is suitable for ultra-fine pitch, high-density interconnect packaging.

　　To solve the warping and precision problems that occur in the reflow soldering step of flip-chip bonding when the bump pitch is reduced to below 40μm, TCB (Thermal Compression Bonding) becomes the mainstream. TCB bonding uses a high-precision camera to align the chips to be bonded, and by controlling the pressure and displacement of the thermo-compression head to contact the substrate, pressure and heating are applied to achieve bonding between the chips.

　　TCB heats from the top of the chip, only the chip and C4 (Controlled Collapse Chip Connection) solder will heat up, minimizing substrate and wafer warping and tilting problems. Pressure ensures uniform bonding, without gaps or tilting. TCB technology achieves better electrical characteristics at the same I/O pitch and allows for further reduction of I/O pitch, enabling the packaging of thinner chips; therefore, multi-layer HBM3 usually uses TCB.

　　The thermo-compression bonding market is mainly monopolized by overseas companies, with a CR5 of approximately 88%.

　　According to QY Research data, the global thermo-compression bonding (TCB) machine market reached $104 million in 2023 and is expected to reach $265 million by 2030, with a compound annual growth rate of 14.5%. With the development of semiconductor technology towards smaller sizes and higher integration, thermo-compression bonding machines, as core equipment for advanced packaging technology, are in significantly increasing demand. Especially in HBM3 applications, its multi-layer chip stacking technology relies on thermo-compression bonding processes, driving the rapid growth of the thermo-compression bonding machine market.

　　The global thermo-compression bonding machine market is mainly monopolized by overseas companies, with major players including ASMPT, K&S, BESI, Shibaura, and SET. The top five manufacturers account for approximately 88% of the market share (CR5). According to ASMPT's website, its thermo-compression bonding machines include the FIREBIRD TCB series, mainly used for 2D, 2.5D, and 3D packaging of chips in heterogeneous integration, and more than 250 units have been delivered in bulk, making it the leading manufacturer of TCB thermo-compression bonding equipment globally. At the same time, domestic manufacturers such as Huazhuo Jingke and Tangren Manufacturing are also actively developing in this field, and the market share of domestic thermo-compression bonding equipment is expected to gradually expand.

　　Hybrid bonding only requires copper contacts and can achieve higher density interconnections.

　　Hybrid bonding, because its bonding interface contains both metal and dielectric or polymer materials (such as Cu/SiO2, Cu/SiCN, etc.), uses a stacked contact method to combine wafers from different processes to achieve electrical interconnection. Hybrid bonding does not require metal wires or micro-bumps, and only uses copper contacts to achieve short-distance electrical interconnections, promising shorter interconnect distances, higher density, lower cost, and higher performance between chips.

　　Typical Cu/SiO2 hybrid bonding mainly includes three key process steps. (1) Pre-bonding pretreatment: The wafers need to undergo chemical mechanical polishing/planarization (CMP) and surface activation and cleaning to achieve a flat, clean, and hydrophilic surface; (2) Pre-alignment bonding of two wafers: The two wafers are pre-aligned before bonding, and after close contact at room temperature, the dangling bonds on the dielectric SiO2 achieve bridging between the wafers, forming a fused bond between SiO2-SiO2. At this time, there is physical contact or dishing between the metal Cu contacts, and complete metal-metal bonding has not been achieved; (3) Post-bonding annealing: Subsequent annealing promotes the reaction between the dielectric SiO2 between the wafers and the interdiffusion of the metal Cu, thus forming a permanent bond.

　　Hybrid bonding only requires copper contacts and can achieve higher density interconnections.

　　Hybrid bonding logic/memory chips outperform traditional thermo-compression bonding in interconnect density, speed, bandwidth density, energy consumption, and heat dissipation efficiency.

　　Compared to thermocompression bonding chips, hybrid bonding logic chips exhibit superior performance in interconnect density, speed, and bandwidth density, while consuming less power. By comparing AMD's W2W hybrid bonding chip with MI300 using thermocompression bonding, the hybrid bonding chip surpasses MI300 in interconnect density, speed, bandwidth density, and power consumption. (1) Interconnect density is 15 times higher than thermocompression bonding technology, (2) speed is 11.9 times faster, (3) bandwidth density is 191 times higher, and (4) power consumption is 20 times lower.

