phaser3 How to use a simple timer from 0 to 3

[Ced]

Hello! I am using the following code (which is a simplified snippet in order to make it more readable):

which is a simplified snippet in order to make it more readable

var player;
var box_tnt;

function create (){
    this.physics.add.collider(player, box_tnt, hitTnt, null, this);
}

//the function hitTnt stop the game because the player died
function hitTnt (player, boxes){
    this.physics.pause();
    player.setTint(0xff0000);
    player.anims.play('default');
    gameOver = true;
    textGameOver.setText('GAME OVER');
}

Actual comportment: when the player hit the bomb: player die; end of the game
Desired comportment: when the player hit the bomb: the bomb wait 3 secondes and then explode ! If the player is too close he die.
But I stuggle a lot to use a timer even after reading a lot of example in the forum I am a newbie concerning Phaser so I didn't succeed to it so far.

Any help would be appreciated, thank you in advance!