Search Help MAT1

Hi ABAP Guru's -

My requirement goes like: I have a Zfield pointing to dataelement MATNR in a screen.. When the user hits F4 I want to bring up the search help for MATNR but take him directly to "Material by material type" tab and default the "Material Type" value.. How can I do this??

Nice to have function is to eliminate all the other tabs and show just "Material by material type"..

Please help ASAP..

Regards

Sudhakar