1. A method of reducing buried oxide undercut during FinFET formation, comprising:
forming a fin on a buried oxide layer;
forming a source region adjacent a first end of the fin and a drain region adjacent a second end of the fin, the fin, source region and drain region each having an upper surface and a plurality of side surfaces;
forming a sacrificial oxide layer over the upper surfaces and the plurality of side surfaces of the fin and source and drain regions; and
forming a gate over the fin, wherein the sacrificial oxide layer reduces undercutting of the buried oxide layer during gate formation.
2. The method of claim 1, wherein forming the gate over the fin comprises:
forming a dummy gate comprising a first material in a first pattern over the fin;
forming a dielectric layer adjacent sides of the dummy gate;
removing the first material to form a trench in the dielectric layer corresponding to the first pattern; and
forming the gate in the trench.
3. The method of claim 2, wherein the dielectric layer comprises tetraethylorthosilicate.
4. The method of claim 2, further comprising:
forming a gate insulation layer in the trench prior to forming the gate.
5. The method of claim 4, wherein the gate insulation layer comprises at least one of SiO, SiO2, SiN, SiON, HFO2, ZrO2, Al2O3, HFSiO(x) ZnS, or MgF2.
6. The method of claim 2, wherein the first material comprises polysilicon.
7. The method of claim 2, wherein forming the dummy gate comprises:
depositing a layer comprising the first material over the sacrificial oxide layer and the fin; and
etching the layer comprising the first material to form the dummy gate in the first pattern.
8. The method of claim 2, wherein forming the gate comprises:
depositing a metal material to fill the trench.
9. The method of claim 1, wherein the sacrificial oxide layer comprises silicon oxide.
10. The method of claim 9, wherein the sacrificial oxide layer has a thickness ranging from about 100 \u212b to about 500 \u212b.
11. A method of forming a fin field effect transistor, comprising:
forming a fin upon a buried oxide layer;
forming a source region adjacent a first end of the fin and a drain region adjacent a second end of the fin, the fin, source region and drain region each having an upper surface and a plurality of side surfaces;
forming a sacrificial oxide layer over the upper surfaces and the plurality of side surfaces of the fin and source and drain regions;
depositing a layer comprising a first material over the fin and sacrificial oxide layer;
etching the layer comprising the first material to form a dummy gate, wherein the sacrificial oxide layer reduces undercutting of the buried oxide layer during the etching;
depositing a dielectric layer over the dummy gate and source and drain regions;
planarizing the dielectric layer to expose a top surface of the dummy gate;
removing the layer comprising the first material to form a trench in the dielectric layer;
forming a gate insulation layer in the trench; and
forming a final gate in the trench.
12. The method of claim 11, wherein the dielectric layer comprises tetraethylorthosilicate.
13. The method of claim 11, wherein the first material comprises polysilicon.
14. The method of claim 11, wherein the gate insulation layer comprises at least one of SiO, SiO2, SiN, SiON, HFO2, ZrO2, Al2O3, HFSiO(x) ZnS, or MgF2.
15. The method of claim 11, wherein the sacrificial oxide layer comprises silicon oxide.
16. The method of claim 11, wherein the sacrificial oxide layer has a thickness ranging from about 100 \u212b to about 500 \u212b.
17. The method of claim 11, wherein the final gate comprises a metal.
The claims below are in addition to those above.
All refrences to claim(s) which appear below refer to the numbering after this setence.
1. A method of call handling in a wireless communication network comprising:
receiving an incoming voice call for a mobile station that is busy in a packet-switched data call;
sending an incoming call notification to the mobile station via signaling over an existing traffic channel allocated to the data call; and
reconfiguring the existing traffic channel to support the incoming voice call and delivering the incoming voice call to the mobile station via the reconfigured existing traffic channel.
2. The method of claim 1, further comprising suspending or ending a data transaction associated with the data call.
3. The method of claim 1, wherein reconfiguring the existing traffic channel for use delivering the incoming voice call to the mobile station comprises establishing a new service option connection at a network Base Station (BS), and requesting a network Mobile Switching Center (MSC) to establish a voice connection for the incoming voice call.
4. The method of claim 3, further comprising requiring a return indication from the mobile station that indicates call delivery is desired before renegotiating the existing traffic channel.
5. A method of call handling in a wireless communication network comprising:
receiving an incoming voice call indication at a Base Station (BS) that is targeted to a mobile station busy in a packet-switched data call; and
sending a call notification message to the mobile station and, responsive to receiving a return acknowledgment from the mobile station, reconfiguring the service connection of the mobile station to deliver the incoming voice call using the existing traffic channel.
6. The method of claim 5, further comprising releasing a packet data service associated with the packet-switched data call.
7. The method of claim 5, wherein reconfiguring a service connection of the mobile station to deliver the incoming voice call using an existing traffic channel previously allocated to the data call comprises:
sending a voice service call setup request to a Mobile Switching Center (MSC);
receiving a voice circuit assignment from the MSC;
establishing a voice service option connection at the BS to support the incoming voice call; and
alerting the mobile station to inform the mobile station that the incoming voice call is setup.
8. The method of claim 7, wherein sending a voice service call setup request message to a Mobile Switching Center (MSC) comprises generating default voice service parameters at the BS rather than receiving requested voice service parameters from the mobile station.
9. A Base Station (BS) to provide a call handling in a wireless communication network, the BS comprising:
call processing and interface circuits configured to provide voice and data call handling for a plurality of mobile stations; and
a notification processor configured to:
receive an incoming voice call indication at a Base Station (BS) that is targeted to a mobile station busy in a packet-switched data call; and
send a call notification message to the mobile station and, responsive to receiving a return acknowledgment from the mobile station, reconfigure the service connection of the mobile station to deliver the incoming voice call using the existing traffic channel.
10. The BS of claim 9, wherein the BS is configured to suspend a packet data service associated with the data call after connecting the incoming voice call.
11. The BS of claim 9, wherein the BS is configured to release a packet data service associated with the data call after connecting the incoming voice call.
12. The BS of claim 9, wherein the BS reconfigures a service connection of the mobile station to deliver the incoming voice call using an existing traffic channel previously allocated to the data call based on:
sending a voice service call setup request to a Mobile Switching Center (MSC);
receiving a voice circuit assignment from the MSC;
establishing a voice service option connection at the BS to support the incoming voice call; and
alerting the mobile station to inform the mobile station that the incoming voice call is setup.
13. The BS of claim 12, wherein the BS is configured to send the voice service call setup request message to a Mobile Switching Center (MSC) as an additional services request message that includes default voice service parameters generated by the BS rather than by receiving requested voice service parameters from the mobile station.
14. A method of call handling in a mobile station for use in a wireless communication network, the method comprising:
carrying on a packet-switched data call over an existing traffic channel; and
renegotiating the existing traffic channel for circuit-switched voice call use responsive to signaling from the network, said renegotiating including receiving a call notification from the network via signaling on the existing traffic channel indicating that an incoming circuit-switched voice call is pending for the mobile station, returning a notification response to the network via signaling on the existing traffic channel based on prompting a user of the mobile station as to whether receipt of the incoming circuit-switched voice call is desired, sending and receiving signaling as needed to and from the network via the existing traffic channel to reconfigure it for circuit-switched voice use, and receiving an alert message from the network via signaling on the existing traffic channel indicating that the incoming circuit-switched voice call is set up and returning a call connect order to the network via signaling on the existing traffic channel; and
changing from carrying on the packet-switched data call to carrying on the circuit-switched voice call over the existing traffic channel.