How to avoid *.*~ backup files in emacs

Following coding in .emacs can change the default backup folder
(setq backup-directory-alist '(("." . "~/.emacs.d/backup"))
  backup-by-copying t    ; Don't delink hardlinks
  version-control t      ; Use version numbers on backups
  delete-old-versions t  ; Automatically delete excess backups
  kept-new-versions 20   ; how many of the newest versions to keep
  kept-old-versions 5    ; and how many of the old