how do I create a freeze blast

I want a script that will freeze enemies for a few seconds. I have a shooting script, but I don't know how I would freeze the enemies.

This is My shooting script

     var projectile : Rigidbody;
     
      function Update () {
     
         if (Input.GetKeyDown(KeyCode.Mouse0)) {
     
            var clone : Rigidbody;
     
            clone = Instantiate(projectile, transform.position, transform.rotation);
     
            clone.velocity = transform.TransformDirection (Vector3.forward * 50);
         
         }
  }