　　Hybrid bonded HBM chips offer advantages such as low thermal resistance, high signal integrity, low power consumption, and high space utilization. HBM chips using hybrid bonding technology can achieve: (1) a 20% reduction in stacked thermal resistance, significantly improving heat dissipation efficiency; (2) a 20% increase in signal integrity, reducing losses and interference during signal transmission; (3) a 17% reduction in dynamic power consumption, thereby improving overall energy efficiency; (4) an 87% reduction in TSV interconnect area requirements, effectively improving space utilization.

　　Hybrid bonding only requires copper contacts and can achieve higher density interconnections.

　　Hybrid bonding can be divided into wafer-to-wafer (W2W) and die-to-wafer (D2W).

　　(1) W2W is mainly suitable for smaller chips: W2W has a higher yield rate because the alignment and bonding steps are separated, and there are fewer particles, making it cleaner. However, it cannot perform wafer sorting to select known good dies, which can lead to bonding defective dies to good ones.

　　(2) D2W is mainly suitable for large chips and is the first to be industrialized: It has the ability to test and bond known good dies, but it is prone to contamination.

　　Hybrid bonding only requires copper contacts and can achieve higher density interconnections.

　　The main challenges of hybrid bonding technology lie in smoothness, cleanliness, and alignment accuracy.

　　To achieve high-quality bonding, hybrid bonding requires very strict requirements for surface smoothness, cleanliness, and bonding alignment accuracy.

　　(1) Cleanliness: Since hybrid bonding involves bonding two very smooth and flat surfaces together flush, the bonding interface is very sensitive to the presence of any particles;

　　(2) Smoothness: The HB interface is also sensitive to any type of morphology, which can create voids and ineffective bonds. The surface roughness threshold for dielectrics is generally considered to be 0.5nm, and the surface roughness threshold for copper pads is 1nm. To achieve this smoothness, CMP is required;

　　(3) Accuracy: The bonding accuracy limit can reach below 1 μm.

　　Advanced HBM/NAND will gradually adopt hybrid bonding comprehensively.

　　HBM3 generally uses thermocompression bonding technology, and major Korean manufacturers are expected to introduce hybrid bonding starting from HBM4. In HBM3, Micron and Samsung both use non-conductive film thermocompression bonding, while SK Hynix uses MR-MUF (bulk reflow soldering and molding filling) technology. Due to the higher requirements for stack height, contact points, and heat dissipation in HBM4+, the three major Korean manufacturers are expected to completely replace other bonding methods with hybrid bonding starting from HBM4.

　　In addition to HBM, Samsung's 10th generation V10 NAND will use the patented technology of YMTC, especially its hybrid bonding technology. YMTC started developing hybrid bonding technology in 2016 and launched Xtacking technology in 2018, followed by continuous technology iteration and upgrades. In 2025, YMTC has authorized Samsung to use its Xtacking architecture patent to manufacture V10 NAND (420-430-layer NAND).

　　Samsung's choice to cooperate with YMTC for V10 NAND is mainly due to the inability to circumvent YMTC's patent layout and the fact that YMTC's solution is more mature. (1) It is impossible to bypass the patents of YMTC, Xperi, and TSMC. YMTC's Xtacking patents exceed 1276, of which 56% involve 3D stacking processes (as of February 2025); (2) YMTC's solution is more mature, and we expect it to shorten the market launch cycle of Samsung's V10 NAND by 18-24 months, significantly alleviating the pressure from competitors' 300-layer+ NAND.

　　YMTC's Xtacking architecture is the optimal solution for 400-layer+ NAND, with hybrid bonding at its core.

　　Xtacking can significantly alleviate the chip area occupied by peripheral circuits in multi-stacked NAND, improving storage density. In traditional 3D NAND architecture, peripheral circuits account for about 20-30% of the chip area. As the number of stacking layers increases, the proportion of peripheral circuit area may exceed 50%, leading to a sharp decrease in chip storage density. Xtacking technology, by placing storage units and peripheral circuits on two separate wafers, can save the chip area occupied by peripheral circuits.

