I had a similar problem with our Kia. I put new pads and rotors on and it developed a vibration when applying the brakes. I found out I had bad wheel bearings on both sides. Replaced both wheel bearings, problem solved. Could also be a bad rotor too.
Steve & Cheryl w/3rd Crewmember Peanut, Our Deerhead Chiuaua
2000 Winnebago Adventurer 35U F53, V10 Gasser,Safe T Plus
2004 Wrangler Toad via Stowmaster 5000, BrakeBuddy Classic
Marriage is a relationship in which one is always right and the other is the husband