Investors are in the middle of digesting one of the most important earnings seasons in recent memory and trying to gauge how consumers and businesses are coping with rapidly rising interest rates and multi-decade-high inflation. 

The semiconductor industry is a good bellwether for the health of the broader economy because advanced computer chips are finding their way into an increasing number of products and services. If the chip sector does well, it's a hint that consumers and businesses are still spending money. 

Cohu (COHU 1.17%), MKS Instruments (MKSI -1.14%), and Axcelis Technologies (ACLS -0.86%) have all reported their financial results for the second quarter of 2022 in the past 30 days, and all three stocks have recorded strong gains since. Here's why it's not too late to buy in. 

1. Cohu: Up 14% in the past month

Cohu is a manufacturer of testing and handling equipment for semiconductor producers in a variety of categories, whether they make chips for the automotive sector, the 5G telecommunications sector, or general consumer electronics. This equipment is critical for a few reasons, but most importantly to ensure hardware defects are detected before final products reach end users.

Cohu applies advanced technology like artificial intelligence to identify defects as small as five micrometers, and it can also determine whether cracks or irregularities are cosmetic (harmless) or structural. One of the company's inspection systems, called Neon, can handle fragile semiconductors as small as 0.2 millimeters in size, which are often found in cars and mobile handsets.

The company had a blockbuster year in 2021, generating a record-high $887 million in revenue as the chip sector benefited from soaring demand and limited supply. Those tailwinds have faded so far during 2022, and in the second quarter, Cohu's revenue result of $217 million represented an 11% dip compared to the same period last year.

But the company reiterated its commitment to its three- to five-year goal of delivering $1 billion in annual sales on average, plus $4 in annual earnings per share. That might be the best part about Cohu -- it's highly profitable. Based on its $2.89 in non-GAAP trailing 12-month EPS, Cohu stock trades at a price-to-earnings multiple of 10.4. That means it's about 49% cheaper than the broader chip sector right now, represented by the iShares Semiconductor ETF (SOXX -0.10%).

Cohu is working toward lofty financial goals and its stock is cheap. That's usually a recipe for gains, especially over the long term. 

2. MKS Instruments: Up 17% in the past month

MKS Instruments has arguably the widest reach of any chip stock on the market. The company has been in business for more than 60 years, and it makes one remarkable claim: It touches every single semiconductor produced globally through its variety of products and services.

MKS Instruments supports chip makers through all stages of the manufacturing process and helps them to overcome the challenges presented by modern-day hardware. As consumer devices become smaller and more portable, the semiconductors that power them also need to shrink in size while maintaining the same, or more, processing power. That calls for innovative solutions, which can include new components and raw materials.

Like many companies over the last two years, MKS Instruments continues to struggle with supply chain disruptions relating to the pandemic. In the second quarter of 2022, it generated revenue of $765 million, which was just 2% higher than its year-ago result. However, its semiconductor segment specifically, which represented two-thirds of the company's total sales, grew by a far stronger 19%.

There's a quarterly dividend of $0.22 per share up for grabs in this stock, which equates to an annual yield of 0.74%. That might not sound like a blockbuster return, but there's also an opportunity for MKS Instruments' stock price to build upon its 17% gain over the last month.

It trades at a price-to-earnings multiple of 10.5 right now, which, like Cohu stock, is much cheaper than the iShares Semiconductor ETF, which trades at a multiple of 20.6.

3. Axcelis Technologies: Up 35% in the past month

The star performer of this bunch is Axcelis Technologies. After posting record financial results in 2021, the company followed up with a stellar performance so far in 2022. Not only is Axcelis stock up 35% in the last month, but it's also flat for the year -- which highlights its strength compared to the Nasdaq-100 technology index, which continues to swing in and out of bear market territory

Axcelis manufactures ion implantation equipment for the world's top chip makers, which is essential to the fabrication process. The company has made a series of announcements this year informing investors of high-profile shipments of its products to both new and existing customers across a broad spectrum of production purposes, from memory chips to processors.

In the second quarter of 2022, Axcelis grew its revenue by 50% to $221.1 million, and its earnings per share by a whopping 140% to $1.32. On top of that, the company has the largest backlog of orders in its history right now, totaling $869 million, so there could be further strength coming in the back half of this year.

As a result, Axcelis lifted its 2022 full-year revenue guidance higher from $850 million to $875 million -- and if the company does exceed the $850 million mark in 2022, it will be an entire year ahead of schedule.

Axcelis is also in the process of returning $100 million to shareholders through a share buyback program, following on from the $75 million that has already been deployed since 2019. Despite all of these positives, investors can still pick up Axcelis stock right now at a price-to-earnings multiple of 17, a full 17% cheaper than the iShares Semiconductor ETF.