　　The core of Xtacking technology lies in processing storage units and peripheral circuits on two separate wafers, then bonding them together (hybrid bonding) through millions of vertical interconnect vias (VIA).

　　Xtacking can significantly improve chip transmission speed, storage density, and production efficiency: (1) High I/O speed, X-tacking technology increases the I/O speed of NAND to 3.0Gbps; (2) High storage density, by optimizing the layout of peripheral circuits, X-tacking technology significantly improves the storage density of the chip; (3) High production efficiency, the modular design allows storage units and peripheral circuits to be processed in parallel, greatly improving production efficiency.

　　The number of advanced chip die bonding steps is increasing, and the demand for hybrid bonding equipment will reach 2.8 billion euros in 2030.

　　With the increasing complexity of chips, the number of die bonding steps has surged, and the price of higher-performance bonding equipment is 3-5 times that of traditional flip-chip equipment. Taking AMD's EPYC processor as an example, from the first-generation EPYC processor launched in 2017 to the fourth-generation product released in 2023, (1) the number of bonding steps required in production has increased from 4 to over 50. (2) The bonding technology has iterated from flip-chip bonding to hybrid bonding + flip-chip bonding. The 8800 Ultra hybrid bonding equipment developed by BESI for this purpose is 3-5 times more expensive than flip-chip bonding machines.

　　The surge in AI computing demand coupled with the gradual adoption of hybrid bonding technology in memory devices, the total demand for hybrid bonding equipment will reach 2.8 billion euros, or approximately 20 billion RMB, in 2030. Besi predicts that hybrid bonding technology will be gradually introduced into memory production in 2025 and will be used in mobile phone processing chips around 2027. The cumulative demand for hybrid bonding equipment before 2030 is expected to exceed 1400 sets, corresponding to an equipment value of approximately 2.8 billion euros. The main suppliers of hybrid bonding equipment currently include EVG (Austria), SUSS (Germany), Besi (Netherlands), and ASMPT (Hong Kong).

　　Hybrid bonding equipment is still dominated by foreign companies, and domestic substitution is expected to accelerate.

　　The global market for hybrid bonding equipment is primarily dominated by international leading companies, with BESI being the leader in this field, holding a market share as high as 67%. Its equipment is widely used in 3D IC, MEMS, and advanced packaging, and it has a significant advantage in the high-end market. In addition, EVG of Austria and SUSS of Germany are also major suppliers of this equipment. At the same time, the domestic hybrid bonding equipment market is also gradually rising. Domestic companies such as TJC and Maiwei have also deployed hybrid bonding equipment. Domestic manufacturers are gradually breaking through key technologies and are expected to increase their market share in the next few years.

　　China's TJC, Maiwei, and Baoao Chemical (Xinhuilian) are actively deploying hybrid bonding equipment. (1) TJC has launched W2W bonding products (Dione 300) and D2W bonding surface pretreatment products (Pollux). Its W2W/D2W hybrid bonding surface pretreatment and bonding products have received repeat orders. (2) Maiwei is the first domestic company to achieve an accuracy of ±100nm in hybrid bonding equipment, and its next goal is ±50nm; benchmarking against international leaders EVG and Besi. (3) Baoao Chemical (Xinhuilian) has already shipped 2 D2W and W2W hybrid bonding equipment.

　　4 Advanced Packaging Wafer Thinning, Temporary Bonding & Debonding as Required Processes

　　Wafer-level stacking packaging technology creates a demand for ultra-thin wafers and temporary bonding processes

　　Wafer thinning technology has become a core process in advanced packaging, and the many advantages of ultra-thin wafers directly drive an increase in the number of 3D stacking layers. In some advanced packaging applications, it is necessary to thin the wafer to less than 10μm. ① Enhanced heat dissipation: Ultra-thin wafers can effectively reduce thermal resistance and improve the heat accumulation problem caused by multi-layer stacking of wafers in advanced packaging. ② Enhanced electrical performance: Using ultra-thin wafers shortens the interconnect length between components, thereby increasing signal transmission speed, reducing parasitic power consumption, and improving signal-to-noise ratio. ③ Improved integration: Using ultra-thin wafers in three-dimensional integrated silicon through-hole TSV technology can produce smaller pitch and higher density silicon through-holes while ensuring the aspect ratio. ④ Reduced cost: Subsequent processes such as etching, drilling, passivation, and plating on ultra-thin wafers can greatly increase processing speed and yield, while effectively reducing material costs.

