What is the estimated growth rate for the process diagnostics and control business in calendar 2021
de-long trends that will underpin secular industry growth.
As I've said before, digital transformation is built on silicon and broadens the drivers for semiconductor innovation. Demand for semiconductors is no longer about one or two killer applications, but rather an expansive, structural shift in the economy toward digitization and automation. Smart and connected devices at the edge not only consume more silicon. They are driving exponential growth in machine-generated data.
To make sense and create value from the vast volumes of data available, new AI computing approaches are needed fueling further demand for current and next-generation semiconductors. While global consumption of silicon is accelerating, adoption rates of new technology vary considerably by region. As we showed at our investor meeting, we estimate that by 2025, China will have only reached the same levels of silicon spend per capita the U.S. saw in 2015.
And India trails China by another eight to 10 years. Since the impact of digital transformation is so wide-reaching, national governments are increasingly recognizing the strategic importance of semiconductors. As government incentives become available in the U.S., Asia, and Europe, they can provide multi-year support as the industry moves from lean and just-in-time supply chains to more resilient, flexible, and secure approaches, including regionally distributed capacity. However, putting the right manufacturing infrastructure in place is only one piece of the puzzle.
Investment in innovation infrastructure, to lead in the development and commercialization of next-generation technologies, is even more critical to winning the future. Early access to superior semiconductor technologies, or what I refer to as winning the PPACt race, will determine the countries and companies that thrive and those that won't. At Applied, we have a strong point of view that the industry's future will not be like the past, and we have aligned our strategy and investments accordingly. Our strategy has three pillars.
First and foremost, we are focused on being the PPACt enablement company to provide the foundation for customers' power, performance, area, cost and time-to-market roadmaps. We have the broadest and most enabling portfolio of process technologies that we can co-optimize and combine in unique and highly enabling ways. Second, we are shifting more of our business to subscriptions as we believe this model provides significant benefits to customers and for us. We have already converted a meaningful portion of our installed base business to recurring revenues and we are starting to monetize new products and services using subscription approaches.
And, third, we continue to optimize our portfolio of businesses that serve adjacent markets, including display, to drive profitable growth and higher free cash flows. This strategy is yielding results and 2021 is shaping up to be a strong year of outperformance for Applied. Starting with our unit process tools, we are seeing a very strong demand for our leadership products. For example, taking the midpoint of our fourth-quarter guidance, both our epi and thermal businesses are on track to grow more than 70% this fiscal year, while CMP will grow more than 60% and implant more than 50%.
We're also seeing outperformance in our growth areas, especially process diagnostics and control, where we expect to grow more than 60% in calendar 2021. On top of this, we have strong momentum with our co-optimized and integrated solutions. By revenue, about 70% of the semiconductor products we sell today have already been co-optimized at some level. Co-optimization allows us to see and solve higher-value problems for customers, speed up technology transition to high-volume manufacturing, and make our solutions stickier.
Beyond co-optimization, our integrated materials solutions called IMS combine multiple processes with customized metrology and sensors in a single system typically under vacuum. Our latest IMS product, that lowers interconnect resistance by 50% in advanced foundry-logic, direc
de-long trends that will underpin secular industry growth.
As I've said before, digital transformation is built on silicon and broadens the drivers for semiconductor innovation. Demand for semiconductors is no longer about one or two killer applications, but rather an expansive, structural shift in the economy toward digitization and automation. Smart and connected devices at the edge not only consume more silicon. They are driving exponential growth in machine-generated data.
To make sense and create value from the vast volumes of data available, new AI computing approaches are needed fueling further demand for current and next-generation semiconductors. While global consumption of silicon is accelerating, adoption rates of new technology vary considerably by region. As we showed at our investor meeting, we estimate that by 2025, China will have only reached the same levels of silicon spend per capita the U.S. saw in 2015.
And India trails China by another eight to 10 years. Since the impact of digital transformation is so wide-reaching, national governments are increasingly recognizing the strategic importance of semiconductors. As government incentives become available in the U.S., Asia, and Europe, they can provide multi-year support as the industry moves from lean and just-in-time supply chains to more resilient, flexible, and secure approaches, including regionally distributed capacity. However, putting the right manufacturing infrastructure in place is only one piece of the puzzle.
Investment in innovation infrastructure, to lead in the development and commercialization of next-generation technologies, is even more critical to winning the future. Early access to superior semiconductor technologies, or what I refer to as winning the PPACt race, will determine the countries and companies that thrive and those that won't. At Applied, we have a strong point of view that the industry's future will not be like the past, and we have aligned our strategy and investments accordingly. Our strategy has three pillars.
First and foremost, we are focused on being the PPACt enablement company to provide the foundation for customers' power, performance, area, cost and time-to-market roadmaps. We have the broadest and most enabling portfolio of process technologies that we can co-optimize and combine in unique and highly enabling ways. Second, we are shifting more of our business to subscriptions as we believe this model provides significant benefits to customers and for us. We have already converted a meaningful portion of our installed base business to recurring revenues and we are starting to monetize new products and services using subscription approaches.
 And, third, we continue to optimize our portfolio of businesses that serve adjacent markets, including display, to drive profitable growth and higher free cash flows. This strategy is yielding results and 2021 is shaping up to be a strong year of outperformance for Applied. Starting with our unit process tools, we are seeing a very strong demand for our leadership products. For example, taking the midpoint of our fourth-quarter guidance, both our epi and thermal businesses are on track to grow more than 70% this fiscal year, while CMP will grow more than 60% and implant more than 50%.
We're also seeing outperformance in our growth areas, especially process diagnostics and control, where we expect to grow more than 60% in calendar 2021. On top of this, we have strong momentum with our co-optimized and integrated solutions. By revenue, about 70% of the semiconductor products we sell today have already been co-optimized at some level. Co-optimization allows us to see and solve higher-value problems for customers, speed up technology transition to high-volume manufacturing, and make our solutions stickier.
Beyond co-optimization, our integrated materials solutions called IMS combine multiple processes with customized metrology and sensors in a single system typically under vacuum. Our latest IMS product, that lowers interconnect resistance by 50% in advanced foundry-logic, direc