If you want an embedded programming, OS, or firmware job, your best bet is with a hardware/semiconductor company. No, you don't need a masters or doctorate -- a CS degree is just fine. I highly recommend taking a low level job; you learn an amazing amount that is abstracted away at the high-level web/database areas.

Have a look at the big hardware vendors: Qualcomm, Broadcom, Freescale (NXP), Nvidia, Cirrus Logic, Xilinx, Apple, Intel, AMD, etc. Note that you'd probably need to be willing to move to a more hardware-oriented area, including California, Silicon Valley, Austin, Boston, or Portland.