　　Wafer thinning processes require the introduction of temporary bonding to provide mechanical support. When the silicon wafer is thinned to less than 100μm, residual stress is generated in the wafer during the process, the mechanical strength is reduced, and due to the influence of its own mass, it will exhibit significant flexibility and brittleness, easily warping, bending, or even breaking. Therefore, for ultra-thin wafers, it is necessary to use external support methods to protect them, facilitating subsequent processes on ultra-thin wafers and improving the yield, processing accuracy, and packaging accuracy in chip manufacturing, thus creating a demand for temporary bonding/debonding processes. Before back-end thinning, temporary bonding is used to transfer the wafer to a wafer carrier to provide strength support, and debonding is performed after completing back-end thinning and other back-end processes.

　　Temporary bonding processes can be divided into temporary thermocompression bonding and UV curing bonding

　　Temporary bonding generally uses two methods: temporary thermocompression bonding and UV curing. Temporary bonding first involves uniformly applying temporary bonding adhesive to the surface of the device wafer and carrier using spin coating or spraying, and then using thermocompression bonding or UV curing bonding to firmly bond the carrier and wafer. (1) Thermocompression bonding: In a high-temperature, vacuum bonding chamber, a certain force is applied to the device wafer and carrier stacked together to achieve a good bonding effect; (2) UV curing bonding: Ultraviolet light penetrates the carrier and irradiates the surface of the bonding adhesive, causing a reaction that bonds the carrier and device wafer together.

　　The compatibility and alignment accuracy of temporary bonding equipment constitute the core barriers

　　Temporary bonding equipment mainly consists of a control system, upper and lower wafer mechanisms, a spin coating worktable, a flipping manipulator, an alignment system, and a UV curing worktable. The control system controls the equipment's operating sequence; the upper and lower wafer mechanisms complete the loading/unloading of the wafer (and carrier); the spin coating worktable completes the coating of temporary bonding adhesive on the surface of the device wafer and carrier, and the uniformity and thickness of the temporary bonding adhesive will directly affect the effect of temporary bonding; the flipping manipulator controls the transfer and flipping of the wafer at different workstations; the alignment system aligns the carrier and the device wafer, and then uses a CCD imaging system and X, Y, θ directional movement mechanisms to achieve scanning alignment; after alignment, UV light is irradiated on the UV curing worktable while applying a certain pressure to complete the temporary bonding.

　　The core technological barriers and technical difficulties of temporary bonding equipment lie in multi-material/high and low temperature adaptability, high alignment accuracy, and mechanical stress control. ① Mechanical stress control: Preventing ultra-thin wafers from warping or cracking due to mechanical stress during processing. ② High-temperature adaptability: Temporary bonding materials usually need to be heated for curing or softening, and the equipment needs to be able to handle high-temperature processes. ③ High alignment accuracy: The wafer and carrier must be precisely aligned to prevent error accumulation in subsequent processes. The alignment accuracy requirements are very high when involving multi-level lithography processes, with the international advanced level being less than 50nm. ④ Multi-process compatibility: Temporary bonding equipment must be able to accommodate different process requirements, such as different bonding materials, different temperature requirements, and different wafer thicknesses.

　　Debonding process: Laser debonding can achieve high-density, large-size ultra-thin wafer separation

　　According to different debonding methods, debonding is mainly divided into four methods: mechanical peeling, wet chemical immersion, thermal sliding, and laser debonding. Mechanical debonding is to separate the carrier and the device wafer by tensile force, with a high fragmentation rate; chemical debonding is to dissolve the adhesive with a solvent, which is low in cost but low in efficiency and is not suitable for mass production; thermal sliding debonding is to soften the adhesive at high temperature and then separate the device wafer from the carrier, but the adhesive is easy to remain on the equipment platform, affecting subsequent product processes; laser debonding is to irradiate the adhesive layer with a laser through the glass, generating heat to decompose the adhesive or generate energy to break chemical bonds, which is the main debonding method currently used.

