Method and apparatus comprising a semiconductor device and test apparatus

A method of testing a semiconductor device, the method comprising:

• providing a semiconductor device comprising an integrated circuit and a plurality of external radiating elements at a surface of the device, the radiating elements including at least one transmit element and at least one receive element;
• providing a test apparatus for testing the semiconductor device, the test apparatus comprising:
• a surface for placing against said surface of the device;
• and
• at least one waveguide, wherein each waveguide extends through the test apparatus for routing electromagnetic radiation transmitted by one of said transmit elements of the device to one of the receive elements of the device,
• wherein each waveguide comprises a plurality of waveguide openings for coupling electromagnetically to corresponding radiating elements of the plurality of radiating elements located at the surface of the device,
• wherein a spacing between the waveguide openings of each waveguide of the test apparatus is larger than, or smaller than a spacing between the corresponding radiating elements of the device, and
• transmitting electromagnetic radiation from at least one said transmit element to at least one said receive element via at least one waveguide of the test apparatus.