Solar thin-film maker Energy Conversion Devices (ECD), which has factories in Michigan, USA, Canada and Mexico, has suspended manufacturing and will furlough 400 workers.

The Michigan-based company has said it needs to stop production because it has made more solar panels than it can sell. The company opened its plant in Ontario, Canada in early 2011, hoping to take advantage of the regional market’s generous government subsidies. However, it has admitted struggling to grow and make money.

According to reports, the ECD is not the only one solar panel maker facing difficulties. Some manufactures have filed for bankruptcy (Solyndra, SpectraWatt, Evergreen Solar), while others have closed factories or reduced production at existing factories.

First Solar started building a factory in Vietnam earlier this year, but it has been reported that the company has put that plan on hold because it, too, needs to cut costs.

Suntech Power, the largest silicon solar panel maker, also recently announced that it would not expand manufacturing in 2012.