　　Laser debonding technology is expected to meet the requirements of high-density, large-size, and ultra-thin device wafer separation. Laser debonding can penetrate the transparent carrier and only ablate a few hundred nanometers of the response layer near the interface without affecting the device wafer. The carrier can be removed under a debonding force of less than 10N, greatly reducing the fragmentation rate of ultra-thin wafers. At the same time, the focal plane of the focused laser beam can be precisely controlled in the area of the response layer interface, ensuring that the laser beam selectively ablates only the photosensitive response layer, thereby reducing the risk of damage to the ultra-thin device and the carrier wafer.

　　Debonding Equipment: Balancing Bonding Stability and Debonding Cleanability

　　● Debonding equipment mainly consists of a control system, upper and lower wafer mechanisms, a laser debonding workstation, a flippable robotic arm, and a cleaning workstation. The control system controls the equipment's operating sequence; the upper and lower wafer mechanisms complete the loading/unloading of wafers (or carriers); the flippable robotic arm completes the transfer and flipping of wafers (or carriers) at different workstations; the cleaning workstation cleans the debonded device wafers and carriers, removing surface adhesive, after which the carriers can be used for the next round of temporary bonding. The laser debonding workstation is the core part of the bonding equipment.

　　● A balance needs to be struck between temporary bonding stability and the ease of cleaning residual adhesive after debonding. The other side of stable temporary bonding is that debonding and cleaning residual adhesive is more troublesome, requiring more time to remove the adhesive. Balancing bonding stability and the ease of cleaning residual adhesive after debonding requires more time to resolve.

　　● Optical debonding equipment may become the next direction to replace laser debonding equipment: Laser debonding processes require the addition of a laser-sensitive release layer as a temporary bonding material on the glass carrier, but cleaning the residual adhesive will damage the glass carrier. The biggest feature of optical debonding is that it no longer uses a laser release layer, but adds a permanent light-absorbing reaction layer (CLAL) to the glass carrier, eliminating the spin-coating process in laser debonding and eliminating the need for expensive IR or UV lasers. Instead, it uses a high-intensity flash lamp, converting light energy into heat to dissolve the bonding adhesive between the carrier and the wafer, ensuring debonding without residue. The advantages include high yield, low cost, no residue, and no spin-coating process.

　　The market space for temporary bonding and debonding equipment is approximately $100 million+, with concentrated leading companies.

　　● In 2020, the temporary bonding/debonding equipment market was valued at $113 million. According to YOLE data, the temporary bonding/debonding equipment market is expected to grow to $176 million by 2027 at a CAGR of 7%. Thin wafer temporary bonding is widely used in MEMS, advanced packaging, CMOS, etc., with MEMS being the largest market, accounting for approximately 35% in 2019, and advanced packaging being the second largest market, at approximately 31%. In the global thin wafer temporary bonding equipment consumption market, the sales volume in China accounts for the largest share, accounting for about one-third of the global market; Japan accounts for about 20%, and the rest is Europe and the United States.

　　● Foreign equipment suppliers are mainly EVG, SUSS, and TEL, while domestic companies such as Xinyuan Micro and Maiwei Co., Ltd. also have layouts.

　　High-density packaging technology achieves high-density integration and miniaturization of chips while reducing costs without requiring improvements in chip processes. This aligns with the trend of high-end chips evolving towards smaller sizes, higher performance, and lower power consumption.

　　5. Wide range of applications

　　In emerging fields such as 5G and the Internet of Things, the application of high-density packaging technology will be even more extensive, and will become one of the key technologies driving the development of these fields.

　　6. Diverse technologies

　　High-density packaging technologies include chip-scale packaging (CSP), ball grid array packaging (BGA), and flip-chip packaging (FlipChip). These technologies achieve high-density packaging by reducing package size and increasing pin density.