i would suggest that you read through this thread. This topic has been discussed many times already
Chinese semiconductor thread II
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Thickness Control and Thermal Stability of Large‐Diameter Mo/Si Multilayer Films for Extreme Ultraviolet Source.
Abstract
Mo/Si multilayer films exhibit the highest measured reflectivity in the extreme ultraviolet (EUV) region, and their combination with an EUV light source enables EUV lithography. In practical applications of EUV light sources, Mo/Si multilayer mirrors are always curved and have large diameters. The angle of the incident light constantly changes along the curved surface. To match the multilayer peak reflectivity with the angle of the incident light, the period thickness of the Mo/Si multilayer films must be distributed in a transverse gradient along the surface to ensure high EUV reflectivity. Simultaneously, given that the mirror is close to the light source, the multilayer films must operate in an environment with a high thermal load. Higher temperatures can increase the formation of silicide at the multilayer interface, causing the optical performance to decrease. Therefore, Mo/Si multilayer films for EUV light sources also have high thermal stability requirements. To address these issues, we use a shadow mask to correct the periodic thicknesses of the multilayer films at different positions on a curved substrate with a diameter of 300 mm. Carbon is selected as the diffusion barrier material to investigate the influence of C-barrier layer on the thermal stability of Mo/Si multilayer.
Results and Discussions
In the study involving film thickness control, the XRR measurement results show that the samples at different positions exhibit similar layer structures (Fig.4). Atom force microscope (AFM) tests are performed on Mo/Si multilayer films deposited at four different positions on the entire mirror. The surface roughness values of the four samples are 0.128, 0.123, 0.124, and 0.118 nm. The morphologies of the four samples are similar (Fig.5). Using the shadow mask, the deviation of the period thickness on the 300-mm diameter curved substrate is controlled within ±0.45% of the expected period thickness (Fig.6).
In the study involving thermal stability, after annealing at 300 ℃ for 2h, the period thickness of Mo/Si multilayer films changes from 6.99 nm to 6.69 nm, the period thickness of Mo/Si/C multilayer films changes from 6.96 nm to 6.91 nm, and the period thickness of Mo/C/Si/C multilayer films is almost same before and after the annealing, which changes from 6.97 nm to 7.00 nm. The C barrier layer can effectively mitigate the interdiffusion at the interface of the Mo and Si layers, which improves the thermal stability of the multilayer films (Fig.7). The EUV reflectivity of Mo/Si multilayer films decreases from 64.4% to 55.4% after annealing at 300 ℃ for 2 h, and the central wavelength has a shift of 0.51 nm. The EUV reflectivity of the Mo/Si/C multilayer films decreases from 66.4% to 59.6% after annealing, and the center wavelength shifts by 0.11 nm. The reflectivity of Mo/C/Si/C multilayer films decreases by 1.8% after annealing, and central wavelength shifts by 0.02 nm (Fig.8 and Table 2). Furthermore, the EUV reflectivity results show that the C barrier inserted at both interfaces of the Mo/Si multilayer films can significantly improve thermal stability.
Mo/Si multilayer films exhibit the highest measured reflectivity in the extreme ultraviolet (EUV) region, and their combination with an EUV light source enables EUV lithography. In practical applications of EUV light sources, Mo/Si multilayer mirrors are always curved and have large diameters. The angle of the incident light constantly changes along the curved surface. To match the multilayer peak reflectivity with the angle of the incident light, the period thickness of the Mo/Si multilayer films must be distributed in a transverse gradient along the surface to ensure high EUV reflectivity. Simultaneously, given that the mirror is close to the light source, the multilayer films must operate in an environment with a high thermal load. Higher temperatures can increase the formation of silicide at the multilayer interface, causing the optical performance to decrease. Therefore, Mo/Si multilayer films for EUV light sources also have high thermal stability requirements. To address these issues, we use a shadow mask to correct the periodic thicknesses of the multilayer films at different positions on a curved substrate with a diameter of 300 mm. Carbon is selected as the diffusion barrier material to investigate the influence of C-barrier layer on the thermal stability of Mo/Si multilayer.
Results and Discussions
In the study involving film thickness control, the XRR measurement results show that the samples at different positions exhibit similar layer structures (Fig.4). Atom force microscope (AFM) tests are performed on Mo/Si multilayer films deposited at four different positions on the entire mirror. The surface roughness values of the four samples are 0.128, 0.123, 0.124, and 0.118 nm. The morphologies of the four samples are similar (Fig.5). Using the shadow mask, the deviation of the period thickness on the 300-mm diameter curved substrate is controlled within ±0.45% of the expected period thickness (Fig.6).
