how can i create an object that perfectly fits any screen size based on resolution

i want to create an object that takes screen.width and screen.height, converts them to unitys units and feeds it to the transform.localScale.
i can’t simply create a huge object, that fills every screen, because its size must match the screen.
any idea on how i could make this work? is there a better way to do this?

i found a solution. (maybe there’s a better one, let me know if you know one)
i scaled the object to match screenSize in units, and scaled the orthographic CameraSize 5 * screen.height.

transform.localScale = new Vector3 (Screen.width, 0, Screen.height);

MainCamera.GetComponent ().orthographicSize = (Screen.height * 5);