OnTriggerExit happens when a rigibody instantiate

hello,I got a weird problem. When my character throw an axe ,OnTriggerExit happen and OnTriggerEnter happen soon.I don't know why OnTriggerExit happen and it makes the OnTriggerEnter happen soon when I throw(Instantiate) an axe. here is about the OnTriggerEnter and OnTriggerExit

 var Vikin:GameObject;
 var enemy:GameObject;
 static var firestatue:boolean;
 var sta:boolean;
 var target1:GameObject;
 var target2:GameObject;
 var target3:GameObject;
 var crosshair:GameObject;
 var startfight:AudioClip;
 var fighting:AudioClip;
 var magicPoint:Transform;
 var magic:GameObject;
 function Start () {
 
 }
 
 
 function Update () {
 
 
 }
 
 function OnTriggerEnter(other : Collider)
 {
     if(other.tag=="Viking"&&firestatue==false)
     {
         firestatue=true;
         target1.GetComponent.<Animation>().Play("Target_Up");
         GameObject.Find("Vikin").GetComponent.<AudioSource>().PlayOneShot(startfight);
         Instantiate(magic,magicPoint.position,magicPoint.rotation);
         yield WaitForSeconds(1);
         Debug.Log(other.gameObject.name);
     
     Debug.Log(firestatue);
     }
 } 

 function OnTriggerExit(other : Collider)
 {
     
     if(other.tag=="Viking"&&firestatue==true)
     {
         firestatue=false;
         target1.GetComponent.<Animation>().Play("Target_Down");
         GameObject.Find("Vikin").GetComponent.<AudioSource>().Stop();
         Debug.Log("TriggerExit");
          
     }
 }

and here is about the Instantiate of the axe

 #pragma strict
 var axeRigi:Rigidbody;
 var yThrower:float;
 var zThrower:float;
 var throwAudio:AudioClip;
   
 function Start () {
 
 }
 
 function Update () {
 if(Input.GetButtonDown("Fire1"))
 {
 var axe1=Instantiate(axeRigi,transform.position,transform.rotation);
 axe1.GetComponent.<Rigidbody>().velocity=transform.TransformDirection(Vector3(0,yThrower,zThrower));
 Physics.IgnoreCollision(axe1.GetComponent.<Collider>(),transform.root.GetComponent.<Collider>());
 GetComponent.<AudioSource>().PlayOneShot(throwAudio);
 }
 
 }

the tag "Viking" is on my character ,of course the axe's tag is "tag_axe" not "Viking" plz somebody help me it's confused me so much