Internet Explorer versions 7, 8, and 9 accept the @ font-face only if the font is EOT.
You can find any converter online that this problem is solved.
You can check the compatibility in Can I Use: Font Face
You can convert your fonts to EOT directly from the Font Squirrel .
Safari, Firefox, Chrome and Opera support fonts in TTF and OTF.
Compatibility between source formats:
+----------------------------------------------------+
| Browser | IE8+ | Chrome | Firefox | Safari |
|---------|------------------------------------------|
| Formato | EOT | TTF e OTF | TTF e OTF | TTF e OTF |
+----------------------------------------------------+
For font support in various browsers you can do this:
@font-face {
font-family: ‘NomeDaFont';
src: url(‘nomedafont.eot’); /* EOT para IE */
src: url(‘nomedafont?#iefix’) format(‘embedded-opentype’),
url(‘nomedafont.svg#Locaweb-Icons’) format(‘svg’), /* SVG */
url(‘nomedafont.ttf’) format(‘truetype’); /* TTF para Safari, Firefox, Chrome e Opera */
font-weight: normal;
font-style: normal;
}