The market for advanced computer chips continues to grow not only in value, but in importance. The pandemic was proof of that, with production of many consumer products, from game consoles to new cars, disrupted because manufacturers couldn't get their hands on critical semiconductor components. 

The industry was worth $452 billion in 2021, and over the next 10 years it could expand to over $1 trillion in annual value. There are plenty of opportunities for investors to benefit from that growth. Here are two semiconductor-service companies that can be bought right now at a discount to their all-time highs amid the broader sell-off in the tech sector

1. Axcelis Technologies

Axcelis Technologies (ACLS 0.68%) doesn't produce any semiconductors itself. Instead, it sells ion implantation equipment to some of the world's largest chipmakers, playing a critical role in the fabrication process. Its Purion series of machines are used in the manufacturing of chips for a variety of different applications, from cars to mobile devices.

The company is in the middle of the busiest period in its history as producers seek to expand their capacity to catch up with supply shortages, as well as meet future demand driven by more consumer products adopting digital capabilities. As a result, Axcelis' order backlog is at its highest on record, which bodes well for its future revenue and earnings potential.

The company says it's on track to generate $850 million in revenue during 2022, which is a full year ahead of schedule. As an added bonus, Axcelis is highly profitable, with $2.88 in earnings per share in 2021, which could grow by 53% to $4.41 this year, according to analysts' estimates. That gives the stock a very attractive forward price-to-earnings ratio of 11.5, which is a 45% discount to the Nasdaq-100 technology index's forward multiple of 20.9. 

But the stock wasn't always this cheap; it's currently down 39% from its all-time high as investors have shunned growth stocks in the face of high inflation and rising interest rates. However, it's important to take a long-term view with Axcelis given the projected growth of the chip sector over the next decade. It continues to innovate, and has highlighted a number of equipment shipments this year to both new and existing customers.

2. Cohu

Like Axcelis, Cohu (COHU 0.14%) provides critical equipment and services to chipmakers around the world. It focuses on testing and handling, which ensures the end user receives a product that performs as intended and is free from defects.

Cohu integrates artificial intelligence (AI) into its defect detection technology, which can distinguish between harmless cosmetic faults and true structural issues as small as five micrometers. For context, a strand of human hair is about 70 micrometers in thickness. Cohu's process is a true game changer, especially considering its AI continues to learn and improve. 

Cohu's semiconductor-producing customers address a number of different areas, but the company shifted its focus to the automotive segment during the pandemic to help alleviate crippling chip shortages in that industry. It made up the majority of Cohu's revenue during 2021, but the business has since pivoted yet again, with the mobility segment now holding that title, accounting for 16% of revenue in Q1 2022. Mobility can include everything from 5G connectivity to mobile displays and even chips used for virtual reality video. 

It highlights Cohu's adaptability in what is a very fast-paced industry. The company generated revenue of $887 million in 2021, representing 39% growth compared to 2020. Analysts' estimates suggest revenue will be stable in 2022 and 2023 as Cohu consolidates one of the strongest periods in its history. But the company recently revised its midterm forecasts higher, telling investors its revenue and earnings per share will average $1 billion and $4.00, respectively, each year over the next three-to-five years.

Cohu stock is down 46% from its all-time high, which might be a big opportunity to build a position. The company is due to report its Q2 2022 earnings results on July 28 and a recent business update suggests it will beat expectations on revenue. It's not surprising given its first-quarter report revealed a record order backlog.

But the focus should remain on the long term, because this $1.3 billion company has plenty of room to grow alongside the semiconductor industry.