Succulents do well when they're planted in pots with at least 2 inches in depth.
You can go a little deeper than 2 inches but the minimum for the succulents to be planted and thrive is 2 inches deep.
It's best to fill the bottom of the pot with some gravel and then add the top soil and plant the succulents then.
The pot should also have drainage holes to allow the excess water to drain out and the gravel will also help promote drainage of the excess water.