Can we take one slab of p-type semiconductor and physically join it to another n-type semiconductor to get p-n junction?

Why can't we take one slab of p-type semiconductor and physically join it to another slab of n-type semiconductor to get a p-njunction?

p-type and n-type semiconductors .

Semiconductor || P-N junction

Why can't we physically join p-type and p-type semiconductor directly to form a p-n junction ?

bond in n and p type semiconductor is

Bond in n and p-type semiconductor is

What are n-type and p-type semiconductors?