Photolithography

The word lithography comes from the Greek lithos, meaning stones, and graphia, meaning to write. It means quite literally writing on stones. In the case of semiconductor lithography (also called photolithography) our stones are silicon wafers and our patterns are written with a light sensitive polymer called a photoresist. To build the complex structures that make up a transistor and the many wires that connect the millions of transistors of a circuit, lithography and etch pattern transfer steps are repeated at least 10 times, but more typically are done 20 to 30 times to make one circuit. Each pattern being printed on the wafer is aligned to the previously formed patterns and slowly the conductors, insulators, and selectively doped regions are built up to form the final device.[1]

The steps used in photolithography is well described at following figures. [2]

Intel has this nice simple way of description for the photolithography process in video. 

SOURCE: INTEL

There are several companies using the photolithography process to produce chips. The US, South of Korea, and Taiwan are the top 3 producers which compete each other every year to be the biggest market share in the world. However, recently companies from China are also catching up. 

Based on investopedia [3], below companies are the top 10 in sales in year 2016:

1. INTEL [USA]- Sales: $56.31 billion
2. Samsung [KR]- Sales: $43.54 billion
3. TSMC [TWN] - Sales: $29.32 billion
4. Qualcomm [USA]- Sales: $15.44 billion
5. Broadcom [USA]- Sales: $15.33 billion
6. SK Hynix [KR] - Sales: $14.23 billion
7. Micron Technology [USA]- Sales: $12.84 billion
8. Texas Instruments [USA]- Sales: $12.35 billion
9. Toshiba [JPN]- Sales: $10.92 billion
10. NXP [NL] - Sales: $9.5 billion

While for photolithography equipment manufacturer itself, only 3 equipment suppliers are considered to be the top players in the industry and ASML has the biggest market shares for the DUV (Krf & Arf) and immersion type, with i-line as exception. For the i-line type of equipment, in 2011, CANON held the market shares of 52.9%, NIKON held a 40%, and ASML held only 7.7%. [4]

1. ASML [NL] 
2. CANON [JPN] 
3. NIKON [JPN] 

To understand more on photolithography's equipment classification, below picture shows a good comparison of how the equipment could perform in term of the overlay versus the exposure beam wavelength. [5]

Currently, the equipment suppliers are competing very hard to come up with solution of below 10nm overlay, solutions offered by each manufacturer is as following:

• ASML with the EUV
• Nikon with the Immersion DUV with multipatterning
• Canon with the Nanoimprint Lithography (NIL)

None of them has finished on developing this current edge technology. The winner of this competition will bring them to be next biggest market share in this particular node. 

Source:

[1] http://www.lithoguru.com/scientist/lithobasics.html

[2] https://cleanroom.soe.ucsc.edu/lithography

[3] http://www.investopedia.com/articles/markets/012216/worlds-top-10-semiconductor-companies-tsmintc.asp

[4] http://www.siliconsemiconductor.net/article/74993-Can-Nikon-or-Canon-Ever-Catch-ASML-in-the-Lithography-Market.php

[5] https://seekingalpha.com/article/3980332-can-anyone-beat-asml-sub-10nm-features-maybe