In the study involving thermal stability, after annealing at 300 ℃ for 2h, the period thickness of Mo/Si multilayer films changes from 6.99 nm to 6.69 nm, the period thickness of Mo/Si/C multilayer films changes from 6.96 nm to 6.91 nm, and the period thickness of Mo/C/Si/C multilayer films is almost same before and after the annealing, which changes from 6.97 nm to 7.00 nm. The C barrier layer can effectively mitigate the interdiffusion at the interface of the Mo and Si layers, which improves the thermal stability of the multilayer films (Fig.7). The EUV reflectivity of Mo/Si multilayer films decreases from 64.4% to 55.4% after annealing at 300 ℃ for 2 h, and the central wavelength has a shift of 0.51 nm. The EUV reflectivity of the Mo/Si/C multilayer films decreases from 66.4% to 59.6% after annealing, and the center wavelength shifts by 0.11 nm. The reflectivity of Mo/C/Si/C multilayer films decreases by 1.8% after annealing, and central wavelength shifts by 0.02 nm (Fig.8 and Table 2). Furthermore, the EUV reflectivity results show that the C barrier inserted at both interfaces of the Mo/Si multilayer films can significantly improve thermal stability.
Read the post I made. That isn't true. Those charts those guys made are comparing the whole yearly revenue of Qualcomm and MediaTek with a single quarter of HiSilicon revenue. They are blatant lies.
From listening to SMIC earnings call today
They definitely talked about need to build up capacity and the rationale for capex as being good for long term future of the company.
Talked about some customers gaining market share and needing rapid stocking up (interesting!!!)
7% increase in 8-inch equivalent shipment
3% decrease in ASP due to product mix
talked about focus on CIS, DDIC, High voltage, nor flash, nand flash, NVM, BCD platforms
While maintaining market share for medium to large screen, it has gained market share in small screens for smart phones & other consumer electronics
It has launched it's first 28nm DDIC for AMOLED screen
Received certification for CNSA for introduction of auto chip platform
12-inch product is "fully booked" as in it is facing bottleneck. Not seeing price declines there
pricing weakness is in 8-inch due to competition
SMIC getting increased market share in Chinese smartphones supply chain
28nm platform - need continued R&D
SMIC already produces what is referred to externally as 22nm (cut down version of 28nm)
SMIC produces this for DDIC, CIS, ISP, MCU & more (nand flash @ 24nm is a special version of 28nm product)
SMIC needs to continue to build the capacity here for its customers
Benefits from China for China movement
Talks about the role of running AI models on phones as a driver for chip advancements
continued to announce $7.5B capex this year, but who knows (they already spent $2.2B in Q1)
They definitely talked about need to build up capacity and the rationale for capex as being good for long term future of the company.
Talked about some customers gaining market share and needing rapid stocking up (interesting!!!)
7% increase in 8-inch equivalent shipment
3% decrease in ASP due to product mix
talked about focus on CIS, DDIC, High voltage, nor flash, nand flash, NVM, BCD platforms
While maintaining market share for medium to large screen, it has gained market share in small screens for smart phones & other consumer electronics
It has launched it's first 28nm DDIC for AMOLED screen
Received certification for CNSA for introduction of auto chip platform
12-inch product is "fully booked" as in it is facing bottleneck. Not seeing price declines there
pricing weakness is in 8-inch due to competition
SMIC getting increased market share in Chinese smartphones supply chain
28nm platform - need continued R&D
SMIC already produces what is referred to externally as 22nm (cut down version of 28nm)
SMIC produces this for DDIC, CIS, ISP, MCU & more (nand flash @ 24nm is a special version of 28nm product)
SMIC needs to continue to build the capacity here for its customers
Benefits from China for China movement
Talks about the role of running AI models on phones as a driver for chip advancements
continued to announce $7.5B capex this year, but who knows (they already spent $2.2B in Q1)
I question their Hisilicon revenues if they got the other ones wrong
SMIC capex + Depreciation & amortization since Q1 of last year. Huge jump here in capex and depreciation. Expect Depreciation to really weigh down their margins in the coming couple of years since they are spending more on capex than revenue they are taking int
It is really tough for SMIC. They are competing against established companies, those companies already have depreciated their equipment, and they started their fabs a long time ago when the processes were closer to leading edge and you could get more revenue per wafer. There is a huge price differential between leading edge processes and legacy ones. Semi tools also typically do not go down in price. Even second hand tools are regularly sold at the price of new ones. At best it could be that more modern tools have a higher production rate. But typically even older machines can be upgraded. Then again TSMC also started this way.
It is also possible US led sanctions could further cripple SMIC's production and damage its economic capability to pay back this investment. But I am fairly certain if this happened then the Chinese government would step in to financially rescue the company. It is that important. It might even be a good thing in the long run because it will force them to use Chinese equipment and materials. This will mean increased investments in both sectors.
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Sanctions are totally working. If we tighten it just a tad bit more it will be the end of Chinese semi industry as we know it.
Oh, it has become an honor to be on the BIS list now. The company my friend works for used to be an ordinary company without much reputation, but since being on the BIS list last year, they have welcomed many new customers. . People seem to think that the U.S. sanctions list provides an endorsement of the company's technical capabilities.