High Temperature Ferromagnetism with a Giant Magnetic Moment in Transparent Co-doped<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:msub><mml:mrow><mml:mi mathvariant="normal">S</mml:mi><mml:mi mathvariant="normal">n</mml:mi><mml:mi mathvariant="normal">O</mml:mi></mml:mrow><mml:mrow><mml:mn>2</mml:mn><mml:mo>−</mml:mo><mml:mi>δ</mml:mi></mml:mrow></mml:msub></mml:math>

The occurrence of room temperature ferromagnetism is demonstrated in pulsed laser deposited thin films of Sn(1-x)Co(x)O(2-delta) (x<0.3). Interestingly, films of Sn(0.95)Co(0.05)O(2-delta) grown on R-plane sapphire not only exhibit ferromagnetism with a Curie temperature close to 650 K, but also a giant magnetic moment of 7.5+/-0.5 micro(B)/Co, not yet reported in any diluted magnetic semiconductor system. The films are semiconducting and optically highly transparent.