No. The maximum bid that you have chosen for your ad is the maximum amount of money that you are willing to pay for each click. However, each click always costs less than that. Increasing your maximum bid, your ad will occupy a wider range of the network.
A 960*144 image is enough to create your desired Ad, but it is recommended to prepare three images in three different sizes (960*144, 640*96, 480*72 pixels; they should be limited to 40 KB,70 KB and 150 KB.); larger images will be shown in tablets and larger devices and can include more details, and smaller images are shown in smaller devices and might include less details.