Simulate Latch : Cache Buffer Chains

I want to simulate latch : cache buffer chains wait event due to use of nested loop join for lookup tables

This is what a tried :

-- create parent / child tables

SQL>drop table emp1 purge;
drop table dept1 purge;
create table dept1 (dept_id number primary key,
dept_name char(30));

[Code]....

I traced many queries like the one given below (dept_id between 1 and n where n varied from 10 to 1000) but they always result in hash join

1* select d.dept_name, e.id from sys.dept1 d, sys.emp1 e where d.dept_id = e.dept_id and e.dept_id < 1000

Execution Plan
----------------------------------------------------------
Plan hash value: 619452140

----------------------------------------------------------------------------
| Id | Operation | Name | Rows | Bytes | Cost (%CPU)| Time |
----------------------------------------------------------------------------
| 0 | SELECT STATEMENT | | 998K| 41M| 680 (2)| 00:00:09 |
|* 1 | HASH JOIN | | 998K| 41M| 680 (2)| 00:00:09 |
|* 2 | TABLE ACCESS FULL| DEPT1 | 999 | 34965 | 4 (0)| 00:00:01 |
|* 3 | TABLE ACCESS FULL| EMP1 | 999K| 8780K| 672 (2)| 00:00:09 |
----------------------------------------------------------------------------

what can I do to get a nested loop join to simulate latch : cache buffer chains?