Back again, eh? Well, I'm glad to see you're enjoying our little rundown of easy-to-invest-in German equities. So far, we've covered Germany's American Depositary Receipts (ADR) representing the insurance, banking, utilities, chemical, and industrial machinery sectors.

With those slow-growth industries out of the way, it's time to step up the pace a bit as we begin to examine Germany's high-tech sectors.

Today, we'll look at four Teutonic semiconductor companies whose shares can be purchased with a single mouse click. As always, I'll preface each write-up with a synopsis of the "Level" of ADR on offer, and the ratio of underlying shares to each ADR trading on the NYSE.

Without further ado, then, it's once again time to ...

Get to know a country

Infineon (NYSE:IFX)
(Level III ADR) 1 ADR = 1 Common Share

The youngest company of the bunch, Infineon was born in 1999. It produces semiconductors for use in cars, communications (e.g. DSL and cell phones), and computers (laptops, desktops, and servers). But the company has gained its most recent notoriety for making the graphics chips that power Motley Fool Inside Value pick Microsoft's new Xbox 360 gaming console -- or, according to recent press reports, for not making enough of them, which allegedly caused last Christmas's Xbox shortage.

The company's closest publicly traded competitor is Switzerland's STMicroelectronics (NYSE:STM), but Infineon's products also compete with such names as AMD. The major difference between Infineon and its competitors: They're profitable. Since its founding, Infineon has only generated positive free cash flow in two years: 2000 and 2004. It started off the current fiscal year by burning more than 300 million euro worth of cash, and looks likely to burn more as the year progresses.

Sorry, Infineon. No medal for you.

Aixtron (NASDAQ:AIXG)
(Level II ADR) 1 ADR = 1 Common Share

Aixtron isn't a semiconductor company per se. Rather, it provides equipment to the chipmakers -- selling picks and shovels to the Silicon Rush, if you will.

Like Infineon (an Aixtron customer, along with companies such as NEC, Samsung, and Seagate), Aixtron is a money-loser this year, with 10 million euro in accounting losses already racked up. With only one more quarter to report for the year, Aixtron's unlikely to turn it around. Historically, it's managed to generate accounting profits in three of the past five years. On a cash profits basis, however, the company generated net negative free cash flow of 17.8 million euro over the same time period, so those accounting profits may not be all they're cracked up to be.

Even angels fear to tread here. Fools shouldn't rush in.

Dialog Semiconductor (NASDAQ:DLGS)
(Level II ADR) 1 ADR = 1 Common Share

Why manufacture chips when you can just design them and let someone else worry about the factories? That's the path little Dialog Semiconductor has chosen, following in the footsteps of such "fabless" chipmakers as Motley Fool Stock Advisor picks NVIDIA (NASDAQ:NVDA) and ARM Holdings (NASDAQ:ARMHY).

As originally envisioned, fabless chip-making was supposed to minimize the cost of doing business, yielding boffo profit margins. So far, the theory has proven out at NVIDIA and ARM. No such luck for Dialog, however, which hasn't earned a profit since the year 2000. That's hardly the performance of a medal contender.

Epcos (NYSE:EPC)
(Level III ADR) 1 ADR = 1 Common Share

Epcos is in electronics -- sort of a similar industry to semiconductors, though the company doesn't make or design them or any related equipment -- so it fits better here than among the health care, chemicals, insurance, or other companies we examine elsewhere in this series.

Not that it really makes much difference where we put Epcos; the company would roll to the bottom of pretty much any heap we toss it onto. Epcos, you see, operates in the commodity industry of producing electronics components -- capacitors, thermistors, surge arrestors, and similar electronic widgets and thingamajigs. Basically, stuff that you'd expect to be produced cheaply and in quantity in China or Taiwan -- not Germany.

Epcos might have been a fine company if Southeast Asia didn't exist. But in the real world, it loses money as often as it earns it -- and it loses more money in its bad years than it earns in its good ones.

Who gets the gold?
To paraphrase comedian and New York Post columnist Joey Adams: "The difference between the Olympics and investing is that, in the Olympics, someone has to win." In today's review of our four German semiconductor/electronics companies, no one does.

Fools can find much better prospects for their investing dollars right here at home in the USA, by choosing AMD over Infineon, for example. Or by avoiding Dialog, which hasn't managed to make the fabless manufacturing model work for it, and instead buying more successful rivals NVIDIA or ARM Holdings.

For more winning stock picks from David and Tom Gardner, sign up today for a free 30-day trial to Motley Fool Stock Advisor .

Fool contributor Rich Smith does not own shares of any company named above.