You're Correct!

If you are looking to get your golf pitch shots to check on the green more, then you need to strike down on the ball more with the club head.

Getting the club head to strike down on the ball will generate more spin and when the ball spins more, it will check and stop quicker on the green.

To set up correctly to hit an effective pitch shot, initially place the ball in the centre of your stance as this will allow you to make a downward striking action with the club head through impact. Place your feet slightly closer together than usual and ensure that you put your left foot directly back by about four inches, so that your left toes are in line with the end of your right shoelaces.
The key to ensuring that you get a downward strike through impact is to now set up with your hands forward. This simply means that your hands and the handle of the club are closer to the target than the club head is.

To achieve this, create a straight line from your left shoulder down your left arm and then directly down the shaft of the golf club, if you are a right-handed golfer. The shaft of the golf club should be leaning forwards towards the target. You also want to make sure that you set your head just to the left of the golf ball, so position your nose just to the left of the ball. This will now mean that you have more weight on your left side at set up and the consequence of this is that you will swing the club back slightly steeper than usual, giving you a steeper downward angle of attack towards the ball. This steeper angle of attack will allow you to strike downwards with the club head through impact, allowing you to strike the ball and then the turf. Striking the ball and then the turf in this way will then force the ball up the club face making it spin, so that when it lands on the ground it checks and stops very quickly.

Here is a really good drill to ensure you get a downward strike through impact with the club head. Place a head cover from one of your woods on the target line about two feet to the right of the golf ball. This should place it just to the right of your right foot. Without involving the ball initially, swing the club back over the head cover so that you do not disturb it and on your down swing work on striking the ground to the left of the head cover again without hitting it. Do this slowly initially getting a feel for the movement and then once youre achieving this and becoming more confident, start to swing the club slightly faster. Once you can swing the club and strike the ground on the left of the head cover without hitting it at a more realistic swing speed, then reintroduce the golf ball and work on this drill actually striking the ball.

If you are striking the ball part way up, or striking the top of the golf ball, then the ball will not be forced up the club face. The ball will be hit very low and it will roll across the green and not check on it at all. To create check you need to strike down so that the ball is forced up the club face, which generates spin and check on the green.

Striking the ground before the golf ball, will produce a short and low golf shot. The ball will roll along the ground with no check on it because the turf has moved and pushed it forwards, not the club head. Striking the turf into the ball will not generate any spin that will cause the ball to check.

If you swing the club head back on too steep a swing plane, you will swing the club head back down towards the golf ball from too vertical a position and as a consequence you will strike the top of the golf ball. A topped golf shot rolls very low and keeps rolling, so no check will be seen on the green with this shot.