None of the Microsoft Office programs have a default shortcut to open them directly. However, you can add any key combination to open the applications if you right-click on the launcher and select Properties. After that, select the Shortcut tab, click the None entry next to Shortcut key and press a key from your keyboard. If you will press a letter or a number, Windows will add Alt + Ctrl, but if you press something like F1, F2 and so on, Windows will not add anything and you will be able to open the document using a single key.
