Touch-File.ps1

Function Touch-File
{
param(
    [Parameter(Mandatory=$True)]
    $Path
)
    if(Test-Path $Path)
    {
        Set-ItemProperty -Path $Path -Name LastWriteTime -Value $(get-date) -PassThru | Get-Item
    }
    else
    {
        New-Item -Path $Path -ItemType File
    }
}