It was facing a broad slowdown in demand in 2015 when Sanâan Optoelectronics, based in the eastern Chinese city of Xiamen, canceled a large order at the last minute.
The decision sent Aixtronâs share price crashing. By May of this year, it had agreed to sell itself to a Chinese investment fund, Fujian Grand Chip.
Yet in a twist that shows the conflicting interests that can lurk behind Chinese deals, Sanâan has a number of connections to Fujian Grand Chip, including a common investor and an existing financial relationship.
Fujian Grand Chip is 51 percent controlled by Liu Zhendong, a businessman the Mercator Institute said most likely had government connections but was otherwise hard to track. The rest is held by Xiamen Bohao, a local government investment fund that itself has links to Sanâan.
A financial filing showed that at the end of 2014, Sanâan owed Bohao 300 million renminbi, now worth about $ 45 million. The following year, another filing showed Bohao owed Sanâan 240 million renminbi. While there is no explanation given for the fund flows, they appear to be related to financing provided to Sanâan by Bohao.
There are other links as well. Another state-run investment firm based in Xiamen holds stakes in both companies. And a broader national investment fund is providing a loan facility, through a subsidiary, for the takeover of Aixtron while holding a stake in Sanâan.
Just three days after the Aixtron bid was announced, a new company was registered at an address in Quanzhou along the Taiwan Strait. Sanâan was an investor in the company, and the address was the same as that listed by Fujian Grand Chip in its Aixtron offer.
The connections do not necessarily indicate wrongdoing. Still, they raise questions about the independence of Chinese companies that have been on a global high-tech spending binge.
âIt is the goal of Chinese outbound industrial policy programs to replace foreign technology leaders in the medium term â not just in China but also in global export markets,â Mr. Heilmann said.
He echoed the complaints of American and European officials, who say that while Chinese companies â including those backed by the state â are able to mount takeover bids for companies in the West, the opposite is not typically allowed within China.
The German economics ministry declined to comment on the Aixtron takeover. Fujian Grand Chip, Bohao and Mr. Liu declined to comment. Sanâan did not respond to a request for comment, but in a statement, Aixtron said Sanâan canceled its order because its âspecific qualification requirements were not achieved.â
In an August conference call with analysts, Aixtronâs chief executive, Martin Goetzeler, said there no was current investment link between Sanâan and Fujian Grand Chip, a relationship that was first reported in the German magazine Capital.
Bids for companies like Aixtron reflect a shift in Chinese investment patterns that goes back a number of years.
Chinese companies bearing checkbooks have generally been welcomed in Europe. They have provided a source of fresh capital for ailing European enterprises, like the Swedish carmaker Volvo, the Italian tire maker Pirelli, the French resort operator Club Med, and the port in Piraeus, Greece.
But deals over the past two years â which last year hit a record 20 billion euros, or $ 22.4 billion, according to a survey by Rhodium Group and the Mercator Institute â have begun targeting leading-edge companies with crucial technologies and iconic brand names.
Anxieties are perhaps most acute in Germany, which has had Aixtron and the well-known robotics company Kuka â whose technology is ubiquitous in German car factories â both go to Chinese bidders this year. Largely because of those two deals, Germany has become the largest recipient of Chinese investment in Europe thus far in 2016, according to the Mercator Institute.
In the United States, a number of Chinese bids for chip companies have been undone by regulatory concerns. Regulators thwarted an overture by Sanâan for an American semiconductor company, and the Treasury Departmentâs Committee on Foreign Investment in the United States is reviewing the Aixtron bid.
By contrast, European laws give politicians few avenues to block acquisitions, though that has not stopped them from trying.
President FranÃ§ois Hollande of France has warned the Chinese hotel group Jin Jiang against trying to acquire a majority in the French hotel chain Accor. And last month, Prime Minister Theresa May of Britain delayed approval of a nuclear power plant because of security concerns about Chinese companies involved. (It has since been given the green light.)
In Germany, the takeover of Kuka â frequently cited by politicians as emblematic of the countryâs future economic development â has drawn particular attention. The economics ministry examined the takeover of the company by Midea Group in China, which already owns 95 percent of Kuka shares, but eventually decided the deal did not meet the strict criteria for a formal review.
Beyond politics, concerns also surround the origin of the money supporting Chinese bids.
The Aixtron case, in particular, shows how difficult that can be.
Ultimately both Sanâan, the customer, and Fujian Grand Chip, the buyer, are recipients of government funds earmarked to help China build out its semiconductor capabilities. While itâs not clear whether the two coordinated in any way, they are a product of a new approach Beijing has taken to develop its semiconductor industry.
Previously, Chinaâs government would dole out funds to several well-known state-owned companies. Now those funds are being distributed through national and local investment funds, which give them out to, and through, smaller companies like Bohao and Sanâan.
German companies have so far managed to stay ahead of China and other competitors in quality and technology, but there are growing concerns that Chinese companies are catching up.
âA lot of people in Germany have massive concerns about Chinese companies taking over leading tech companies,â said Daniel Bauer, a spokesman for SdK, a German investor-protection group. âPeople fear that foreign investors will just transfer the know-how and have no interest in keeping the facilities.â