Button not clickable after InAppBrowser

I have a problem with the Cordova InAppBrowser plugin. I want to load the InAppBrowser right after the Ionic.Platform.ready event. This works fine and right after the splash-screen the InAppBrowser gets loaded. Now, if I close the InAppBrowser I can not click on my button with ng-click to open a new InAppBrowser.
My button looks like this:
<button type="button" class="..." ng-click="open()">Launch</button>
In my controller I have:

$scope.open = function () {

	var ref = cordova.InAppBrowser.open('https://someadress', '_blank', 'location=no');



If I remove the $scope.open(), the button works as it is supposed to.
Thanks in advance!